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Powder coat vs Paint

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Whitephrog

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When do you powder coat black parts instead of paint? Which parts? Why?
 
Powder coat is tougher than paint and resists more chemicals. Powder coat is ecologically freiendly. Powder coat costs more than paint. You make the choice. If I had unlimited $$$ I would Powder coat most everything.
 
i just bought the powder coating starter kit from eastwood this weekend. i have many parts i want to coat but need the used oven first. i like the idea of powder coating over spray for the durability. powder is supposed to be 10 times the durability of spray paint. all of my covers, pedals, supports, bolt heads ... almost anything that is small enough for the oven and otherwise spray painted will now be powder coated.
 
The above statements regarding toughness are true but ONLY when the panel/part is properly prepped. It also doesn't apply to parts subject to impact damage. For example, a powder painted smooth part of a frame subject to impacts from road debris will not hold up as well as a wet-painting. Powder coat will also chip under fasteners unless the part is VERY well prepared. In general though, under-hood items that aren't subject to impact and that can be taken apart for prepping can have gorgeous results with powder paint.

Again, to me its a question of how much preparation you're willing to do and whether or not the part is subject to impact damage or has high-torque fasteners in it.
 
I have been powdercoating almost everything on Spridgets for a few years now.
I have the Eastwood $100 kit and an oven I picked up in the trash.
I do certain screws and bolts, brackets, most suspession parts, And things like the shifter tin gets powdercoated as close to the car color and then I paint over it. This way when, not if, it chips, it doesn't look that bad with the powdercoat under the paint. I even use off white powder for many parts on an OEW car since it's a dead match.
 
it's also nice in the fact that once the powder coat is cured from the oven, it's ready. i agree that chipping will eventually occur and initial prep is critical, but given the fact that spray paint is so easily scratched, i prefer to go the powder route.
 
Thanks to all for the response. Two things.

I guess I need a good definition for "properly prepping" as this appears critical.

Could the off white be used on an OEW Bugeye stainless fuel cap?
 
as i understand proper prep, it would be to make sure all old paint is removed (blasting preferred) and then the entire piece cleaned with acetone or paint prep solution. the part should be handled with nylon gloves to prevent oils from your hands and then the area where you apply the powder should be fairly dry and clean.
 
As with all painting, no oils or grease should be on the surface. Powder paint benefits from a rougher surface than wet paints as the roughness provides an anchor. For DIY, sandblasting is preferred when possible.
 
Just an observation I had the few times I have powdercoated and this may not be true on all things. When you bake the parts in the oven sometimes more "stuff" assumably oil comes out of the metal no matter how much you have cleaned it beforehand. This happened to the first set of wheels I powdercoated and you could see darker areas under the powder. Since then when I powdercoat stuff I sandblast it first, then bake it in the oven for a few minutes, allow to cool some then clean it with acetone. This "preheat" gets rid of some more of the oils and such. Then apply powder and bake as normal.

Brandon
 
good advice as this is also reenforced by the instructions i have for my kit. especially porous materials such as cast iron.
 
I made some automotive brackets and had them powder painted at work many years ago. I laid out my work using Dykem (a layout/marker fluid) and didn't get all the blue dye off the surfaces. It bubbled right to the top of the off-white powder coating. It looked gross.

Solvent cleaning and prep just like you do for wet-painted parts is required for good powder paint results. The additional pre-baking mentioned above should help. However, you may need to wipe the surfaces down a second time with prep-sol after pre-baking in case you floated oil to the surface but the heat wasn't enough to evaporate it.
 
again solid advice backed up by the information i have. there is obviously pros and cons for powder vs rattle cans. i will not be able to powder certain things, but my experience with RCs has been disappointing both in durability and finish.
 
Has anyone tried the POR 15 line of paints? I am using their system on the suspension parts due to the reccomendation of people on a UK list. It is an American made product and seems to be just as tough as any powder coating I have ever used. It also is specifically for rust proofing too. I live in CA so rust is not an issue but it is easy to use and is fully cured, not just dry in 18 hours. Anyway I am very happy with it.
One drawback to powder coating and it might not matter here is the inability to see cracks in the coated metal. The coating is so flexible that it won't crack when the part cracks. For this reason the FAA discourages it's use on airframes, and I don't use it on motorcycle frames for racing bikes. It also is had to keep the coating from getting too thick and looking"funny".
 
I had problems with POR-15 and solvent pop. But I've also had some success with it too. Lately, I've used "rust encapsulator" from Eastwood.
 
good points and something i was looking at recently with my a-arms. one of the fulcrum bushings had an obvious broken weld and had it been painted or PC'd with enough stuff it would have been covered up. i have seen samples at eastwood and when the coating is done right, it's not too thick and doesn't look like it would cover a crack or weld. i did ask questions about the eastwood video because it loked like they piled on the powder when they painted the wheel hub. i have no professional sprayer so i am depending, in part, on the PC to help out with parts like the suspension.
 
I've used POR. I have a love/hate relationship with it. People are easily encouraged to use it based on the advertising literature that makes it sound easy to use. To adhere properly, POR requires a significant amount of prep work and is a lengthy (read multiple day) process. On parts with lots of smooth, flat surfaces (like frames) it is really important to roughen up the surface so POR will stick. Without something to lock onto the POR will peel off in lovely sheets. Their acid etch step (Metal Ready) is helpful... but its real benefit comes in combination with a slightly rough surface like sandblasting produces. I have found however, that on porous parts (like cast iron) the inherent roughness and porosity of the part makes POR stick very well.

Remember that POR is UV sensitive. I put Eastwood's chassis black paint over POR that will be exposed to sunlight.

EDIT: Regarding Trevor's comments on solvent pop... it's very easy for this to happen and is related to my comment about multiple days. You have to get the right "feel" on the surface of the curing first coat before you apply the second coat. If it's not cured enough, you trap solvents and get the pop. If it's too cured, the second coat won't adhere well. SO... most the prep work needs to be done on the first day (or more) and the actual paint application started early on the second day. During the second day you have to babysit the POR so you apply coats at just the right time. Rust Encapsulator is much easier to use.
 
My powder coater cleans the parts with spray brake cleaner before they get coated. Works like a charm as a degreaser.
But, all this is after they have been sandblasted.
Jeff
 
About any high evaporative rate solvent will work... but that is about the best "Quick-n-Dirty" way to decontaminate a "raw" surface. He's to be commended!
 
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