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The chemistry of cosmetics |
Posted by: fw115ww - 09-03-2021, 03:18 AM - Forum: Welcomes and Introductions
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Cosmetics materials are not a modern invention. Humans have used various substances to alter their appearance or accentuate their features for at least 10,000 years, and possibly a lot longer.
Women in Ancient Egypt used kohl, a substance containing powdered galena (lead sulphide—PbS) to darken their eyelids, and Cleopatra is said to have bathed in milk to whiten and soften her skin. By 3000 B.C men and women in China had begun to stain their fingernails with colours according to their social class, while Greek women used poisonous lead carbonate (PbCO3) to achieve a pale complexion. Clays were ground into pastes for cosmetic use in traditional African societies and indigenous Australians still use a wide range of crushed rocks and minerals to create body paint for ceremonies and initiations.
Today, cosmetics are big business. According to the 2011 Household Expenditure Survey, conducted every five years by the Australian Bureau of Statistics, Australians spend around $4.5 billion on toiletries and cosmetic products every year. Cosmetic advertising, previously directed mainly at women, is now targeting a wider audience than ever.
What is a cosmetic?
In Australia, a cosmetic is defined under the Industrial Chemical (Notification and Assessment) Act 1989 as ‘a substance or preparation intended for placement in contact with any external part of the human body' (this includes the mouth and teeth). We use cosmetics to cleanse, perfume, protect and change the appearance of our bodies or to alter its odours. In contrast, products that claim to ‘modify a bodily process or prevent, diagnose, cure or alleviate any disease, ailment or defect’ are called therapeutics. This distinction means that shampoos and deodorants are placed in the cosmetics category, whilst anti-dandruff shampoos and antiperspirants are considered to be therapeutics.
Regulation and safety
In Australia, the importation, manufacture and use of chemicals—including those used in cosmetics—are regulated by the Australian Government’s National Industrial Chemicals Notification and Assessment Scheme (NICNAS). NICNAS works to ensure that chemicals used in consumer products do not cause significant harm to users or to the environment.
In the case of cosmetics, every ingredient contained within the product must be scientifically assessed and approved by NICNAS before being manufactured or imported into Australia and before they can be used in consumer products. Where appropriate, NICNAS sets limits on the level at which a chemical can be used in a product and also conducts reviews on chemicals when new evidence arises.
Cosmetic products that make an additional therapeutic claim (such as moisturisers that also lighten the skin) are regulated by a different organisation—the Therapeutic Goods Administration (TGA).
Cosmetics and other personal care items must also be labelled in accordance with the Trade Practices (Consumer Product Information Standards, Cosmetics) Regulations 1991. This regulation requires that all intentionally added ingredients are listed on the product label, and is enforced by the Australian Competition and Consumer Commission (ACCC).
What do cosmetics contain?
There are thousands of different cosmetic products on the market, all with differing combinations of ingredients. In the United States alone there are approximately 12,500 unique chemical ingredients approved for use in the manufacture of personal care products.
A typical product will contain anything from 15–50 ingredients. Considering the average woman uses between 9 and 15 personal care products per day, researchers have estimated that, when combined with the addition of perfumes, women place around 515 individual chemicals on their skin each day through cosmetic use.
But what exactly are we putting on our skin? What do those long names on the ingredient list mean and what do they do? While the formula of each product differs slightly, most cosmetics contain a combination of at least some of the following core ingredients: water, emulsifier, preservative, thickener, emollient, colour, flavors and fragrances and pH stabilisers.
Water
If your product comes in a bottle, chances are the first ingredient on the list is going to be water. That’s right, good old H2O. Water forms the basis of almost every type of cosmetic product, including creams, lotions, makeup, deodorants, shampoos and conditioners. Water plays an important part in the process, often acting as a solvent to dissolve other ingredients and forming emulsions for consistency.
Water used in the formulation of cosmetic materials is not your everyday, regular tap water. It must be ‘ultra-pure’—that is, free from microbes, toxins and other pollutants. For this reason your label may refer to it as distilled water, purified water or just aqua.
Emulsifiers
The term emulsifiers refers to any ingredient that helps to keep unlike substances (such as oil and water) from separating. Many cosmetic products are based on emulsions—small droplets of oil dispersed in water or small droplets of water dispersed in oil. Since oil and water don't mix no matter how much you shake, blend or stir, emulsifiers are added to change the surface tension with surfactant materials between the water and the oil, producing a homogeneous and well-mixed product with an even texture. Examples of emulsifiers used in cosmetics include polysorbates, laureth-4, and potassium cetyl sulfate.
Preservatives
Preservatives are important ingredients. They are added to cosmetics to extend their shelf life and prevent the growth of microorganisms such as bacteria and fungi, which can spoil the product and possibly harm the user. Since most microbes live in water, the preservatives used need to be water-soluble, and this helps to determine which ones are used. Preservatives used in cosmetics can be natural or synthetic (man-made), and perform differently depending on the formulation of the product. Some will require low levels of around 0.01%, while other will require levels as high as 5%.
Some of the more popular preservatives include parabens, benzyl alcohol, salicylic kojic acid, formaldehyde and tetrasodium EDTA (ethylenediaminetetra-acetic acid).
Consumers who purchase ‘preservative-free’ products should be aware of their shorter shelf life and be conscious of any changes to the look, feel or odour of the product that may indicate it has gone off.
Thickeners
Thickening agents work to give products an appealing consistency. They can come from four different chemical families:
Lipid thickeners are usually solid at room temperature but can be liquefied and added to cosmetic emulsions. They work by imparting their natural thickness to the formula. Examples include cetyl alcohol, stearic acid and carnauba wax.
Naturally derived thickeners come, as the name suggests, from nature. They are polymers that absorb water, causing them to swell up and increase the viscosity of a product. Examples include hydroxyethyl cellulose, guar gum, xanthan gum and gelatin. Cosmetics with a consistency that is too thick can be diluted with solvents such as water or alcohol.
Mineral thickeners are also natural, and as with the naturally derived thickeners mentioned above, they absorb water and oils to increase viscosity, but give a different result to the final emulsion than the gums. Popular mineral thickeners include magnesium aluminium silicate, silica and bentonite.
The final group are the synthetic thickeners. They are often used in lotion and cream products. The most common synthetic thickener is carbomer, an acrylic acid polymer that is water-swellable and can be used to form clear gels. Other examples include cetyl palmitate, and ammonium acryloyldimethyltaurate.
Emollient
Emollients soften the skin by preventing water loss. They are used in a wide range of lipsticks, lotions and cosmetics. A number of different natural and synthetic chemicals work as emollients, including beeswax, olive oil, coconut oil and lanolin, as well as petrolatum (petroleum jelly), mineral oil, almond oil, glycerine, zinc oxide, butyl stearate and diglycol laurate.
Colouring agents/pigments
Ruby lips, smoky eyes and rosy cheeks; it is the purpose of many cosmetics to accentuate or alter a person’s natural colouring. A huge range of substances are used to provide the rainbow of appealing colours you find in the makeup stand. Mineral ingredients can include iron oxide, mica flakes, manganese, chromium oxide and coal tar. Natural colours can come from plants, such as beet powder, or from animals, like the cochineal insect. The latter is often used in red lipsticks and referred to on your ingredient list as carmine, cochineal extract or natural red 4.
Pigments can be split into two main categories: organic, which are carbon-based molecules (i.e. organic in the chemistry context, not to be confused with the use of the word to promote ‘natural’ or ‘non-synthetic’ or ‘chemical-free’ products) and inorganic which are generally metal oxides (metal + oxygen and often some other elements too). Inorganic should not be confused with ‘synthetic’ or ‘unnatural’ as most of the inorganic metal oxide pigments do occur naturally as mineral compounds.
The two most common organic pigments are lakes and toners. The lake pigments are made by combining a dye colour with an insoluble substance like alumina hydrate. This causes the dye to become insoluble in water, making it suitable for cosmetics where water-resistant or waterproof properties are desired.
A toner pigment is an organic pigment that has not been combined with any other substance.
The inorganic metal oxide pigments are usually duller than the organic intermediate pigments, but are more resistant to heat and light, providing a longer-lasting colour.
Glimmer and shine
Shimmering effects can be created via a range of materials. Some of the most common ones are mica and bismuth oxychloride.
Cosmetic mica typically comes from muscovite (KAl2(AlSi3O10)(F,OH)2) also known as white mica. It naturally forms in flaky sheets and these are crushed up into fine powders. The tiny particles in the powders refract (bend) light, which creates the shimmering effect common in many cosmetics. Mica coated with titanium dioxide gives a whitish appearance when looked at straight on, but then produces a range of iridescent colours when viewed from an angle.
Bismuth oxychloride (BiClO) is used to create a silver grey pearly effect. This compound occurs naturally in the rare mineral bismoclite, but is usually produced synthetically and so is also known as synthetic pearl.
The size of the particles used to create pearly and shimmering looks affect the degree of glimmer the product has. The smaller the particle size (15–60 microns, where one micron is one millionth of a meter), the less lustrous the powder will be, and more coverage it gives. Larger particle sizes, up to 500 microns, give a more glittery lustre and are more transparent.
Fragrances
No matter how effective a cosmetic may be, no one will want to use it if it smells unpleasant. Consumer research indicates that smell is one of the key factors in a consumer’s decision to purchase and/or use a product.
Chemicals, both natural and synthetic, are added to cosmetics to provide an appealing fragrance. Even ‘unscented’ products may contain masking fragrances to mask the smell of other chemicals.
The term ‘fragrance’ is often a generic term used by manufacturers. A single listing of fragrance on your product’s ingredient list could represent dozens or even hundreds of unlisted chemical compounds which were used to create the final individual fragrance.
Manufacturers do not have to list these individual ingredients as fragrance is considered to be a trade secret.
There are over 3,000 chemicals used to formulate the huge range of fragrances used in consumer products worldwide. A comprehensive list has been published by the fragrance industry. All the ingredients on this list have passed the International Fragrance Association (IFRA) safety standards for use in commercial products. However, without knowing which individual ingredients went in to making up the fragrance of a product, consumers can find it difficult to make informed choices. If consumers are concerned they should look for fragrance free products and buy from companies that label their products more comprehensively.
Are cosmetics dangerous?
There’s nothing like a bit of controversy to generate some media buzz. For over a decade there have been recurring reports in both the media and on hundreds of internet sites relating to potentially toxic substances present in cosmetics (lead, mercury, parabens) and the dangers they pose to the public. Should consumers be worried? Are these claims backed up by reputable, published scientific research or have the findings been misinterpreted and exaggerated? Let’s take a look …
Parabens
Parabens are a class of chemicals commonly used as preservatives in food, therapeutic and cosmetic products. They are derived from para-hydroxybenzoic acid (PHBA), which occurs naturally in many fruits and vegetables. Parabens come in several forms: methylparaben, ethylparaben, propylparaben, butylparaben and isobutylparaben. They are the most widely used preservative in personal care products. This is because they are incredibly good at doing their job—keeping your products mould and bacteria free—and are also cost effective.
The use of parabens in cosmetics hit the media in 2004 after a research study conducted by Dr. Philippa Darbre of the University of Reading in England reported findings that 18 out of 20 breast cancer tissue samples contained parabens. As parabens can weakly mimic the actions of oestrogen, and as oestrogen can enhance tumour growth, this was thought to be a problem. The presence of parabens in breast tumours was picked up by the media and presented as evidence that parabens contribute to breast cancer. This was incorrect.
While the presence of parabens is notable, the study found no direct evidence that they had caused the cancer or contributed to its growth. Breast tumours have a large blood supply, so it is likely that any chemical found in the blood stream will be present in the tumour.
In a later statement to the media, Dr. Darbre, referring to her 2004 study, said ‘No claim was made that the presence of parabens has caused the breast cancers.’
There have since been dozens of studies undertaken around the globe on the safety of parabens, which time and again have exhaustively demonstrated that parabens are broken down, metabolised and excreted harmlessly from the body.
Currently, both in Australia and internationally, the science community consider the use of parabens in cosmetics to be safe.
In response to consumer demand, some companies have begun to manufacture paraben free products, which consumers can purchase if they are concerned.
Aluminium
Concerns regarding cancer are also linked to the use of aluminium in deodorants and anti-perspirants. In the early 2000s various news outlets reported apparent links between the use of antiperspirants containing aluminium and breast cancer. Similar reports connected the use of such products to the onset of Alzheimer’s disease. These supposed links have never been scientifically proven despite multiple studies.
Aluminium works to block the sweat ducts to reduce sweating. Some argue that this process prevents us from releasing toxins, causing them to build up within our lymph glands. However, breast cancer tumours do not originate in the lymph nodes, they start in the breast, and travel to the lymph nodes later. Another study found no difference in the concentration of aluminium between the cancer and the surrounding tissue.
Currently there is no clear link between the use of under-arm products containing aluminium and breast cancer.
Likewise, studies have shown no relationship between Alzheimer’s disease and deodorant/antiperspirant use. Every day, humans are exposed to aluminium through food, packaging, pots and pans, medicine and even air and water. The official position of both the Alzheimer’s Society (US) and Alzheimer’s Australia is that a link between environmental aluminium absorption and Alzheimer’s disease seems ‘increasingly unlikely’.
Despite these findings, some manufacturers have begun producing aluminium-free products for consumers who still hold concerns.
Triclosan
Triclosan was originally developed as an anti-bacterial agent for use in hospitals, primarily as a surgical scrub. However its usefulness has seen it increasingly added to a wide range of consumer products including deodorant, soap, toothpaste, cosmetics and general house-hold cleaning products. Triclosan is also used as a pesticide and can, under certain circumstances, break down into potentially toxic chemicals such as dioxins.
Triclosan hit the news in 2000 after findings published by the National Academy of Sciences (US) noted rising levels of the chemical being detected in the environment and its increasingly broad use in everyday products as concerns.
Studies conducted by scientists at the University of California found that prolonged exposure to triclosan causes liver fibrosis and cancer in laboratory mice. Other studies have suggested triclosan can disrupt hormones, impair muscle contraction and reduce bacterial resistance.
Whilst the over-use of triclosan in products warrants further study, Australian experts have highlighted its value and importance when used correctly and in moderation. Professor of Dental Science at the University of Queensland, Dr. Laurie Walsh, noted that the chemical has been proven to fight various conditions such as gingivitis, inflammation and bleeding gums.
In Australia, a full risk assessment conducted by NICNAS found no cause for public concern in general, though did recommend controls for maximum concentrations of triclosan (0.3%) in personal care and cosmetic products. At present, cosmetic products containing more than 0.3% triclosan must clearly carry the word ‘poison’ on the label—not the best marketing strategy for producers.
The American Food and Drug Administration (FDA) is planning to release an updated report on Triclosan in 2016, though in the interim consumers may look for triclosan-free products if they wish.
Formaldehyde
Formaldehyde is an organic compound with a wide variety of uses. Although commonly associated with embalming, it is also used in the manufacture of building materials, textiles, household cleaning products, plastics, cosmetics and personal care products. It also occurs naturally in a wide range of foods, for example the humble egg.
Formaldehyde is not typically used in its pure form, but altered slightly and listed under the name formalin. It works as a preservative to protect products from contamination.
Formaldehyde is classified as a Group 1 carcinogen (known to cause cancer in humans) by the World Health Organization International Agency for Research on Cancer. It can also cause skin and sensory irritation and breathing difficulties in people when inhaled, ingested or if it comes into contact with skin. So why is it still used in everyday products?
As with other chemicals, it is the concentration present in a product that is important. NICNAS has assessed formaldehyde and set maximum safe limits for its use in cosmetics. Oral products such as toothpastes may only contain up to 0.1 percent formaldehyde, while nail hardeners can have up to 5 percent. All other cosmetic products (such as shampoos and straightening solutions) can have up to 0.2 percent. At these low levels, the use of formaldehyde is deemed to be safe.
NICNAS has noted that people with particularly sensitive skin may still experience irritation even at these low concentrations.
In 2010, the Australian Competition and Consumer Commission (ACCC) conducted a survey of the formaldehyde concentrations of several cosmetic products that resulted in the voluntary recall of two products that contained unacceptably high concentrations of the chemical.
Phthalates
Phthalates (pronounced THAL-ates) are another group of chemicals found in some cosmetics that have been red-flagged by environmental groups. They are generally used to make plastic products soft and flexible but can also be found in cosmetics like nail polish, hair spray (to make the products less brittle or stiff) and perfumes.
Phthalates are produced from oil and there are more than 20 types in common use. As the various phthalates have different chemical structures, toxicity profiles and uses, their safety should not be generalised as a group, but looked at on an individual basis. Some studies have indicated that at high, recurring concentrations different phthalates can act as endocrine disruptors—this means they upset the hormonal balance in the body and can lead to developmental problems, particularly in males. Other studies have indicated there may be a link between phthalates and type 2 diabetes.
In response, the European Union and the United States have imposed bans on some types of phthalates for use in cosmetics. Research conducted in Australia has identified a small level of risk in relation to one phthalate, bis(2-ethylhexyl) phthalate or DEHP, and as a result NICNAS has prohibited products that contain DEHP above the prescribed level—this generally relates to children’s toys.
Lead in your lipstick?
News reports detailing levels of lead and other metals in lipsticks are persistent and recurring, but should consumers be worried? A 2013 study by the University of California Berkley examined the metal content of 32 different lipsticks. Researchers found traces of aluminium, manganese (which can cause neurological problems) and titanium in all the products they tested, while three-quarters of the products contained lead (which affects the nervous system, and can cause learning disabilities in children). Many of the lipsticks and lip glosses also contained nickel and cobalt, as well as cadmium and chromium—both known carcinogens.
Why would manufacturers add these ingredients to their products? The answer is—they don’t. They exist in the products as ‘impurities’, that is, they are present in other ingredients such as the wax, oils or the mineral pigments used in the formula. Because of the persistent nature of these substances and the fact they occur in the natural environment, including in water, it is almost impossible to remove all traces of them.
However don’t throw your lippy away just yet. The presence of these naturally-occurring elements in lipsticks is not necessarily a problem—the important issue is the level or concentration. Are the the levels high enough to be considered toxic, or are they low enough to be deemed safe? Remember, sunlight is also a proven carcinogen (skin cancer)—but you still go outside and you might even sunbathe. It all comes down to dose.
With the exception of chromium, the study concluded that the metal concentrations were comfortably within the ‘acceptable daily allowances’ as determined by the researchers via a comparison with accepted water and air contamination levels. Basically, you will consume more lead from drinking water than you will from applying lipstick. However, the study did conclude that further research into the metal content of cosmetic products is necessary, particularly with respect to chromium.
Sun creams
While sun creams are not officially cosmetics (they are considered to be therapeutics), we will include them here as their use is so common, particularly in Australia.
Sunscreens play an important role in protecting our skin from the harmful UVA and UVB rays emitted by the sun. Their use has been proven to help prevent certain skin cancers including melanomas and basal cell carcinomas.
In recent years there has been some concern about nanoparticles (NP) in sunscreens. This relates particularly to zinc oxide (ZnO) and titanium dioxide (TiO₂) nanoparticles and their ability to penetrate the skin to reach cells and the potential toxicity exerted by these chemicals.
The position of the Therapeutic Goods Administration (TGA), based on several published papers (up to May 2013) as well as reviews of international authorities, is that nano-particles are safe. ‘Several in vitro and in vivo studies using both animal and human skin have shown that these NPs do not penetrate the underlying layers of skin, with penetration limited to the stratum corneum. This suggests that systemic absorption is unlikely.’
A further study published in 2014 found that when exposed to zinc oxide nanoparticles, human immune cells (called macrophages) effectively absorbed the nanoparticles and broke them down.
Based on current evidence, neither TiO2 nor ZnO nanoparticles are likely to cause harm when used as ingredients in sunscreens. There are more risks associated with avoiding suncreams (sunburn, skin cancers) than there are posed by nanoparticles.
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Here's the Truth About Wood Veneers |
Posted by: fw115ww - 09-03-2021, 03:16 AM - Forum: Welcomes and Introductions
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When you learn that a piece of furniture has a veneer, does it make you cringe a little? Admittedly us, too. But wood veneers, in fact, are a traditional and structurally significant aspect of furniture-making that still come into play in contemporary design. Wood veneers have been used in furniture-making and millwork techniques for over 200 years, says interior designer Cate Caruso, of Studio C, who uses them for all kinds of high-quality custom furnishings. In woodworking, a veneer is actually a paper thin cut of wood that's applied to both sides of a strong core surface, like furniture-grade MDF or substrate material, to seal and stabilize it—which is critically important when you're fashioning built-in furniture or anything with a mechanism. The reason is simple: Solid wood expands and contracts as the temperature changes, and your apartment isn't temperature controlled no matter how powerful your A.C. unit is. A dining table, for instance, can be made from solid wood (and many are), but a wood piece with moving parts cannot. With kitchen cabinetry, drawers, and anything built-in or paneled, you really have to have veneers, Caruso explains. A solid piece of wood just isn’t always structurally sound enough to fabricate a millwork.
What she is not using is fake wood. Oftentimes, when people see a veneered furnishing that’s cheap, it’s actually not wood at all—it’s a laminate material, Caruso explains, putting a name to the faux surface that gave all veneers a bad rap somewhere along the line. (Those are made from plastic, paper, or even foil that's been printed with a wood grain pattern that often wears away at the edges—a sure way to spot them.) But of course, there's also a range in quality of proper veneers depending on who makes them. All woodworking can be done well or it can be done poorly—but an expert millworker will make veneers look seamless, with perfect corners, Caruso says, which explains the misconception that a wood engineered veneer is cheap when it’s anything but.
Besides keeping a wood panel stable, veneers have other perks and purposes. They're considered an environmentally conscious option because you're maximizing that log in thin little sheets, Caruso says, and then the core is furniture grade MDF or substrate material. In extreme cases, they can even be cost-saving. Think about Brazilian rosewood, which is rare, endangered, very hard to get, and very expensive, says Patrick Muecke, Caruso's general contractor, who was a millworker for 15+ years before opening his own GC and management company. If you want to do a rosewood paneled room in solid wood, you’d have to be the Sultan of Brunei in order to afford it. The same would go for any project in an expensive wood; veneers would bring down the cost. Beyond millwork, natural bamboo veneers are also required for certain special techniques: Book-matched wood doors (or book-matched wood anything) would have to be fashioned using bamboo veneers because you'd never find wood planks with grains that perfectly match—it's necessary instead to have a series of veneers cut from the same log. Then there are labor-intensive inlay arts like marquetry and parquetry, which require veneers cut to certain sizes and shapes that are then fit into the top of a structure. A far cry from laminate surfaces, right?
When you’re choosing your residence hall furniture and deciding on the specs, you’ll inevitably choose what materials you want.
Should it be totally solid wood or a laminate variety?
If you choose to go with the latter, you’ll have to answer another important question.
What kind of wood edge banding do you want?
For many people who are new to buying residence hall furniture, that’s going to elicit some questioning faces.
What’s edge banding? Good question.
Or, if you’re a veteran, you already know how painful the wrong edge banding choice can be. That is to say, peeling, ongoing maintenance, and mounting work orders.
What Is Edge Banding?
So let’s start at the beginning. What is edge banding?
It’s actually kind of simple, and the video below will help you understand it even better, but this is a simple overview to get you started.
Here’s the basic non-technical idea.
Plywood, particle board, and other manufactured wood cores like MDF have rough, unfinished, unprotected, and generally unsightly edges.
To account for that, some clever folks developed technologies that allow you to glue different bands of glossy finished material to those rough edges to match the tops and sides.
Those narrow bands or strips are called edging tape, and they range in thickness from 0.018-inch to 5mm thick and in 250 ft rolls.
The thicker edging is used in high traffic and commercial environments because it provides greater resilience and impact resistance. For example, the military requires a thicker ⅜” solid wood edge banding for maximum impact resistance.
And edge banders are the industrial grade machines that apply the edging tape to the raw edges of the wood panels with a hot-melt adhesive or glue.
The Purpose of Edge Banding
Edge banding serves both functional and aesthetic purposes.
Functionally, edge bands perform some key duties for your furniture. First, it keeps moisture out serving as a de facto seal on the edge of the core material. Second, edge banding improves durability and resilience by providing impact resistance. If you’re using solid wood edging, it can also add to the overall strength of the furniture.
Aesthetically, edge banding covers up unsightly rough edges and creates a glossy finish to match your tops and sides. You can also create radial edges to soften sharp angles.
What Is Edge Banding Made From?
What are the edging tapes made from? There are different materials, and we’ll just focus on a few here.
1. PVC is the most popular material for edge banding. Pros: It’s inexpensive, durable, and boasts a long life. It doesn’t require any finishing process. It’s also easy, albeit tedious, to repair. Cons: You can’t recycle it. It doesn’t biodegrade. Once it’s blemished, you can’t refinish it. (NB: ABS—Acrylonitrile Butadiene Styrene—is an eco friendly alternative to PVC because it’s both recyclable and safe to incinerate.)
When it comes to PVC, we recommend 3mm edging in general because it goes on cleaner, quicker, and with better adhesion. Another advantage is that you get a graceful radius and a nice soft-looking finish. In general, we avoid .5mm edging because the corners tend to be too sharp.
2. Solid Wood is still a favorite in many woodworking camps. It’s durable, recyclable, easy to fix and refinish, strong, stiff, and economical. Benefits: is more resistant to chipping than veneer edge tape. Solid wood glues are more reliable and less prone to peeling than veneer and PVC. It provides additional dimensional support to plywood and mdf. Climate neutral manufacturing. Cons: Difficult to use for curves.
When it comes to solid wood we recommend 9.5mm on case good tops.
As we explain below, at DCI, we believe the best way to apply wood edge banding is “internally” with a HPL top. Why? Because in our experience, it’s incredibly durable and never requires additional service.
Wood Veneer
3. Wood Veneer, including reconstituted veneer is another common edge banding material. It’s made from thin slices of wood—typically oak, maple, ash, walnut, birch, and mahogany—that are joined together in a roll using finger jointing. It usually features a heat-sensitive glue backing.
Pros: It’s attractive, durable, and strong. It provides a clean solid-wood look, and it’s pre-sanded to easily absorb stains and finishes to seamlessly match your wood. Cons: It’s not heat resistant. Avoid putting it near a heater. It doesn’t do well in high-use environments.
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UNDERSTANDING AUDIO AND VIDEO WIRE AND CABLE |
Posted by: fw115ww - 09-03-2021, 03:14 AM - Forum: Welcomes and Introductions
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WHAT IS A CONDUCTOR?
An Electrical conductor is an element (remember the periodic table in chemistry?) which conducts electricity, as opposed to an insulator, which does not, or a semiconductor which allows some electricity to pass. There are also alloys that have different electrical characteristics, and platings or other element to element contacts such as in connectors which also have electrical characteristics as well as chemical characteristics in their applications. Simply stated - it is not just a matter of connect metal to metal and you have a good connection. The best connectivity designs take into account the source connector materials, the receiving device connector materials, the audio video wire connector materials, the conductor materials and the electrical and chemical ways in which they interact with one another.
MEET THE CONDUCTORS - SILVER, COPPER, GOLD, TIN, NICKEL, STEEL
1. Silver is the best conductor, with a very slight edge over copper. Silver also has the benefit of having oxidation that conducts as well as unoxidized silver.
2. Copper is the next best conductor, with about 1.05 times the resistance of silver, and due to its lower cost is the most commonly used conductor for audio and video cables. Unfortunately copper oxidation is a semi conductor and should be avoided because of the "skin effect" which causes high frequencies to use the outside of the conductor at high frequencies. If the outside of the conductor is oxidized, the performance at very high frequencies will suffer. Note: This is does not have any significant effect in the audio frequency range. (For more on Skin effect see the Article Library at Audioholics)
3. Gold has about 1.4 times the resistance of copper and does not oxidize making it a popular plating for audio and video connectors.
4. Tin is a poor conductor, with about 8.5 times the resistance of copper, but has good resistance to oxidation and the oxide has good conductivity. Tin is quite often used to protect copper from corrosion.
5. Nickel has about 4.5 times the resistance of copper, good resistance to oxidization and good oxide conductivity. Nickel is a very common connector plating.
6. Steel has about 7 times the resistance of copper, lousy resistance to oxidization and lousy oxide conductivity. Steel is generally used only on high frequency cables plated with copper that need very high strength.
TYPES OF WIRING AND THE "BIRTH" OF THE AUDIO/VIDEO CABLE
Discreet wiring - Discreet wiring is where separate conductors, indluding speaker wires, are run in some fashion (wires or circuit board traces) to the circuit components or input/output connections to which they need to go to. In some circuits, especially non signal related connections the path or interaction of these types of wires to one another is not particularly important as long as they are separated from one another to a reasonable extent. The closer they get, the more likely they are to possibly interact. This all goes out the window when a signal or "change" (whether they are due to ac power wire, analog signals or digital signals - basically any type of current or voltage change) becomes a part of the mix.
Example: Two wires are close together while another two wires are farther apart. The closer wires act more like a capacitor (have more capacitance) than the second two wires. If the circuit is in a quiescent state - "at rest" (no changes are going on) , there is potential energy storage due to capacitance, but without change, it has no effect on any signal, since there is no change. If you then create a change, or signal wire that causes electrical current flow, the two sets of wires may then have an effect on those changes, due to capacitance, inductance, etc, and the changes created may be different depending on the frequency of the signal involved and the characteristics of the wires and the overall circuit.
Example: A wire that has current flowing through it has a magnetic field. Two wires close together with current flowing through them both have magnetic fields. The two magnetic Fields will interact with one another if close enough and this interaction will effect the currents flowing through the wires more or less, depending on the rate of the change. If the wires are "send and return" signal wires the current flow will be opposite. If the current flow is opposite, the magnetic fields are in opposite directions.
Electromagnetic noise acting on these opposite fields are canceled out (dependent on the frequency and distance between conductors) - thus is born the improvement for signal transmission called the cable.
TYPES OF SHIELDING AND PROPERTIES:
Braids, Served Shields and Foil - A braid is as it sounds a "braiding" of conductor material that in this case surrounds the inner insulator and center conductor. Served shields are a layer of individual strands of wire which are laid one next to the other with a spiraling twist around the insulator and conductor. A foil is pretty much what it sounds like - an extremely thin, solid (not stranded) foil like shield surrounding the insulation and inner conductor and often inside and/or outside of another shield.
Coverage and frequency - A served shield does quite nicely for coverage at lower frequencies, at least until flexed, which will make them more noise susceptible. A braid is great for coverage and dual braids reach up to around 95% coverage. The tighter the braid the smaller the "holes" and the higher the frequencies need to be to penetrate the shield. Obviously, dual braids would end up with smaller holes, and a foil braid can provide up to 100% coverage. So why not just use foil? Isn't 100% perfect? No, because foils just don't give a stable, and consistent impedance over the length of the cable, durability, or consistency when flexed. Many extremely cheap audio and video cables are made with a simple foil shield - they break very easily and generally perform very poorly.
Triboelectric effects, microphonic effects (handling noise) - Flexing, twisting, or transient impacts on cables with the floor, etc, while in use will cause "snaps", "crackles", "pops" and other noises in the signal due to rapid changes of capacitance between conductors. This is generally regarded an audio problem, normally effecting microphone cords and guitar cords. Served shields are ideal for reducing triboelectric effects. The geometry is good at resisting large capacitive changes while flexed or impacted. Braids are generally not nearly as good as served shields for this, again due to their design. Movement, and compression will cause noise. Foils are the worst for this - they are easily deformed causing large changes in capacitance and large "pops" coming from PA systems. Any live sound PA system engineer or studio engineer Needs to be deeply knowledgeable about these effects and how to avoid them at any cost.
*Note - Steel Coat Hangers as Cable
While the typical crazies on forums suggest that coat hangers will operate just fine as an audio cable (and poorly designed tests concur) there are definitive reasons why it is not a remotely good choice. First of all, Steel is a very poor conductor with over 7 times the resistance of copper wire. That means lots of wasted power supply wire. Second, steel oxidizes easily and the oxidization is a poor conductor. Third, steel is rather hard to make into a twisted pair, allowing for EMI and RFI resistance. Without making the steel into a twisted pair, Noise and Hum may become a larger than desired portion of the sound!
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Applications for laser cleaning |
Posted by: fw115ww - 09-03-2021, 03:13 AM - Forum: Welcomes and Introductions
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From manufacturing plants and medical labs to the automotive, aviation, and steel fabrication industries, the laser is becoming the most preferred method for surface cleaning of materials.
Although the use of lasers in laser cutting machine, drilling, and laser welding machine applications is well known, its current adaptation in industrial cleaning applications is relatively new and unexplored.
This current application of lasers came as a result of the need for a nonhazardous, nonabrasive cleaning method that could be used as a substitute in applications where chemical, manual, and abrasive blasting methods were formerly used.
Benefits of using lasers in cleaning applications
Key problems presented by conventional cleaning methods include negative environmental impact and wear on the substrate. Abrasive blasting systems created significant amounts of waste and damaged delicate surfaces, while the use of chemical solvents resulted in potentially hazardous vapors and liquid waste products.
This led to the adaptation of laser technology in surface cleaning applications. Due to its many benefits, laser cleaning machine is now the most effective method of removing unwanted matter from the surface of materials.
Currently, there is a wide array of pulsed laser cleaning and de-coating systems used in various applications ranging from removing vulcanizing residue from tire molds and engraving surfaces by ablation to stripping insulation from conductors and de-coating paint from delicate surfaces.
Some of the many benefits of using lasers in surface cleaning applications include:
Automated and nonrandom cleaning method
Reduced amount of waste products
Increased safety
No need for chemicals or blasting media
Nonabrasive and noncontact cleaning process
Laser cleaning applications
Surface profiling and rust removal in steel fabrication. Portable laser cleaning machine is also an effective and efficient method for removing rust and scale from metallic materials. Rust and scale are contaminants that form on metal surfaces as a result of natural or artificial processes. When metals are exposed to moisture, they react with water to form ferrous oxides, resulting in rust. This rust degrades the quality of the metal, making it unsuitable for use in various applications.
On the other hand, scales form on metal surfaces as a result of heat treatment processes and its oxide discolors the metal surface, preventing any subsequent finishing operations.
Removing these unwanted surface deposits requires the execution of descaling processes to provide smooth surfaces for prefinishing and finishing processes such as electroplating.
Conventional rust removal and descaling operations involve the use of physical methods such as blasting, polishing, scraping devices, extra blows, and wire brushes. Chemical methods such as alkali descaling and acid descaling (pickling) can also be used for scale removal. However, these methods are very abrasive and result in environmental pollution and damage to the substrate metal.
To avoid these disadvantages, laser cleaning has become the preferred method for rust removal and descaling operations. The rust/scale is removed by directing a laser beam with high peak power and repetition rates on the rusted layer.
The industrial laser cleaning machine must be fired in short pulses to avoid damage to the substrate being worked on. The rust rapidly absorbs the energy of the laser beam, resulting in increased temperature levels. Once the temperature is sufficiently high, the rust melts and eventually vaporizes.
Using pulsed fiber lasers is the preferred option since it provides greater control over power, wavelength, and pulse duration, allowing the rust/ scale to vaporize without any damage to the underlying material.
The laser cleaning process can also be applied to surface profiling. Before protective coatings can be applied to fabricated steel parts for preservation and protection from corrosive action, their surfaces must be clean and free from all contaminants.
Surface profiling/preparationentails the removal of all contaminants from the surface of steel parts in preparation for protective coating applications. These contaminants include oil, grease, scale, hydrates and oxide layers, shop-primer, etc. For any subsequent processes, the bars, wires, and profiles must also be free from these contaminants.
Since fiber laser cleaning uses a nonabrasive, noncontact approach without the involvement of solvents, chemicals, or abrasive media, it is ideal for surface profiling and rust/scale removal. The cleaning process can be conducted on a small or large scale and can be automated. Precision laser cleaning machine is an environmentally friendly and cost-effective way to remove rust and prepare the surfaces of rolled steel products and fabricated steel parts for protective coating.
Anode assembly cleaning. The aluminum smelting industry uses carbon blocks as "sacrificial" anodes in the production of primary aluminum. The quality of the anode has an impact on the environmental, economic, and technological aspects of aluminum production. A small percentage of cell power is devoted to overcoming the electrical resistance of prebaked anode.
The presence of dirt and other contaminants will increase the anode's electrical resistance, resulting in the consumption of more cell power. The presence of contaminants also reduces the lifespan of the anode by increasing its rate of consumption during the smelting process. From the standpoint of efficiency, it is necessary to clean and remove all surface contaminants from anode assemblies before they are used in aluminum smelting operations.
In addition, anode assemblies are valuable tools that can be reused, but only after executing a thorough and careful treatment of its main components—under specific conditions.
Laser cleaning meets the specific conditions under which anode assemblies can be treated for reuse. It can be used in the following applications:
Removal of residue from carbon butts
Cleaning of cathode bars
Removal of contaminants and dirt from thimbles and stub rods
Adhesive bonding preparation for metals. To increase process stability, surface adhesion, and better seam quality, the surface of the metallic materials to be joined must be prepared before the application of welding and other joining techniques.
Without the necessary groundwork, joints and seams become susceptible to degradation, increased wear, and catastrophic failure. Laser cleaning can be used to prepare surfaces before they are joined, resulting in excellent bond strength quality for improved corrosion resistance and durability.
Laser cleaning is suitable for adhesive bonding preparation since it removes oxides and other contaminants such as grease and oxides that reduce the strength of adhesive bonds. It is particularly suitable for applications involving curved or flat surfaces or parts with certain limitations for highly complex 3D geometries.
One of the major benefits of laser cleaning is the ability to fine-tune its power and wavelength for precise modification of metals such as magnesium and aluminum to be used for microstructuring purposes. It also endows materials with very high resistance to corrosive elements, ensuring stable, long-lasting adhesive bonding.
In recent times, there is an increased use of adhesive bonds in structural design applications in place of conventional joining techniques such as riveting and welding. This is attributed to the many advantages of adhesive bonding over conventional techniques.
These advantages include uniform stress distribution, corrosion reduction, structure lightening, vibration attenuation, and acoustic insulation. However, these benefits can only be achieved if the surfaces to be bonded are prepared, degreased and carefully cleaned.
Laser cleaning is ideal for such applications since it carefully removes oils, rust, protective coatings and other contaminants resulting from shipping without harm to the underlying substrate.
Pretreatment for brazing and welding. Laser cleaning has also proven effective in pretreatment applications for welding and brazing. Before aluminum and steel materials are used for welding purposes in shipbuilding, precision tool manufacturing, automotive, and other related industries, their surfaces must first be prepared.
Laser weld preparation is one of the many applications of laser cleaning and handheld laser welding machine and helps to remove ferrous and nonferrous metals, lubricants, and other contaminants from metal and aluminum surfaces in preparation for high-quality welds. It also ensures smooth and pore-free brazed seams.
When used in pretreatment processes for welding and brazing, laser cleaning does the following:
Thorough removal of shop-primer, hydrates, and oxide layers
De-greasing and de-oiling
Apart from welding and brazing preparation, lasers can also be used to remove weld residues such as residual flux and oxide materials as well as thermal stains from finished weld joints. This cleaning method is particularly beneficial for stainless steel parts since laser light suspends grain boundaries, ensuring that weld seams are passivated—thus increasing corrosion resistance.
The benefits of using laser cleaning in welding and laser marking machine and brazing pretreatment applications include:
Adjustable wavelengths and power for precise treatment of joining surfaces over a wide range of material thicknesses
No damage to the underlying substrate—that is, the galvanized layers of sheet steel
Partial decoating. Laser cleaning is particularly effective in applications that require the partial removal of paint or coatings from finished surfaces. It can be used on virtually all surface types, whether chemically anodized, oxidized, or organic. Laser cleaning can be used to de-coat solar panels and remove paint in the automotive and aerospace industries while maintaining the integrity of the primer substance.
In de-coating applications, fiber lasers are the preferred option. They obviate the need for masking by precisely removing the layer of coating in the specified area, thus eliminating some of the challenges inherent in partial de-coating applications. Lasers can be used in:
Precise treatment for functional and design surfaces
Creating Faraday cages and continuity contacts for the aerospace industry
Partial removal of paint for electromagnetic compatibility
Produce bond points for wire connections
Strip coating in the electronics and automobile industry
Laser cleaning is highly effective in situations where critical weld seams on painted structures/parts must be de-coated for inspection purposes. The laser removes the coatings without the need for hand or power tools, abrasives, or chemicals that can hide the problem areas and cause further damage to the surface.
Selective paint removal. Selective paint removal represents one of the many applications of laser cleaning. In the automobile and aerospace industry, it is sometimes necessary to remove the top layer of paint while maintaining the primer. This is often the case when the top weathered coatings on vehicles need to be thoroughly removed before the application of a new paint finish.
Since the top layer of paint is physically and chemically different from the underlying primer, the power and frequency of the laser can be set to a frequency that only removes the top layer of paint.
The primer remains intact since the laser has no mechanical, chemical or thermal effect on it. This ensures the maintenance of the primer's corrosion resistance ability. When bare metal-to-metal contact is required for electrical continuity between parts, the laser cleaning process is preferred since it saves time and materials while improving the quality of the finished surfaces.
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Top Benefits Of Herbal Extracts |
Posted by: fw115ww - 09-03-2021, 03:12 AM - Forum: Welcomes and Introductions
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The health benefits of plant-based supplements have been known for centuries. In fact, the use of herbal medicines is said to date as far back as 60,000 years – long before the advent of modern medicine.
Used in cuisines all over the world, some of the most well-known herbs and fruits are blessed with natural herbal extract compounds that are advantageous to human wellbeing. Specifically, these are packed with bioactive compounds, such as polyphenols, which are linked to antioxidant activity in the human body.
The question is, then, what’s the point of liquid herbal extracts – like Comvita’s Olive Leaf Extract which is known for its antioxidant effects?
While eating fresh fruits and vegetables and adding herbs to your food are an important part of a healthy, well-rounded diet, here are some of the top benefits of supplementing your diet with liquid extracts.
POTENCY
Plants in their raw form don’t contain the same concentration of beneficial antioxidant compounds as you’ll find in liquid herbal extract – in fact, it’s vastly different..
So, consuming liquid herbal extract in addition to a healthy balanced diet is a convenient way to give your a top up of beneficial antioxidants without trying to eat impossible amounts of herbs, fruits and vegetables.
EASY TO CONSUME AND VERSATILE
It’s important to maintain a healthy diet, but it can be tricky to ensure you’re incorporating all of nature’s most precious compounds into an everyday diet.
Olive Leaf Extract can be taken alongside your daily meals to get the benefit of their nutrients and antioxidant compounds. For example, you could add the recommended amount of olive leaf extract to drinks such as water, juice and tea.
For a long time, extraction has long been a popular method for getting the beneficial nutrients and compounds out of plants and herbs. For the most part, this has traditionally been done using hot water to make a ‘tea’.
But while extraction methods have continued to evolve, Comvita has remained dedicated to preserving freshness and natural processes. Comvita Olive Leaf Extract is not extracted with alcohol and uses only freshly picked olive leaves in the extraction process which takes place onsite at our Queensland olive tree grove. You can find out more about our Olive Leaf Extract here.
Cosmetics are products designed to cleanse, protect and change the appearance of external parts of our bodies, like food additives in food industry. The key cosmetic ingredients present in most cosmetics include water, emulsifiers, preservatives, thickeners, moisturisers, colours and fragrances. Ingredients can be naturally occurring or artificial, but any potential impact on our health depends mainly on the chemical compounds they are made of. The doses of potentially dangerous chemicals found in cosmetics are considered too small to pose a risk to human health.
Natural products, such as natural fruit and vegerable powder, used to be sold primarily in health food stores and farmers markets with labels decorated with pictures of leaves. It was a very specific niche and not taken seriously by the beauty industry. But now sleek new brands positioning themselves as “cleaner” alternatives to the mainstream are exploding.
Daniela Ciocan — the marketing director at Cosmoprof North America, an entity that hosts a large expo where brands can display their wares in hopes of landing retail placement — says that thanks to retailer and customer demand, this year the organization doubled the amount of space it dedicated to new “clean” brands at the 2017 convention.
In the past 12 months, so-called natural brands like Tata Harper and Jessica Alba’s Honest Company products with natural color have made up about a quarter of all higher-end skin care sales, according to the NPD Group. The category is growing at a faster rate than last year.
“We’re absolutely inundated,” says Annie Jackson, a co-founder of Credo, which was dubbed the “Sephora of clean beauty” when it launched in 2015. It currently has eight stores in the US and a robust online business, where it sells about 115 brands. Credo receives about 200 new products a month from brands hoping to sell there.
And it has a competitor. Follain, which opened before Credo in 2013 as a local shop in Boston, is growing rapidly. It currently has five stores, will open two more in October and expects to have 10 by the end of 2019. Its growth rate is up more than 200 percent in 2018.
In the meantime, customer demand means mainstream companies and retailers are giving more lip service to the concept of clean beauty. In 2017, Target bumped up its natural beauty offerings. CVS announced it was removing parabens and other ingredients from 600 of its house-branded products by the end of 2019. Brands regularly remove parabens and sulfates and the like, sometimes quietly and sometimes with great fanfare.
Sephora launched its “Clean at Sephora” initiative in May, citing in-house research that revealed that 54 percent of its skin care shoppers think it’s important that their products “have a point of view on clean” and looking to shop brands that are “grounded in a ‘free of’ ingredient perspective,” according to Cindy Deily, the senior director of skin care merchandising at Sephora, though she did not say free of what. Sephora received some criticism that its clean standards weren’t as rigorous as they could be, but Deily says the “no” list is still evolving.
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What is natural soap made of? |
Posted by: fw115ww - 09-03-2021, 03:11 AM - Forum: Welcomes and Introductions
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Our definition of natural soap is one made of oils, fats and butters that have been mixed with lye. A completely natural soap should also be coloured naturally as well, to adhere to the definition of a natural soap.
Soap is made through the process of saponification. This is where lye (a mix of either Sodium Hydroxide or Potassium Hydroxide and water) is mixed with oils, fats and butters to turn the oils into salts. It is a chemical reaction where the triglycerides of the fats and oils react with the lye.
This reaction is an exothermic one, which means that it produces heat. The amount of heat used to produce the nature soap will determine whether it is hot or cold process soap. The majority of natural soaps are made using the cold process method.
Cold process soap is made by as the name suggests keeping the soap cooler. Usually the temperature of cold process soap will be around 120 degrees Fahrenheit. Still quite hot, but cooler than the hot process.
Cold process soap is easier to pour as it is generally still very liquid when the mixing of the soap has finished. It also yeilds a bar that looks fresh and clean cut and generally more aesthetically pleasing.
Hot process soap like the name suggests is made at a higher temperature, which for most soap makers will be around 150 degrees fahrenheit or hotter. Extremely hot and you would know about it if you got any spilt on you.
Hot process soap is less easy on the eye as it is harder to pour into a mould. Let's just say if you like the rustic look then you will like hot process soap better than the clean cut of cold process soap. Hot process takes only 1-3 weeks to cure as most of the water has already left it in the process, where as cold process will take from 4-6 weeks to cure.
Once the saponification has happened and the raw soap has been poured into the mould, it will take around 24-48 hours for the process to be complete. The soap will then have to cure for a set amount of time which will depend on which process was used but can range anywhere from 1 week to 5 years.
Benefits of natural soap
Natural soaps are great as skin care products and they have some amazing benefits for the skin. Let’s look at the benefits of natural hand soap and what it can do for your skin.
Benefits of Natural soap include:
Moisturising
Natural soap bars naturally produce an ingredient called glycerin. This ingredient is highly prized for its moisturising abilities and in the over the counter soaps you usually find in supermarkets and pharmacies, this ingredient is removed and sold on. Natural soaps tend to contain a lot of glycerin which is why they are so moisturising, and they are perfect as bath gift sets for kids.
Gentle
Natural soap bars are generally gentler on skin than common soaps found in the shops. They contain no drying chemicals such as sodium lauryl sulphate which can strip the skin of its natural grease and cause excessive water loss. This causes the skin to dry out. Natural soaps with glycerin are less aggressive in their cleaning action and also contain moisturising glycerin to draw moisture back towards the skin.
Enviromentally Friendly
Natural soaps are a great way to be more green. By using a natural skin care soap instead of a plastic packaged shower gel, your saving a lot of plastic from ever being created. You are also preventing lots of the chemicals used in over the counter soaps from getting back into the environment.
One of the chemicals used in antibacterial soaps turns into a dioxin when exposed to sunlight and these carcinogenic dioxins are being found in higher densities in our drinking water. Find out more in our dedicated article on antibacterial soap here.
Smells great
True natural soap bars are made with essential oils rather than fragrance oils. Essential oils come directly from the plant and thus smells like the scent you would know from nature. They also have a wide array of natural benefits for the skin and body.
No Chemicals
Natural soaps don’t contain any synthetic chemicals. Chemicals used in over the counter soaps can cause the skin to dry out and can possibly lead to eczema. Also natural soap contains essential oils for scents rather than fragrance oils.
Fragrance oils can contain over 100 different chemicals within them, including parabens and phthalates. These chemicals are potential carcinogens and are used to enhance the scents and increase shelf life.
Better Ingredients
Natural handmade soaps tend to be more expensive than over the counter bars of soap. One of the main reasons for this is that natural soaps usually contain better ingredients. For instance most bars bought from a supermarket will contain palm oil and cheap chemical ingredients such as sodium laureth sulphate.
Both are very cheap, not great for skin. On the other hand natural soaps usually but not always tend to have more expensive ingredients which are better for skin such as olive oil, cocoa butter and hempseed oil.
These ingredients make a more moisturising bar, but the ingredients are generally more expensive than palm oil and chemicals used in soap making, but with these come greater benefits for the skin.
Natural soaps have many benefits and each will have slightly different benefits depending on the oils chosen. For instance our soaps have been specifically designed for dry skin, as they contain lots of glycerin and emollient ingredients which aid the skin in retaining moisture. Other natural soaps will do different jobs depending on how they have been formulated.
In general natural soaps are really amazing for baby skin care and we know ours are great for dry skin as we specifically designed them to be this way!
What properties do natural soaps have?
A good natural soap will be made of a variety of ingredients. This is because different oils fats and butters will have different properties that they will bring to a soap. The properties we look for in soap making are:
Hardness
For instance if you were to make a bar out of pure cocoa butter (a very hard butter) then your soap would be extremely hard, unlike if you were to make a soap out of pure sunflower oil which would then give you a very soft bar.
The only exception to the rule is castille soap which traditionally is made out of purely olive oil. This soap is named after the region in Spain where it originates. Once this soap is made it is extremely soft, which is why traditional castile soap is cured for a long time; approximately 5 years.
During the curing process the soap loses moisture content and gradually gets harder. This is unusual as most cold process soaps will take around 4-6 weeks to cure and hot process around 1-3 weeks.
Hardness is important in a bar because it determines how long a bar will last. Harder bars will last for a long time, whilst softer bars will not last as long. It’s important to get a balance and a good level of hardness in a soap bar, but this is not the only quality we need.
Some of the oils, fats and butters you can use to make a harder soap are animal fats such as lard and tallow. Other vegan options you can use to make your soap hard include cocoa butter, shea butter, coconut oil and palm oil.
Cleansing
This is the cleaning properties of the soap. This is important as it is the soap’s main job. Some of the oils, fats and butters used have cleansing properties.
These cleansing properties leave the skin clean and unlike soaps that contain sodium lauryl sulphate or derivatives of it. These soaps, shower gels (including bath bomb) and hand washes will clean your skin as they are a chemical surfactant, but they will also rinse away the natural grease your skin produces.
This natural grease is what plugs the gaps between the skin cells, and stops moisture loss from the skin. When you use these chemical based soaps the surfactant will dry your skin, causing damage and exacerbating dry skin conditions such as eczema and psoriasis. They can also cause your skin to over react and produce large amounts of natural grease which clog skin cells and can lead to acne.
Cleansers in soap include coconut oil and palm oil among others. These oils should be used in soap sparingly, as soaps with a large proportion of these oils will cause the skin to dry out. These oils should always be below 40% of total oils used in soap. When these oils are used in high amounts like a lot of the soaps you can buy at the supermarket, they can leave your skin feeling dry and rubbery.
A lot of soaps you can buy on the high street are made using majority palm oil or palm kernel oil which are cleansers and will explain why you are left feeling dry and rubbery after washing.
One additional drawback of palm oil in soap is it produces a very small amount of glycerin during the soap making process. Glycerin is a humectant which means it draws moisture to your skin, this is hugely important in natural soap as the glycerin will leave your skin feeling moisturised and soft after washing.
When you use super cleansing soaps with palm oil in or sodium lauryl sulphate then your skin will feel dry and lose moisture fast. The benefit of using our natural soap with a blend of natural ingredients is we have formulated a bar of soap which will clean you but also leave your skin feeling soft and moisturised.
Conditioning
This is an important quality in soap as it conditions and moisturises your skin soft. Conditioning means the soaps emollient content. An emollient is something that helps the skin retain moisture. They also sooth the skin and keep it moisturised and soft.
Conditioners include: olive oil, apricot kernel oil and hempseed oil. Two of those ingredients are included in our soap as they have amazing skin benefits. They leave your skin conditioned and soft. I like to think of the conditions in soap, as similar to a conditioner for hair. After you have used your shampoo, your hair may feel slightly dry, when you use conditioner it softens the hair and makes it feel silky.
This is the same in soap. The coconut oil in our soap will clean your skin, and then the olive oil and hempseed oil will then condition your skin leaving it feeling soft and moisturised.
As well as the conditioning properties of our soap, we also like to keep all of our glycerin in our soap. A lot of the soap sold on the high street or out of the supermarket are made by large brands.
These large brands take the glycerin out of their soap. This is a relatively simple process of separating the soap through the use of salt water and boiling off the salt water to leave the glycerin.
This is another quality in soap we love. When your soap produces a rich creamy lather, it feels nice on the skin, suitable as adult skin care.
Creaminess and bubbles are a compromise you need to make when formulating your soap recipe. When you have a soap which produces a lot of large bubbles then it will not feel creamy, where as when you have a very creamy soap you will have very small bubbles.
Creaminess is important in soap as it feels luxurious, which is what you want when you are using a luxury natural soap. Creaminess has no real benefits to the skin, it’s more of a benefit to the experience of using the soap.
If you enjoy a luxury soap, especially if it contains natural essential oils and smells amazing, then you will benefit from the soap by feeling, relaxed, de-stressed and treated to a luxury experience. This is why we hold creaminess in such high regard, even though it has very small benefits to the skin.
Bubbly
Again one of the properties of soap which may not provide an actual benefit to your skin, but adds to the psychological benefit of using a soap. Oils that produce a lot of bubbles are popular to use in natural soap. In particular coconut oil and castor oil can produce larger bubbles when used in soap.
Bubbles have no real benefit in soap, large or small the soap will be good for your skin if it is a good blend of oils. But lets not underestimate the benefit of bubbles in soap, the psychological effect of bubbles is so important in soap that larger companies have ensured their soap, hand wash and shower gel produce them regardless of hard or soft water.
One of the main reasons larger companies use sodium lauryl sulphate and derivatives of this chemical is that it is a foaming agent.
People generally associate bubbles with cleanliness. But this is not always true. Soap will still work even if it has no bubbles because soap loosens dirt from the skin and allows it to be washed away.
In our soap, we use coconut oil to produce bubbles. This natural cleanser also has the properties in soap that allows it to produce large stable bubbles adding to a creamy lather and increasing the satisfaction in using our products.
Well something that we feel quite strongly about is how a soap is scented.
Soap can be made naturally and then scented with something in the industry we call fragrance oil. This fragrance oil is synthetic, which means it is made artificially. In brutally blunt terms, it’s made with chemicals. There may be a natural element to it, but it will have chemicals and additives to it to enhance the smell and also its shelf life.
This is because during the soap making process the actual process can dilute the smell and make it weaker. This is why companies use fragrance oils as they are usually chemically enhanced to smell stronger, especially through the saponification process.
When you use natural essential oils they tend to lose their smell in the process unless you use large amounts. In the EU and United Kingdom the maximum amount of fragrance you can use is 3% of total mixture.
This is another reason why companies use fragrance oils, as they are stronger and you will only use a small amount for a similar result. Again this shows you profit margins are more important to large companies than your skin.
Fragrance oils are protected under EU law. The manufacturers do not have to disclose the ingredients included in the fragrance. This is for fear their competition will copy their recipe. Whilst this may be the case, I think the consumer would like to know what exactly they have been putting on their skin.
Fragrances or perfumes are made by combining a number of ingredients, of which the raw materials can be in many forms such as liquid, solid, crystalline etc. To combine these ingredients they use phthalates, which is a type of solvent to dissolve these ingredients all into liquid form.
Phthalates have been linked to a multitude of diseases and disorders including asthma, ADHD, obesity and even breast cancer.
Having used fragrance oils at the start of our soap making journey and accidentally spilling some on our scales, I initially though, no problem I’ll just wipe it up.
After wiping, spraying with antibacterial spray, white spirit and iron wool wouldn’t remove it, we made the conscious decision to only use natural essential oils in our soaps. Something that cannot be removed by such a serious amount of cleaning chemicals and effort surely can’t be good for skin. There are also novel soaps like fruit shaped bath bomb.
I can confirm essential oils are much easier to clean up if spilled as they are completely natural. Essential oils come directly from the fruit or plant and are produced by either squeezing them out of the organic material or distilling them.
Plus they also have some amazing natural benefits which we have listed on all of our product pages.
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Balloon Inflator Pumps: The Definitive Guide to Choosing and Using them |
Posted by: fw115ww - 09-03-2021, 03:09 AM - Forum: Welcomes and Introductions
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This article will present the definitive guide to choosing and using balloon inflators as you prepare to create your next masterpiece balloon decoration.
Inflating balloons can be a tiresome activity if you are inflating more than two balloons with air from your lungs. Fortunately, manual balloon pumps and electric balloon inflators make this process a breeze.
The Old Way of Inflating Balloons
So you are having an event, maybe a party and you want to decorate using balloons. As you consider inflating tens of balloons with your lungs, you may be dreading the consequences: sore cheeks, painful jaws, tired arms, aching lungs, and chest, just to name a few. The old method required time, people, patience, and determination.
The solution to the problem of inflation
A solution to your problem is here. Thankfully it is the dawn of a new era; balloon inflators have now become extraordinarily cost-effective and accessible to the DIY person or balloon decorator. These devices exponentially reduce the time and effort required to inflate a large number of balloons. It takes approximately 10 pumps on a double-action balloon pump to fully inflate a balloon and about 3 seconds to do the same using an electric balloon pump. So now, you are free to create your balloon arches, garlands, stands, centerpieces, and backdrops for your special events.
What is a Balloon Pump?
A balloon pump or inflator is a device that makes filling balloons with air faster and more efficient. Balloon Pumps are either manually or electric balloon pump. A balloon pump is designed with a special nozzle that can securely hold the balloon in place during inflation.
Types of Balloon Pumps
There are various types of balloon pumps, they are primarily separated into manual and electrically operated pumps:
Manual Hand-operated Balloon Pump/Inflator
A manual hand inflator is a cylindrical device with a handle connected to a shaft. The shaft is attached to a disc that extends to the edges of the tubular body of the pump. The pump is operated by using the handle to force air through the connected nozzle. There are two additional categories of manual inflators:
Single Actions Balloon Pump
A single-action balloon inflator will only push air through the nozzle into the balloon on the forward stroke. The reverse stroke will refill the pump with air. This is great for a small number of balloons.
Dual or Double Action Balloon Pump
A Double action manual balloon pump can inflate a balloon on both the forward and reverse stroke. Making the process twice as efficient for the same amount of energy you put out. This is great for inflating an average number of balloons for a small event.
Electric Balloon Pump(AC air pump, DC air pump)
An electrically operated balloon pump uses a motorized pump to quickly send high volumes of air through its nozzle to fill the balloons. They deliver significantly more air in a shorter time when compared to a manual pump with practically no effort. Many are even outfitted with as many as four nozzles to support the inflation of multiple balloons at once. This is great for a large number of balloons and a big event.
When choosing between manual and electric balloon pumps, you have to take several things into consideration.
How much are you willing to spend?
An electric balloon pump can be more than 5 times the cost of a manual inflator. That price does not include the professional balloon pumps that can pump all ballons to the same size, adjust pressure settings, or the ones that come with a portable battery. Those can go upwards of 20 times the cost of a manual balloon pump.
How Many Balloons do you need to inflate?
If your balloon arrangement has more than 200 balloons, it may make sense to get an electric balloon pump. At this many balloons, it becomes a physical workout to use a manual balloon pump. However, if you have the time and the energy, you can consider it your arm workout for the day. You can even share the task between more than one person to lighten the effort.
Is this a one-off activity?
If you are planning to create large, multi-hundred balloon arrangements regularly. It will probably make more sense to invest in a reliable electric balloon pump. Not only will it require less time and effort, but most manual ballon pumps are made of plastic; frequent usage can cause the pump to become brittle, and the handle tends to break from overuse. This can be mitigated if you have multiple hand pumps, but for efficiency, an electric pump is more advantageous.
Will you have access to an electrical outlet.
For outdoor balloon decoration setups that are far away from an electrical outlet, a manual hand pump is the most ideal tool for the job. You can pull it out on the spot and inflate as many balloons as you need without going back and forth to an electrical outlet. Even though it is the most convenient way to inflate balloons for outdoor use, it is by no means the only way.
You can use large garbage bags and inflate your balloons ahead of time then transport them to your outdoor location. You can invest in a very long extension cord that will provide the reach you require. If you have a vehicle nearby, you can use an electrical inverter to power your balloon pump from your vehicle. You can also utilize the long extension cord there as well. The final method is to invest in a battery-powered electric pump. Battery-powered electric inflators are rechargeable and portable and can cost a pretty penny for these extra features. However, sometimes the investment may be worth it if you need the advantage of portability and the power and ease of an electric pump.
Is your environment noise friendly?
Electric balloon inflators are noisy. This is due to the powerful motor it uses to inflate balloons quickly and at high pressure. If you are setting up a balloon arch at daycare during nap time, you might want to opt for your manual balloon hand inflators.
How fast do you want to work?
In the time it takes to inflate one balloon using a double-action balloon pump, you can inflate 4 using a two-valve electric balloon inflator. Electrical inflators are fast and powerful. If you need speed and power, electric battery air pumps are the right choice.
How many people are working along with you?
If you have multiple people working on your balloon decoration project, you can choose between a electric or a hand air pump. Various people using their own hand-operated balloon inflators can work out well in terms of a balance for the cost and speed you may need. This is the least expensive and most efficient use of a manual balloon inflator.
Electric rechargeable air pumps can also use multiple people at the same time. Depending on your pump type, electric balloon pumps can have as many as 4 active valves used to inflate balloons simultaneously. This will increase your efficiency.
How strong are you?
Manual balloon inflators require an average amount of physical strength to inflate a large number of balloons. A good quality hand-held balloon pump will be well lubricated. It should not provide much friction when pumping air into the balloons. However, if this is not the case, or if the lubrication has somehow dried up, it will take added energy to inflate balloons with a manual pump.
Children should generally have little to no problem using a manual balloon inflator if it is well-lubricated. An electric balloon pump takes limited effort more than the strength to hold the balloon in place as it is inflated.
Multipurpose usage
Due to the design, portability and lightweight of the hand balloon pump, it can be easily used to inflate other inflatables such as pool float toys, exercise balls, inflatable toys like the Rody Horse, and even small sleeping mattresses. Manual Balloon pumps can also be used to blow dust from hard-to-reach crevices instead of purchasing a can of compressed air.
Helium Balloon Inflator
Helium balloons do not require a balloon pump since helium is usually stored in a cylinder in compressed form. Balloons are then simply inflated by opening a valve attached to the cylinder of compressed helium.
Where to buy
The cost of balloon inflators has reduced over the past couple of years. You can get professional level pumps, such as high pressure air pump, for a fraction of the price.
Inflatable paddle boards are typically quick and easy to inflate, and many of them come with a manual pump that can inflate a SUP in about 10 minutes. However, younger or much older SUPers might find inflating them difficult, while others just want to spare themselves from the strain and sweat that comes with manual pumping. Alternatively, if you’re heading to the lake to get some yoga or meditation in, having to put so much time and work in inflating a SUP electric pump doesn’t exactly put you in a peaceful mindset.
That’s why our number one recommended accessory for all inflatable paddle boarders is an electric pump. An electric pump can inflate your paddleboard just as fast as a manual pump, but without the effort of having to do it yourself. Electric pumps can also help finish deflating your iSUP for you, making sure all the air is out and it can be packed up super tight at the end of the day. Some electric pumps are also smaller and weigh about the same asn traditional manual pumps, making them easier to pack and carry as well. Some electric pumps even come with an integrated or portable battery, meaning you don’t even have to be near a car to use them.
An electric pump is better than a manual pump in almost every way, with many of them available for less than $150. However, just like SUP pump, there are a ton of electric pumps to choose from.
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What is CNC Machining? |
Posted by: fw115ww - 09-03-2021, 03:06 AM - Forum: Welcomes and Introductions
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The term CNC stands for 'computer numerical control', and the CNC machining definition is that it is a subtractive manufacturing process that typically employs computerized controls and machine tools to remove layers of material from a stock piece—known as the blank or workpiece—and produces a custom-designed part. This process is suitable for a wide range of materials, including metals, plastics, wood, glass, foam, and composites, and finds application in a variety of industries, such as large CNC machining, machining of parts and prototypes for telecommunications, and CNC machining aerospace parts, which require tighter tolerances than other industries. Note there is a difference between the CNC machining definition and the CNC machine definition- one is a process and the other is a machine. A CNC machine (sometimes incorrectly referred to as a C and C machine) is a programmable machine that is capable of autonomously performing the operations of CNC machining.
Subtractive manufacturing processes, such as CNC machining, are often presented in contrast to additive manufacturing processes, such as 3D printing, or formative manufacturing processes, such as liquid injection molding. While subtractive processes remove layers of material from the workpiece to produce custom shapes and designs, additive processes assemble layers of material to produce the desired form and formative processes deform and displace stock material into the desired shape. The automated nature of CNC machining enables the production of high precision and high accuracy, simple parts and cost-effectiveness when fulfilling one-off and medium-volume production runs. However, while CNC machining demonstrates certain advantages over other manufacturing processes, the degree of complexity and intricacy attainable for part design and the cost-effectiveness of producing complex parts is limited.
While each type of manufacturing process has its advantages and disadvantages, this article focuses on the CNC machining process, outlining the basics of the process, and the various components and tooling of the CNC press machine. Additionally, this article explores various mechanical CNC machining operations and presents alternatives to the CNC machining process.
Overview of CNC Machining Process
Evolving from the numerical control (NC) machining process which utilized punched tape cards, CNC machining is a manufacturing process which utilizes computerized controls to operate and manipulate machine and cutting tools to shape stock material—e.g., metal, plastic, wood, foam, composite, etc.—into custom parts and designs. While the CNC machining process offers various capabilities and operations, the fundamental principles of the process remain largely the same throughout all of them. The basic CNC machining process includes the following stages:
1. Designing the CAD model
2. Converting the CAD file to a CNC program
3. Preparing the CNC machine
4. Executing the machining operation
Hydraulic mechanism
Hydraulic cutters, including swing arm cutting press, utilize a hydraulic mechanism to close the scissors’ hardened steel blades. Oil under high pressure (around 700 bar) is pumped to the movement mechanism to deliver enough power to cut even the hardest materials. The hydraulic cylinders of some cutters are filled through an external pump, while others have an electric pump with a battery integrated in the scissors’ handle. Each type has its advantages and disadvantages. Read on to find the type of hydraulic cutter that is most suited for your job.
Mobile hydraulic cutters
Holmatro’s mobile hydraulic cutters are specially designed to be used on site. Examples include the dismantling of buildings, cleaning up of industrial cables, and the remediation of gas stations. For those kind of purposes, mobile cutters are made with easy handling and portability in mind. The electric and fuel-driven mechanisms in Holmatro’s mobile cutters are lightweight and compact. The brand also offers models with batteries, which are specially designed to work in hard to reach places. The durable yet lightweight aluminum construction of most mobile cutters makes them easy to handle and carry around.
Stationary hydraulic scissors
In contrast to mobile cutters, stationary cutters are made for continuous use on a fixed worksite. These hydraulic cutter machines are often used in production processes, and in the recycling of cars and household appliances. Because of this, stationary cutters are developed for maximum durability and frequent use. The machines are largely made from high-grade steel, which results in a higher weight. Thanks to a so-called balancer, however, the weight does not rest directly on the user and a great ease of use is maintained.
Automatic Travelling Head Cutting Press
Where high speed output with predictable accuracy and material yields are needed, move up to a GCT automatic travelling head press.
Cutting jobs and patterns are pre-programmed into the machine’s computer or this can be carried out off-line and information sent down to the machine.
Thus, the operator has no more to do than load the material and cutting tool and gather the cut pieces as they emerge from the machine – the machine dictates the speed, accuracy and material yield.
In all cases, the cutting tool, such as swing arm cutting press, is loaded onto the machine’s cutting head which, on 3 axis models, can be rotated to obtain the best fit or interlock of cutting patterns. Cutting can be onto a polypropylene cutting board for easily fed material but the most versatile model uses a moving cutting and feeding belt. This acts both as a cutting barrier and as a conveyor to carry the cut components away from the cutting area.
For work which is exclusively in sheet form a version is available with a powered, mobile, feed table – very popular in the envelope industry.
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Understanding Metal Stamping |
Posted by: fw115ww - 09-03-2021, 03:05 AM - Forum: Welcomes and Introductions
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Metal stamping is a cold-forming process that makes use of dies and stamping presses to transform sheet metal into different shapes. Pieces of flat sheet metal, typically referred to as blanks, is fed into a sheet metal stamping press that uses a tool and die surface to form the metal into a new shape. Production facilities and metal fabricators offering stamping services will place the material to be stamped between die sections, where the use of pressure will shape and shear the material into the desired final shape for the product or component.
This article describes the metal stamping process and steps, presents the types of stamping presses typically employed, looks at the advantages of stamping parts compared to other fabrication processes, and explains the different types of stamping operations and their applications.
Basic Concepts of Metal Stamping
Metal stamping, also referred to as pressing, is a low-cost high-speed manufacturing process that can produce a high volume of identical metal components. Stamping operations are suitable for both short or long production runs, and be conducted with other metal forming operations, and may consist of one or more of a series of more specific processes or techniques, such as:
1. Punching
2. Blanking
3. Embossing
4. Coining
5. Bending
6. Flanging
Punching and blanking refer to the use of a die to cut the material into specific forms, such as pole line hardware. In punching operations, a scrap piece of material is removed as the punch enters the die, effectively leaving a hole in the workpiece. Blanking, on the other hand, removes a workpiece from the primary material, making that removed component the desired workpiece or blank.
Embossing is a process for creating either a raised or recessed design in sheet metal, by pressing the raw blank against a die that contains the desired shape, or by passing the material blank through a roller die.
Coining is a bending technique wherein the workpiece is stamped while placed between a die and the punch or press, such as sheet metal fabrication. This action causes the punch tip to penetrate the metal and results in accurate, repeatable bends. The deep penetration also relieves internal stresses in the metal workpiece, resulting in no spring back effects.
Bending refers to the general technique of forming metal into desired shapes such as L, U, or V-shaped profiles. The bending process for metal results in a plastic deformation which stresses above the yield point but below the tensile strength. Bending typically occurs around a single axis.
Flanging is a process of introducing a flare or flange onto a metal workpiece through the use of dies, presses, or specialized flanging machinery.
Metal stamping machines may do more than just stamping; they can cast, punch, cut and shape metal sheets. Machines can be programmed or computer numerically controlled (CNC) to offer high precision and repeatability for each stamped piece, and this technology is widely used in furniture hardware. Electrical discharge machining (EDM) and computer-aided design (CAD) programs ensure accuracy. Various tooling machines for the dies used in the stampings are available. Progressive, forming, compound, and carbide tooling perform specific stamping needs. Progressive dies can be used to create multiple pieces on a single piece simultaneously.
Types of Stamping Operations
Progressive die stamping
Progressive die stamping uses a sequence of stamping stations. A metal coil is fed into a reciprocating stamping press with progressive stamping dies. The die moves with the press, and when the press moves down the die closes to stamp the metal and form the part. When the press moves up, the metal moves horizontally along to the next station. These movements must be precisely aligned as the part is still connected to the metal strip. The final station separates the newly-fabricated part from the rest of the metal. Progressive die stamping is ideal for long runs, because the dies last a long time without becoming damaged, and the process is highly repeatable. Each step in the process performs a different cut, bend, or punching operation on the metal, thus gradually achieving the desired end-product shape and design. It is also a faster process with a limited amount of wasted scrap.
Transfer Die Stamping
Transfer die stamping is similar to progressive die stamping, but the part is separated from the metal trip early on in the process and is transferred from one stamping station to the next by another mechanical transport system, such as a conveyor belt. This process is usually used on larger parts that may need to be transferred to different presses.
Four-Slide Stamping
Four-slide stamping is also called multi-slide or four-way stamping. This technique is best-suited for crafting complex components that have numerous bends or twists. It uses four sliding tools, instead of one vertical slide, to shape the workpiece through multiple deformations. Two slides, or rams, strike the workpiece horizontally to shape it, and no dies are used. Multi-slide stamping can also have more than four moving slides.
Four-slide stamping is a very versatile type of stamping, such as in electronics hardware, as different tools can be attached to each slide. It also has a relatively low cost, and production is fast.
Fine Blanking
Fine blanking, also known as fine-edge blanking, is valuable for providing high accuracy and smooth edges. Usually done on a hydraulic or mechanical press, or by a combination of the two, fine blanking operations consist of three distinct movements:
Clamping of the workpiece or work material in place
Performance of the blanking operation
Ejection of the finished part
Fine blanking presses operate at higher pressures than those used in conventional stamping operations, hence tools and machinery need to be designed with these higher operating pressures in mind.
The edges that are produced from fine blanking avoid fractures as produced with conventional tooling and surface flatness can exceed that available from other stamping methods. Since it is a cold extrusion technique, fine blanking is a single-step process, reducing the overall costs of fabrication.
Types of Stamping Presses
The three common types of stamping presses include mechanical, hydraulic, and mechanical servo technologies. Usually, presses are linked to an automatic feeder that sends sheet metal through the press either in coil or blank form.
Mechanical
Mechanical presses use a motor connected to a mechanical flywheel to transfer and store energy. Their punches can range in size from 5mm to 500mm, depending on the particular press. Mechanical pressing speed also varies, usually falling between the range of twenty and 1,500 strokes per minute, but they tend to be faster than hydraulic presses. These presses can be found in an array of sizes that stretch from twenty to 6,000 tons. They are well-suited for creating shallower and simpler parts from coils of sheet metal. They’re usually used for progressive and transfer stamping with large production runs.
Hydraulic
Hydraulic presses use pressurized hydraulic fluid to apply force to the material, such as in agricultural machinery parts. Hydraulic pistons displace fluid with a force level proportional to the diameter of the piston head, allowing for an advanced degree of control over the amount of pressure, and a more consistent pressure than a mechanical press. Additionally, they feature adjustable stroke and speed capabilities, and can typically deliver full power during any point in the stroke. These presses usually vary in size from twenty to 10,000 tons and offer stroke sizes from about 10mm to 800mm.
Hydraulic presses are usually used for smaller production runs to create more complicated and deeper stampings than mechanical presses, such as car spare parts. They allow for more flexibility because of the adjustable stroke length and controlled pressure.
Mechanical Servo
Mechanical servo presses use high capacity motors instead of flywheels. They are used to create more complicated stampings at a faster speed than hydraulic presses. The stroke, slide position and motion, and the speed are controlled and programmable. They are powered by either a link-assisted drive system or a direct drive system. These presses are the most expensive of the three types discussed.
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