Powdercoating Alcoas

[Rivetboy]

Just about to reward my self when this bus of mine runs with Alcoas. I want powder them. Is this a good or bad idea has any one done this?

Cost also but imagine where it is done affects that

Thanks
Joe

[EastCoastCB]

Originally Posted by Rivetboy

Just about to reward my self when this bus of mine runs with Alcoas. I want powder them. Is this a good or bad idea has any one done this?

Cost also but imagine where it is done affects that

Thanks
Joe

If you're gonna do it talk to Marc. He's the powdercoat guy on here.
I like my alcoas shiny or brushed but that's just personal taste.

[magnakansas]

I have concerns about correct bolt tension with powder coated rims. I will give you an example... a propeller is not allowed to have any paint or coatings on the flange or bolt surfaces. There have been cases, more than one, the coating flaked off, fell off, or whatever and the bolts holding the the propeller loosened.

The area under a cylinder on the engine are not allowed any coatings. for the same reason.

the face of the rim where the rim mounts on a flange and the area under the wheel nuts should be bare.

william

[EastCoastCB]

Originally Posted by magnakansas

I have concerns about correct bolt tension with powder coated rims. I will give you an example... a propeller is not allowed to have any paint or coatings on the flange or bolt surfaces. There have been cases, more than one, the coating flaked off, fell off, or whatever and the bolts holding the the propeller loosened.

The area under a cylinder on the engine are not allowed any coatings. for the same reason.

the face of the rim where the rim mounts on a flange and the area under the wheel nuts should be bare.

william

I hear ya. I know here in FL if the wheels are STEEL its actually law that they be powder coated. But not if they're alcoas.

[ennonne]

Google will find a bunch of info about not powder coating forged aluminum wheels because normal powdercoating cures at 400°, above the temperature the wheels are heat treated at. Alcoa/Arconic says not to do it too.

Of course the wheels have already been heat treated, not talking about un heat treated aluminum, and the powdercoat cures in like 10 minutes, so it's really not a big issue. I found a paper that powdercoated what was effectively sheet aluminum (very low thermal inertia) and found very minor changes in properties, like 2%. Well within measurement repeatability in my mind. They saw much larger property differences in the as received aluminum, it was about 20% different than the standards for 6061-T6. Made me feel pretty good about the process.

Paper is titled "Evaluation of the Effects of Powder Coating Cure Temperatures on the Mechanical Properties of Aluminum Alloy Substrates" You can google it and download a pdf copy.

I have a set of used wheels I'm looking into doing. They were originally clear coated. I could strip and polish them, but I'd have to polish them at least yearly to keep them looking good. A parent at the kid's school has a shop that does wheel powdercoating. He says he can powdercoat them with a basecoat of a simulated chrome, then a topcoat of a slightly dull clear. He says they'll look like polished aluminum. He didn't recommend trying to clear coat or powdercoat them after polishing. The surface is too smooth for good adhesion. I'm not sure what he charges, He said polishing is like $70 a wheel around us, and sort of implied that's more expensive than powdercoating.

[Sleddgracer]

a good many years ago I had an elderly sedan delivery - the wheels were rusty and flaking and I was tired of looking at the mess - I did a quick job of scraping and wire brushing to clean them up and sprayed a couple of good coats of red urethane porch and floor paint on them that I had left over from a job - the red wheels looked a bit garish on the light blue vehicle, but they looked a 1000 times better than they did before, and it was done with what I had on hand - the reason I'm bring this up on this thread is that years later those red wheels still had no rust showing and no rock chips - urethane is one of those products that dries to a hard finish yet retains a fair amount of flexibility and I'm guessing that the flexibility is why they resisted rock chips - I can only assume the lack of rust was because of the way I poured the paint to it - thought I'd mention it as a comparatively inexpensive way to clean up those rusty rims with decent lasting power