Why powdercoat? Because the...
Why powdercoat? Because the process is simple, you can get practically any olor you want and powdercoating is more durable and easier to clean than paint.
Powdercoating is the process of applying a dry pigmented powder to a surface via air pressure and a light electrostatic charge and bonding that powder to said surface with the aid of heat to melt the powder so that it creates a hard, durable shell.
But you don't really care about that, and to be honest, neither do we. At Circle Track, we're all about helping you have success on the racetrack, not having science class. So let's get to the point.
Powdercoating is an excellent technology when it comes to protecting metal. And that is why it has become quite popular with both racers and chassis builders, who will have a new racing chassis sent out for powdercoating instead of paint. Compared to a traditional paintjob, powdercoat is stronger, more durable, resistant to solvents, is easier to clean, and just plain looks good longer. In the world of stock car racing where the chassis is constantly being blasted by sand and grit blown up off the track, having your chassis powdercoated-if you can afford it-is almost a no-brainer.
But we all know that race teams rarely go more than a week without changing chassis components. Whether replacing damaged lower control arms or updating the car with newer parts, the race car is always evolving. This often means that by midseason a team has many new parts on the car that it either didn't have time to send out for a matching powdercoat or just didn't bother and now have several components with poorly matching paint.
The good news is powdercoating smaller parts is actually a very simple and easy process. The big guys have lots of money invested in powdercoating equipment and wall-in ovens which are necessary if you are going to be coating entire chassis, but for smaller components it's overkill.
This is the powder gun. In...
This is the powder gun. In order to work best, the air pressure should be regulated between 5 and 10 psi. Also, moisture is the enemy of powder, so in order to make sure the air stays dry, it is a good idea to add a moisture filter between the air line and the gun (the black bulb you see here).
Clumps of powder can cause...
Clumps of powder can cause the gun to "surge" or blow powder unevenly. Because of this, you should strain the powder before use if you notice any clumps.
The process of powdercoating...
The process of powdercoating doesn't require specific strokes like painting. Instead, the electrical charge applied to the piece being coated attracts the powder. To create a cloud of powder all around the part and promote uniform adhesion, you can add a deflector like this to help diffuse the powder as it exits the gun.
There are several different powdercoating options out there, but Eastwood has some of the most affordable and easy-to-use kits for the race team that wants to do some of its own powdercoating work. For this article, we got our grubby mitts on Eastwood's newest offering, the Dual Voltage HotCoat Powder Gun (PN 11676).
This newest gun adds a feature which allows you to choose between 15kv for smaller parts and 25kv for big jobs. The electricity ratings are used because most powdercoating systems, including this one, use electricity to put a small electric charge on the metal components being coated. This causes the powder to be attracted to the metal, resulting in a consistent coating even in hard to reach areas.
In addition to the gun, Eastwood also offers a multitude of different colors, including clear and chrome. All you need is an air compressor with a regulator capable of maintaining 5 to 10 psi and an oven for baking the powder onto the material after it has been applied.
As you will see from the included photos, we experimented on several different components and largely had good success. But, just like painting, the end result from any powdercoating project greatly depends on the prep work you put in. All components must be stripped to their metal, have any rust removed, and be clean of oils or other contaminants.
The process requires heating the powder to between 375 and 450 degrees (depending on the type) in order to get it to "flow out" or go into a liquid state, any parts you wish to powdercoat can't have rubber or other heat-sensitive materials on them.
Still, if you can lay your hands on an old electric oven at a yard sale or flea market, you will have exactly what you need to powdercoat your own suspension components, brackets, pulleys, or just about anything else you can think of. It only requires a little more time than fogging the part with a rattle-can paintjob, and the finished surface will be much easier to clean, which will save you time in the long run.
In this article, we'll hit most of the important points for powdercoating your own components, but if you want more information, Eastwood has an excellent resource available in the Powdercoater's Handbook. The book is a quick read and presents all the information in an easy-to-understand manner.
1 The first step in the process...
1 The first step in the process actually has nothing to do with the powdercoating gun. The part to be coated must be completely stripped of all paint, rust, previous powdercoat, and other contaminants. The silica from sand has proven to be dangerous if inhaled when sandblasting, so I'm using one of Eastwood's soda blasters to strip the parts down to bare metal. Plus, clean up is easy. The abrasive is essentially baking soda, so the next time it rains the stuff just melts away.
2 After the components are...
2 After the components are stripped, there may still be oils and other residues that can weaken the powder's bond. You can remove this with a good oil remover like Pre painter's prep and then wipe it down with a lint-free cloth. If the piece is very oily, you may have better results by baking it after stripping the paint to evaporate the oils that can actually seep into the pores of the metal.
3 Like most racers, I don't...
3 Like most racers, I don't have easy access to a paint booth. The solution I came up with was to do my powdercoating work in a bare area in the center of my shop. Unless you have a fan creating a steady breeze, the powder settles nearby and cleanup is no more involved than simply sweeping up afterward. Here, you can see the mist of red powder as I coat a strut brace for a Mini Stock Toyota. Also notice the clip with the black cord which is used to energize the piece to be coated.
4 A properly coated piece...
4 A properly coated piece will have a dull look to it. Before baking, look everything over closely to make sure there aren't bare or thin spots where you can see the metal.
5 The selector on the control...
5 The selector on the control box lets you choose between 15 and 25 kv. The higher setting is for bigger jobs like valve covers, intakes, and wheels.
6 If you can score a used...
6 If you can score a used oven on the cheap then great, but I often use this small toaster oven that I purchased for less than $40. Just never use a gas oven, and don't use an oven you normally cook in. Preheat the oven to 400 degrees, insert the coated part and watch for the powder to "flow out" or melt and begin to look shiny. After all the powder all over the part has flowed out, allow it to cure at 400 for an additional 20 minutes and then cool slowly.
7 A look at two finished strut...
7 A look at two finished strut supports in different colors. Once the part is cool to the touch, it's ready to be installed on your race car.
8 You can also use heat-resistant...
8 You can also use heat-resistant masking tape and plain old aluminum foil to mask off areas you don't want coated. There's no reason you would ever want to coat half of a valvecover in real life, but in this example I wanted to try Eastwood's two-stage chrome coating and masked off half the valvecover so that you can see a before and after.
9 The first coat is a chrome-before...
9 The first coat is a chrome-before it is baked the powder looks anything but.
10 Here's how it looks after...
10 Here's how it looks after curing.
11 The second layer is a clearcoat...
11 The second layer is a clearcoat powder. Again, looks before curing can be deceiving. By the way, you don't want to over-bake clear powders, the instructions recommen375 degrees for 20 minutes after the powder flows out.
12 The finished product. Not...
12 The finished product. Not only does it look worlds better than before, but it should stay looking that way despite engine heat and racing abuse.
13 There will also be instances...
13 There will also be instances when you want to keep the powder from building up in bolt holes and other areas. You can use either aluminum foil or high-temperture silicone plugs as you see here for this pulley.
14 Here, you can see the results...
14 Here, you can see the results of masking off the areas you don't want coated as well as a mistake on my part. You can see the rough patch on the pulley where I didn't completely prep the metal beforehand. Because it goes on thicker than paint, powdercoat will hide some blemishes that paint won't, but it also won't work miracles and cover shoddy prep work like you see here.