Crosslink Powder Coating's...
Crosslink Powder Coating's Scott Tolar puts the finishing touches on a new Legends Car chassis for a customer. The white powder is actually a clear coat that will provide a beautiful depth to the maroon powdercoat underneath once it has been heated and cured.
Powdercoating isn't a new process. It has, in fact, been around for quite a while. But it has become much more popular in the last decade as the availability of powdercoating services has gone up while the costs have gone down.
The benefits of powdercoating are numerous and vary depending on your application. When it comes to racing, it's not necessarily better than a good old-fashioned coat of paint in every instance, but there are times when it is preferable. Metal that has been properly powdercoated will not rust and is much more resistant to chipping or scratching than paint. That's because the powder that is applied is actually a plastic that forms a protective sheath around the material and can flex in the event of an impact instead of chip or crack. It also is more resistant to chemicals such as cleaners and even race fuel, which can eat away paint.
The difference between powdercoat and paint is the material itself. Instead of a liquid that is sprayed in place, powdercoat consists of finely ground plastic particles that contain a color pigment. Although the plastic particles are sprayed through a gun, they aren't sprayed directly onto the material to coat like paint. The applicator gun charges the particles as they exit, and the powder is sprayed as a mist into the air. The material to be coated is grounded so the fog of particles sprayed into the air is attracted to it.
Once the material is properly coated, the ground is removed and the material is placed into an oven that has been preheated to around 450 degrees F. Once the material to be coated has reached the oven's temperature, the powder will "fluidize" or begin to melt and bond together. After all the powder has fluidized, the operator will leave the piece in the oven for approximately 20 minutes to allow the powder to cure. Once it has been removed from the oven and allowed to cool, the powder will be formed into a skin around the material that's slightly thicker than a coat of paint. As soon as it is cool to the touch, it is ready to go. There is no sanding, polishing, or other such after-process prep that is common with paint.
Pro Tips For their powdercoating needs, many race teams find the best resource is a local dedicated powdercoating shop. Most shops routinely do everything from industrial pieces to iron railings. Powdercoating a race car chassis isn't outside the abilities of your average shop, but there are a few special considerations you should be aware of.
Powdercoating race car chassis...
Powdercoating race car chassis is very popular because the coating is much tougher than traditional paint, but it is outside the scope of most race shops because it requires a large oven such as this one.
Crosslink Powder Coating is located in Mooresville, North Carolina. Facility owner Scott Tolar says that while his company can and will powdercoat just about anything, his proximity to so many NASCAR Nextel Cup shops means a large part of his business is racing related. As such, he's developed an understanding of what racers are looking for to help them get the most out of the pieces they have powdercoated.
"The first thing every race team wants to know is how quickly they can get their chassis back," Tolar says with a grin. "As soon as they get a chassis done they are ready to start bolting parts together and don't want to waste a lot of time with their chassis in the shop, so we try to make sure we can get it back to them as quickly as possible. If the chassis you bring in doesn't require an extreme amount of prep work before we can coat it, we can usually turn it around in a week. Whenever you are working with a powdercoater, they should be able to work with you to get your stuff back [to you] as quickly as possible."
Chassis are one of the most popular racing components to be coated. That's because it takes so much abuse on the track and the powdercoat will protect so much better against chipping than paint. Tolar says some racers are hesitant to powdercoat a chassis because the thicker coating weighs slightly more than paint. (A proper powdercoat is 3-5 mm thick.) But, he says that after about three coats of paint, which often happens from occasionally repainting scarred areas, the total weight equals out.
Before bringing in your chassis, there are a few basic steps you can take to both speed up the process and ensure you will receive the best job possible. Because the powder is baked at approximately 400 degrees, anything that can be damaged by extreme heat must be removed. This includes all rubber grommets and bearings. Any marks left over from the fabrication process should also be removed beforehand because, Tolar says, they will show through lighter powdercoat colors. You should, however, leave the masking chores to the powdercoater. Because of the heat, a special heat-resistant tape is used to mask areas that aren't to be coated. Unlike duct tape or even standard masking tape, it won't leave a gummy residue when removed from the oven. Finally, it's a good idea to go over the chassis and hit any spots that have been roughed up with a grinder or smooth out any rough welds with finer-grit sandpaper. Tolar says that if you powdercoat over rough metal, it is possible to get thin areas in the powdercoat that won't protect the metal as it should.
Fuel cans are a popular option...
Fuel cans are a popular option for powdercoating because the material is impervious to race fuel, which will eat through paint.
Once the chassis or any other piece is received by the powdercoater, they should give it another once-over for anything you might have missed and strip the metal of any contaminants, such as oils. This can be done by spraying it with a cleaning solution or even baking it at very high temps to cook out any contaminants. However, this requires the piece to be cooked at up to 750 degrees, so this can only be done with steel pieces that can withstand the high temps without metallurgy problems. Baking the piece beforehand obviously requires more time and will cost you more, so a quality powdercoater should only recommend this if it is absolutely necessary. If the chassis is painted or already has a powdercoat that must be removed, it should be stripped in an abrasive blaster. Tolar recommends using a finer blast material than sand because the sand can etch the metal, which might show through the final powdercoat. Once the material is stripped and cleaned, the powdercoater may put the piece in the oven once again to burn off any remaining fluids and mask any areas that should not be coated. This includes any threaded holes or areas where tight clearances are required. If your powdercoater isn't familiar with race car chassis or components, make sure you are very specific with him or her about what areas should not be coated. It's much easier to mask an area beforehand than to strip the powdercoat later.
When it comes to the color you choose, your options are nearly as limitless as they are with traditional paint. There are flats and glosses, metal flakes, simulated chrome, and even clear coats. It's easy to allow things to get out of hand, but Tolar recommends sticking with one of your basic colors. Dove Gray is popular for a reason-after a race, it's easy to spot fluid leaks or cracks. Whatever you choose, Tolar says having a color that can be easily matched with a rattle can of spray paint is useful because it allows you to easily cover areas where the powdercoat has either been damaged or stripped away for welding or other repair work.
Besides steel, modern powdercoating technology can work with aluminum, brass, some plastics, magnesium, and even tungsten. This has opened up the doors for many race teams in creative ways. Besides the chassis, Tolar says teams will often have their pit equipment, including jackstands, coated to match their sponsor's colors. The powdercoat keeps the equipment looking sharp longer. Fuel cans are also a popular option because race fuel won't eat away the powdercoat like it will paint. If your rule book requires your chassis weights to be white, and you constantly find yourself repainting your lead or tungsten because of the beating it takes going into and coming out of the framerails, consider having them powdercoated. You can even go so far as to coat your suspension springs if you don't want other teams to know the brand or weight of the spring you are running. It won't replace traditional paint in every application, but powdercoating is providing racers more options than ever before.
Here's the finished product....
Here's the finished product. After fluidizing at approximately 450 degrees and curing for an additional 20 to 30 minutes at 375 degrees, the powdercoat will be cured and race ready as soon as the chassis is cool to the touch.
Crosslink recently powdercoated...
Crosslink recently powdercoated an entire car, both chassis and sheetmetal, for a race team that was looking for a more durable option than paint.
Because the material to be...
Because the material to be covered is negatively grounded and the powder particles are positively charged as they leave the gun, the particles are actually attracted to the surface to be coated. This means a complex shape such as a race car chassis and rollcage can often be more evenly coated more quickly by an experienced powdercoater than by the use of a paint gun.
Our Eastwood kit included...
Our Eastwood kit included the powdercoating gun and everything else necessary to get started, including hanging wire, plugs, high-temp masking tape, and several powder options.
The powdercoating process is relatively easy to perform, and the tools required are easy on the wallet. Yes, professional powdercoating shops have a lot of expensive industrial equipment-such as an oven large enough to fit your race car chassis-but by using a smaller household oven and sticking to smaller parts, you can easily do most of your powdercoating yourself.
One of the most popular options for do-it-yourselfers is Eastwood's HotCoat powdercoating system. To get you going as painlessly as possible, Eastwood offers what it calls the Elite HotCoat kit, which not only includes the powdercoating gun, but also just about everything else you need to get to work. The components are invaluable for getting quality results. They include the following: four bottles of standard powder colors, extra empty bottles and lids to facilitate easy color changes, high-temp masking tape, silicone high-temp plugs, a spool of stainless steel wire for hanging parts, and the Beginning Powder Coater's Handbook, among other things. The only thing you need to supply is clean compressed air (you need a steady flow at approximately 10-15 psi) and an oven for curing the powder.
We tested Eastwood's system with a medium-sized toaster oven that we scored at Wal-Mart for less than $50, and the results were quite good. The book included in the kit is quite helpful as it guides you through the entire process, from prepping the parts to cleaning your gun to get the best results. However, you need to use an oven that won't be used for preparing food anytime in the future. As some powders fluidize, they can sometimes release mildly toxic fumes. They aren't a danger to you in the normal powdercoating process, but you don't want to eat any food cooked in that oven.
The first step is to completely...
The first step is to completely clean and strip the piece you will be coating. For complex shapes that create impossible-to-reach areas for a sander, a small media blaster such as this unit from Craftsman works quite well. Just don't blast the metal too hard. Etching will show through the powder.
Oils and other contaminants...
Oils and other contaminants that remain on the part will show through the powder as dark spots. Eastwood offers a product called "Pre Painting Prep," which effectively removes grease, oils, and other contaminants from the metal's surface. Just spray it on liberally and wipe. Of course, from this step forward you should be wearing latex or nitrile gloves to keep from contaminating the piece with the oils from your skin.
The valve covers I wanted...
The valve covers I wanted to coat didn't fit into the toaster oven (they will wait until I score a used oven), so I used several small parts from a Pure Stock engine for testing. Here, one-coat gloss red is being applied to a pulley.
Here's the part ready to be...
Here's the part ready to be cooked. Note the silicone plugs used to keep powder out of the bolt holes. One useful trick is to use aluminum foil as a mask to keep powder out of the belt groove.
The gray powder on this fan...
The gray powder on this fan spacer is actually a one-coat chrome.
The finished products turned...
The finished products turned out surprisingly well for a first-timer. Although the Elite HotCoat kit from Eastwood can be had for less than $200, the results are very professional in both appearance and quality.
Crosslink Powder Coating - 704/660-1864
Eastwood - 800/343-9353