Posted by on 11 July 2017
Before we get this train moving, we should probably define what exactly a special effect coating is. The list is pretty long, as essentially everything that is not a solid color can fit into this category. The definition of a special effect can also differ between powder manufacturers and job shops. Some of you may consider low glosses and matte finishes as special effects; others may not. Most companies will say that metallics fall under the special effects class – however, we have a whole guide dedicated to metallicsand will not be focusing on them in this guide.
We will cover why we use special effects, what their chemistry is, how to use them, how they can go wrong, and we'll give you some top tips for how to use these particular coatings best. Specifically, we will cover wrinkles, translucents, dormants, river veins, multi-components and fine textures.
Why do we use special effects?
Most of the time, what it comes down to is what your customer wants aesthetically. Perhaps they need a rusty looking finish, or a rough texture, or an extra something to make the part stand out from the crowd. It is usually driven by the customer needing a specific aesthetic, or designers aiming for particular looks. However, the need for a special effect could also come from the need to hide a substrate surface that doesn’t look good. This is the main functional reason for using them.
What can affect a coating like this?
Typically, what kind of special effect you use is not affected by what the substrate itself is. However, pretreatment systems can affect how well a coating applies and cures. Galvanized, especially hot dip galvanized, the substrate can cause issues with outgassing – which we will talk more about in the next guide, Appearance Issues: When Jobs Go Wrong. A wrinkle effect can be botched by an improperly cleaned surface. Translucents need a clean, even substrate, with a uniform appearance, otherwise results in the final coat will vary.
Then there is the application process itself. Like with any coating, if it is not applied correctly, it will likely not cure properly, resulting in, if not an outright reject, an unattractive finish. Some powders will even change in color or pigmentation depending on how thick the film is.
Let’s get into these issues in more depth, starting with…
Wrinkles
Most commonly, wrinkles are typically a polyester or urethane chemistry, occasionally an epoxy. Check out our blog on the different types of powder chemistries and the advantages of each to fully understand the best applications for urethane powders.
Now, wrinkles can be a tricky coating to get right. So as we always say, if you’re new to working with urethanes, this is probably a coating you want to test out on some sample panels before moving on to coat the part. So let’s break down where things can go wrong with this special effect. First up, the application and substrate! If your surface is not consistent in cleanliness and texture, the wrinkle effect will look different; some spots may work well, and others not so well – if at all. Secondly, the oven. If the temperature varies, say, by a few degrees in one corner, then you are going to get varied results in your finish. Check your oven settings and test out a few panels to ensure everything is in tip-top shape. Urethane wrinkles can also be sensitive to heavy film build on the edges – so be mindful of that when applying them. When wrinkles are done right, they look amazing. Get it wrong, though, and you have a doozy of a reject to deal with.
Why use wrinkles?
Wrinkles offer a very specific look. Smooth, classy and sophisticated, wrinkles are a comparatively mild special effect that can add real depth to a color and are pretty good at hiding the substrate. Not only are they a great visual effect but they also have decent weathering, good hardness, corrosion resistance, chemical resistance, and they are a great special effect for covering up surface imperfections.
Top Tip: In general, urethane based coatings are good for chemical resistance. They are durable too. But, they do bring a lot of process issues with them. Like wrinkles themselves, if urethanes aren’t applied right, they go very, very wrong.
How do I apply wrinkles?
The key to a good wrinkle is preparation. Have a good pre-treatment system in place. No matter if you shot blast or use chemical pretreat, keep it consistent across the board. Clean all contaminants, especially oil, from the part and ensure the pretreat is applied evenly as any dirt or contaminants can interfere with how the wrinkles form.
Next, depending on whether you use a batch oven or automatic system, you need to be sure that it is a conventional fire oven. You need to be able to ramp up the temperature quickly at the start of the cure cycle to ensure consistent wrinkling in the coating. In our general experience working with wrinkles in an infrared oven can be extremely tricky and is best avoided!
As for the actual application, it applies like any other powder. The trick is to settle on a film thickness that achieves the effect you and your customer want, as a thinner film may not wrinkle to the same degree as a thicker film. Be certain to always refer to the Technical Data Sheet for accurate thicknesses and cure times.
Translucents
Translucent powders offer a unique finish in a variety of colors. As the name suggests, translucents cover the substrate, provide color (and they can even have metallic added) to the part, but allow a hint of the substrate to show through. Many customers love that effect of a beautiful hue with the suggestion of natural metal showing through and built in.
It is pretty common to find translucents in either polyester or urethane chemistries. With the latter, note the pitfalls we listed above. Polyester tends to be more forgiving than urethanes in that department, though it is somewhat limited in smoothness and exterior durability. At the line level, polyesters are easier to deal with, and urethanes, while trickier, can offer a better overall flow and appearance.
A big pitfall with translucents is that it is very easy to have uneven pigmentation on the substrate, especially if it is an irregular shape – like a table leg. There can be visible differences with as little as half-millimeter variations in film thickness. Due to their nature, these special effect coatings will also allow the nature of the substrate beneath to show through. This can be the main reason why a translucent is used. If it isn’t, laying down a white or silver basecoat is a step you can take – this is especially useful if the surface is not uniform in coloring.
Why use translucents?
As we said above, sometimes designers and customers want the metal beneath to show through, just with a bit of pizzazz on top. Translucents are the best way to achieve such a look. Other times, translucents offer an impressive brightness as compared to other coatings. This special effect also works extremely well on stainless steel, and due to the high percentage of resin in them, they apply pretty well.
How do I apply translucents?
Any marks, scuffs, blemishes, and discolorations on the substrate will show through a translucent coating. If a pre-treatment does not remove them, then you will need to lay down a base coat of some kind. IFS bright chrome is often used to cover a less than perfect substrate and lay down a bright, even base, before applying the translucent coating on top. This creates a really bright, beautiful finish.
Beyond that, what getting a great result using translucents comes down to is applying the powder evenly to the surface. Keep the gun steady, watch your gun to surface distance, and time how long you spray each section.
Dormants
Dormants have grown in popularity over the last few years and are bright, almost candy effects but with more depth, brilliance and shine. Dormant special effects are a two-coat system, as a base coat and top coat is applied and baked separately. The base coat, which typically has metallic pigment in it, has a color that will transfer up into the clear top coat upon curing of the second coat. So it’s the top coat, which is actually clear, that really draws the dormant color out and brings the dormant to life. For example, a red will appear as a dull pink before the top coat is added This also means that you need to make sure you use the base coat and top coat designed to work together, otherwise you risk all sorts of problems.
The top coat is a clear powder, which is great news as that means they are resin rich. So when purchasing formant effects make sure you get the base color coat and a clear that is designed to give the dormant effect and work together. As dormants are a two coat system, check out our blog and top tips for applying two coats!
Why do we use dormants?
While needing a top coat means adding time onto a job, dormants are wonderfully bright colors with more depth and sheen to them. Bicycles are one product that has really utilized dormants in recent years – so imagine that deep, intense color on the frame and you have a good idea of what they look like. Dormant systems also transfer color much more consistently than translucents and are more forgiving than the latter when it comes to film builds and uniform pigmentation. The use of a top coat also offers additional weathering protection and corrosion resistance.
How do I apply dormants?
It is pretty simple. You lay down a base coat – your color – and bake. Then you lay down your top coat, and bake. Easy as that.
Top Tip: Watch out for back ionization when applying the clear! Use a recoat setting and follow our tips for reducing back ionization or KV rejection. Another thing to consider is where the substrate will be located. Indoors, or outside? Check with your powder manufacturer what chemistry their dormant powder is available in and whether it is suitable for the end use.
River Vein
A river vein is a particularly unique effect. Both IFS and Polychem have a huge range of river veins available in a wide range of colors. It’s definitely worth checking out what they look like with one of our color cards – they’re really popular but are best seen in the flesh (as it were) – pictures don’t do them justice.
Usually, river veins come in polyester technology, though they are available in other chemistries such as hybrids and epoxies too. It is easy for appearance issues to crop up with this special effect. Paying close attention to your film thickness and what the TDS calls for will help here. If it requires three to four millimeters, you really want to be in that range.
Film build really is absolutely key when it comes to applying river veins. Due to the nature of the effect, spray it too thin, then in the “valleys” of the special effect, you can actually see the substrate showing though – not the look we are going for. Consistency is key.
Consistency and film build also affect how the veins themselves appear, especially if you are doing a batch of, for example, tables for a customer. You want uniformity across the line. If your film is thicker on some tables and thinner on the others, the deviations will be visible. Not a good outcome.
Top Tip: When it comes to deciding between hybrid, polyester, or epoxy chemistry for river vein powders, knowing where the coated end product will be situated will help. Hybrids offer more resistance than polyesters, however, hybrids will chalk if placed outside. Cross reference what your customer needs with what powders you use.
Why do we use river veins?
Aesthetically, they offer an interesting look. Plus, if a surface looks….shall we say, like an ugly duckling, river veins can bring out the transformation into a beautiful swan? Okay, that was a metaphor that reached a little far, but you get the picture.
How do I apply river veins?
Generally, river veins are applied like any other powder – stick to the guidelines and mind the information on the TDS. Pretreat, apply, bake, and top coat if necessary. Ta-da! And remember, watch your consistency and film build at every step!
Top Tip: If you are reclaiming these products, you want to be sure to keep a high percentage of virgin in the reclaim, otherwise you might start to see some shifts.
Multi-Components
How to describe multi-components? Seeing is believing, but many of our customers are simply amazed that such a beautiful effect can be created in a single coat. Gets OEM free panels from Polychem to check out some awesome multi-component looks. Trust us – pictures simply don’t do them justice. Given the versatility of multi-components, it is easier to say that what chemistry you use depends on where the coated end product will be used. For example, if the customer needs good weathering, then a super durable could be a great option. Now, due to the nature of this particular special effect, extra attention must be paid during application. We have said consistency is important a lot in this guide…and we will say it again! Be consistent with your gun-to-part distance! It really does make a huge difference.
Again, if you are reclaiming this powder, you want to be sure that your virgin to reclaim is very consistent and higher on the percentage of virgin going back into the reclaim. Good fluidization is also important for multi-components.
Top Tip: When laying out the outlines for a job involving multi-components, it is important to set a standard for what the finish will look like. Setting this standard, working out how much leeway you have for the appearance of the final product, will save you some pain – especially if you have a sample panel to show the customer.
Why do we use multi-components?
They offer a really unique look to a part and can also offer great hiding. There isn’t much more to say than that!
How do I apply multi-components?
Generally speaking, multi-components, apply like any other powder. However good fluidization is really important. Box feed systems can struggle with these effects – bear that in mind. Good control of your application equipment is also important. Ensuring you use the same KV and micro amp settings every time and the same gun to part distance is important – consistency is key. You will get two very different results if you hold the gun at a different distance to the part each time, Also, if you are reclaiming, be sure your virgin to reclaim mix is very consistent with a higher percentage of virgin going back into the reclaim.
Fine Textures
Job shops, designers, and suppliers will all have their own variations on what they define as a fine texture. At IFS Coatings we consider fine sand and grit to be a fine texture. Sometimes, a fine texture can be so faint that it is hardly visible. At the base level, fine textures are powders with a texture added in alongside the pigmentation. They’re great for hiding substrate defects and also for achieving a more matte look.
Because of this added texture, one thing to be noted is that the more texture you build up in a film, the lower the gloss effect will become. Another factor to keep in mind is that textures, fine or heavy, can cause a fair bit of wear and tear on your equipment. Reclaiming equipment, fluidizing hoppers, hoses, and the internals of spray guns can all be affected. If you are spraying textures frequently, dedicated equipment might be in order – you do not want a texture powder to contaminate another.
Why do we use fine textures?
Let’s be honest, okay? Sometimes fine textures are used to cover up cruddy welds and surfaces. It can be for a specific look a designer wants, of course, and heavy textures are often used to create anti-skid surfaces – like RV steps. But, textures are often used as a concealer.
How do I apply fine textures?
Fine textures are somewhat more forgiving than the other special effects we have covered. In general, so long as you are consistent in film thickness, it applies and cures like any other coating. Still, a good rule of thumb is not to go too heavy or too light. Keep it just right.
Top Tip: One final time…Consistency. Is. Key! Texture builds up quicker than you think, and it will be rather obvious if the film is not uniform in thickness. Mind your gun distance. Clear up exactly what is required of the product with the customer, too, and figure out how much leeway you have concerning the look of the finish. Not every texture will come out looking exactly the same, and it is important that customers know this – we would even suggest a full agreement that the customer signs off on before you start the job. Good practice no matter what the effect.
To Top It All Off…
We have covered special effects including wrinkles, translucents, river veins, dormants, multi-components and fine textures. They are a versatile category of coatings that offer unique and interesting aesthetics and come with their own pros and cons. While some are trickier to apply than others, learning the ins and outs of them in a step in the right direction to mastering their techniques. The more you learn, the more you can offer your customers.
Questions? Drop us a line at coatingsinfo@ifscoatings.com!
FAQs
What is the special effect of powder coating? ›
Process Powder Coating Special Effects
A process special effect is a special powder coated finish that can only be applied with multiple powder applications and curing steps. This includes candy colors and two-tone finishes.
Powder coating is a dry powder applied to a charged surface, creating a thicker coating in one application more than a single coat of paint. An electrostatic charge holds the coating onto the surface, which remains in place after curing the object.
How do you paint something that is powder coated? ›Normally, powder coating has a slick surface which does not allow paint to stick. Sanding it down carefully will enable you to paint on it effectively. Wipe down the area you will be painting with an appropriate solvent cleaner. Finally, rinse it down with warm water, then allow it to dry.
How is powder coating applied to metal? ›The powder is sprayed through an electrostatic or cornea gun onto a metal surface that is grounded. The electrical charge given to the powder by the gun is attracted to the grounded surface of the metal. The coating is cured at a specified temperature; cure temperatures vary depending on the coating being applied.
What pressure do you use for powder coating? ›Energy-efficient and cost-effective powder coating withstands up to 6,000-7,000 psi of pressure compared to approximately 1,000 psi with traditional wet paint. This translates to a finished product able to withstand a number of adverse conditions.
Can you apply powder coat with a brush? ›Here are two common methods for painting powder coats: Brushing: Brushing is more time-consuming than spraying, but it yields a high-quality result. Similar to spraying, you should move the brush in a smooth, horizontal direction to apply the paint evenly. We also recommend using a synthetic brush for the best results.
What are the three types of powder coating? ›Some of the most popular types of powder coating include: Epoxy Powder Coatings; Polyester Powder Coatings; Hybrid Powder Coatings.
What is the 7 tank process for powder coating? ›7 Tank Process for Powder Coating on Metal is a seven steps process. These are steps which include Degrease, Rinse, Pickling, Rinse, Phosphating, Rinse, and Passivation. Sometimes we use Activator before Phosphating. We also know it as a Zinc Phosphating Process.
What is the basic knowledge of powder coating? ›Powder coating is a type of coating that is applied as a free-flowing, dry powder. Unlike conventional liquid paint which is delivered via an evaporating solvent, powder coating is typically applied electrostatically and then cured under heat or with ultraviolet light.
What Cannot be powder coated? ›Other materials that can't be powder coated include rubber, plastic, wood and anything else that melts at high temperatures.
Can you paint directly over powder coating? ›
Painting over an existing powder coating is possible and can be helpful when you need to repair a powder coated surface. It is important to consider the extent of damage to the underlying powder coating, the right paint to use to paint over the powder coating, and properly preparing the surface for the liquid coating.
What grit sandpaper for powder coating? ›Start with 120 grit sandpaper and work towards finer grades until the surface is smooth to the touch. Small localized surface defects can be removed using wet sanding techniques with very fine (1000 to 2000 grit) sandpaper. In this case, keeping the repair area as small as possible is best.
Can you powder coat over all metal? ›The powder coating finishes are not only sturdy but flexible as well. It can be used on different surfaces, including metal, concrete, steel, and plastic. It's suitable for both indoor and outdoor applications, and it's one of the most cost-effective finish options.
What is the best way to paint powder coated metal? ›A: Unfortunately, powder coatings are very hard and do not easily allowed other coatings to adhere. A better method for recoating the powder is to lightly sand it with 180 grit sand paper, solvent wipe and then follow with a two-component epoxy primer followed by the enamel of your choice.
Does metal need to be primed before powder coating? ›The process of powder coating calls for attention to detail, and the slightest miscalculation can influence the overall quality of a metal's finish. Using a primer is one way powder coating professionals ensure the long-term performance of your product's powder coating.
What temperature do you powder coat? ›Unlike conventional liquid paints, which require an evaporating solvent for application, powder coating uses electrostatic application methods before being cured under high heat. Most powders require baking at around 350-400 degrees Fahrenheit for 10-20 minutes to fully cure.
How thick is powder coat applied? ›The standard range of powder coating thickness falls around 40 – 80 microns, though specific recommended ranges will differ depending on the powder supplier and the context in which the coating is being applied.
What is the spray distance for powder coating? ›The optimum spray distance for Inconel 625 powders is 8 cm, with a highest average velocity of 781 m/s.
Do you clear coat over powder coat? ›When you apply a clear powder coat over an existing powder coat, the second finish provides an added layer of protection that keeps your material and its first powder coat in pristine condition. For metallic silver or chrome powder coats, we recommend adding a clear coat to protect your finish.
What is the next best thing to powder coating? ›Spray paint can be a viable powder coating alternative.
Atomized paint particles can help you achieve an even layer for your perfect finish. With patience and a few even coats, spray paint can give a smooth finish to your part.
What primer to use over powder coating? ›
Best primer for painting over powder coat? Prime all over with one full coat of Zinsser Bulls Eye 1-2-3 Primer Sealer in accordance with the manufacturer's instructions, allowing a minimum 1 hour drying time (in normal drying conditions).
How many layers of powder coating? ›As a powder coater, you may need to apply two coats for a variety of reasons whether for protective reasons or appearance applying a second coat of powder is important to know how to do well.
What chemical is used in powder coating? ›Resin is always present in powder coating. Epoxy and polyester are the two common types of resin. The coating contains either one of the type. In order to increase the durability and solidify the coating, curing agents are used.
Is powder coating Dry or wet? ›The major distinction is solvent: wet paint contains solvent, but powder coating doesn't. The solvent in wet paint keeps all the other components in suspended liquid form. In contrast, powder coating is applied as a dry powder.
What is 3 stage powder coating? ›During the process, the powder is applied to a substrate's pretreated surface, melted, and then dried and hardened into a protective/decorative coating. There are three stages: surface preparation, coating application, and heat curing.
Can you double coat powder coating? ›The two-coat process involves two coatings applied to the same substrate. The purpose of this method is to enhance the appearance of the finish while protecting it from natural elements.
How many colors are there in powder coating? ›Prismatic Powders has over 6500 finishes available. They offer every kind of color you can imagine including hard-to-find transparent and candy colors. Prismatic finishes are ideal for automotive rims, as well as auto and motorcycle bodies and chopper frames.
What items are most commonly powder coated? ›You'll find powder coatings on home appliances like kitchen mixers and gas ranges, on automotive products like bodies and wheels, and outdoor home features like doors, lamp posts, statues, fences and gates, and even fountains.
What is the ratio of powder to air in powder coating? ›Powder Coating Multiple Coats
For powder to air mix, usually using about a 50% ratio will be ideal.
Why is phosphating done? The process of Phosphate coating is employed for the purpose of pretreatment prior to coating or painting, increasing corrosion protection and improving friction properties of sliding components. Metal coating offers both zinc phosphate and manganese phosphate coating.
Can you mix powders for powder coating? ›
Unlike most liquid paints, mixing two colors don't result in an intermediate color but a blend of individual particles. For example, mixing a red paint and a yellow one of same technology will yield an orange paint. With powder coatings you get a unique speckled finish. So yes, powder coatings can be mixed.
How hard is it to learn powder coating? ›Powder coating has many advantages over traditional liquid coating: It's better for the environment, applies thicker without running, and is easy to style with. Although certain aspects of powder coating can be tricky, it's certainly not difficult, especially for an enterprising soul.
What are the two basics of coating? ›Adhesion: the coating must adhere to the product, meaning there must be a degree of affinity between the ingredient and the product. Coalescence: in case of a liquid, the multiple droplets may merge to form a uniform continuous layer.
Why is my powder coating not sticking to metal? ›On a secondary or top coat if the powder will not stick, the likely cause is voltage (KV) or micro-amps (µA) that is set too high. The first and easiest step is to check the ground and make sure there is an area of clean metal to metal contact. After ensuring that the grounding is sound and the problem persists.
Should steel be galvanized before powder coating? ›The powder coat is applied over hot dip galvanized steel at the galvanizing facility. The first step in producing powder coated galvanized steel is galvanizing.
Will something rust if it is powder coated? ›Powder-coated steel is highly resistant to rust in most cases, so it won't develop unsightly rust patches or leave red streaks on a patio or building facade. However, if it sustains damage, small cracks in the coating may appear, admit moisture and allow rust to form.
Do you sand before powder coating? ›When you're preparing for powder coating, the simple answer is yes; you should always use sandblasting. As touched on above, without sandblasting any type of coating won't properly adhere to the surface of a material.
How do you seal powder coating? ›Using wax to protect exposed surfaces
To protect these surfaces, apply a light coating of a high-grade, non-abrasive vehicle wax. The brand of wax you choose should contain a UV inhibitor or blocker. Don't purchase compound-type waxes, as these waxes have abrasives that could damage the powder coating.
If your customer repaints, recommend using thermosetting acrylic, epoxy, polyester or polyurethane enamels. Although they may not provide the same quality, air drying enamels including aerosol spray can paints will adhere as well.
What causes orange peel in powder coating? ›'Orange peel' can occur when the surface has not been prepared properly before the coating is added. The way that coating is applied can also be a cause, as can the way it is cured after application. Surfaces can be prepared for powder coating with sandblasting or immersion in zinc or phosphate.
Should powder coating scratch easily? ›
The good news is that powder coating is generally very durable and can withstand a lot of wear and tear. In fact, it's often more scratch-resistant than other types of coatings, such as paint. However, it's still possible for powder coating to scratch, particularly if the surface is subjected to a lot of abuse.
What are the bumps in powder coating? ›Pinholes develop from a process called “outgassing.” Pinholes occur during the cure – as the part heats up, gasses that are trapped on or inside the part escape through the powder, causing holes or bubbles in the finish.
Can I do powder coating myself? ›The health hazards associated with powder coating at home are higher than average because the process involves, chemicals, high-voltage electricity, fine powder, chemicals, and heat. Without the right safety training, you can easily endanger yourself and others.
Do you need to sand before powder coating? ›When you're preparing for powder coating, the simple answer is yes; you should always use sandblasting. As touched on above, without sandblasting any type of coating won't properly adhere to the surface of a material.
Does powder coating require sanding? ›all require spot sanding to remove the surface defect and smooth the surrounding area to a feathered edge before repainting. Start with 120 grit sandpaper and work towards finer grades until the surface is smooth to the touch.
How many coats of powder coat can you do? ›As a powder coater, you may need to apply two coats for a variety of reasons whether for protective reasons or appearance applying a second coat of powder is important to know how to do well.
Do you have to primer before powder coating? ›Cleaning and priming surfaces are crucial to the successful outcome of the powder coating process. Powder coating will bond better when the material it's applied to is clean. To ensure surfaces are as prepped as possible, there are a number of steps that can be taken.
What grit is best for powder coating? ›For starters, work on the grit size. The 120-grit paper is fine but it may not be fine enough to avoid lines, especially if you use a motor- driven method. You may need to follow up with a 240-grit to get it smooth. Also, make sure to keep the rotational speed of the device slow enough to control.
What is the best way to prep for powder coating? ›Powder coating prep work
The first and most important step of the process is cleaning. You'll need to clean all the way down to the base metal, which means removing any oils, dirt and paint. The most common methods used to accomplish this include sanding, grinding, media blasting or chemical application.
When you apply a clear powder coat over an existing powder coat, the second finish provides an added layer of protection that keeps your material and its first powder coat in pristine condition. For metallic silver or chrome powder coats, we recommend adding a clear coat to protect your finish.
What kind of primer do you use over powder coat? ›
Best primer for painting over powder coat? Prime all over with one full coat of Zinsser Bulls Eye 1-2-3 Primer Sealer in accordance with the manufacturer's instructions, allowing a minimum 1 hour drying time (in normal drying conditions).
How long to wait after powder coating? ›Powder coated items do not dry like traditional paint.
When the item reaches its target temperature, the powder flows out and generally cured in 15-30 minutes.
No, you can't. Powder coating requires a continuous, high temperature for polymer cross-linking, which a heat gun can't do.
Does powder coating chip easily? ›Once the powder has been applied to a part, it is then cured in an oven. When powder is exposed to high temperatures, it melts down and creates a film. 1. Powder coat is so durable, it can't chip or crack.