Powder Coating Wire Wheels

[Magyar]

Has anybody gone through the process of having their wire wheels sandblasted and powder coated? Are there any concerns that I should be aware of, such as heat build-up from the blasting or the 450F from the coating process that could damage the wheel? The wheels are the older style, 48 spoke, painted. I was planing on just cleaning them up and repainting them, but it was suggested that I have them powder coated. Any comments, thoughts, concerns?

Thanks,
Magyar

 

[Patrick67BJ8]

Has anybody gone through the process of having their wire wheels sandblasted and powder coated? Are there any concerns that I should be aware of, such as heat build-up from the blasting or the 450F from the coating process that could damage the wheel? The wheels are the older style, 48 spoke, painted. I was planing on just cleaning them up and repainting them, but it was suggested that I have them powder coated. Any comments, thoughts, concerns?

Thanks,
Magyar

One of the few things I would not powdercoat!
Powdercoating is thicker and the baking process allows the coating to flow into all nooks and crannies and this would probably make replacing broken spokes no longer feasable IMHO.
Patrick

 

[Bruce Bowker]

Agree. Paint them.

 

[BobFrisby]

Are these the original wheels? 48-spoke wire wheels that old are surely going to have problems --- they just don't last forever. I don't know whether 48-spoke wheels are even available new. Seems that everybody goes for 60 (or even 72) spoke wheels when replacing the originals.

Yes the powder coating would interfere with tuning and spoke replacement. But if the wheels are new or freshly rebuilt, they shouldn't need any attention for a very long time.

If your wheels ARE the originals, just paint them and save your money toward new ones.

Bob Frisby
Boise, Idaho

 

[nevets]

My firm has powder coated numerous metal prototype assemblies and the best results are obtained with parts disassembled. Powder coating is considerably thicker than paint, plus masking is not simple due to the heat. Typically we mask threads and all mating surfaces. I would stick with paint.

 

[Magyar]

Thanks All, That was the information I was looking for. I have one painted and it looks great. I just wanted to be sure I was not missing something on the powder coating. Regarding the painting. Would it be prudent to give it a couple of clear coats over the silver/gray color? Would that provide added protection to road chipping or is that just a waist of time and paint?

Thanks again,
Magyar

 

[Rob Glasgow]

Magyar, I painted my wires several years ago and applied three coats of clear over the silver. They still look fresh.

 

[AUSMHLY]

I would question what do I clean or etch the surface with first.
Then, do I use a primer?
The more coats of paint, the higher the chance of it chipping. Too much paint and it chips easily.

 

[Magyar]

Good point. The wheels are in pretty good shape, so the one that I have done so far, I wire brushed, wiped it clean, sprayed a coat of primer, lite sanding, followed with a second coat of primer, and then two coats of color. I plan on spraying a couple coats of clear.

 

[elrey]

You can touch up or repaint painted wheels easily, not so with powdercoated.

 

[dancrim]

Have you checked that these old wheels are true? Most old wheels are far out of spec. and will cause your car to shake. With all of the labor involved and paint, you may be better off getting a new set of 60's when Moss has a sale. I learned that lesson, plus the 60 spokers are stronger.

 

[o1marc]

Not to ruffle any feathers but as a professional custom powder coater I must correct some misinformation here starting with the 1st post:
Magyar: No powder that I work with, other than Red Oxide primer (1 min.@462F)used to prevent outgassing of cast parts, exceeds 400F for more than 10 minutes. This temp will not affect a steel wheel as far as strength or warpage.

Patrick/Nevets: Most of the powders I use are sprayed to a thickness of between 1.5-2.5mil. A standard auto clear coat paint job today is in the 5-6mil range. Clear coat paint alone is in the 1.2+ range not including the E coat, primer, and color coat. Powder is not "considerably thicker".
I do a lot of wheel and just finished a set of '57 Triumph TR3 wheels. Most spoke nipples have a recess before the threads start and if the powder is applied in its correct mil thickness will not seal the connection betweeen the spoke and nipple. While the powder does flow smooth during the cure process it doesnt flow and seal everything as stated above (or below depending on how your post read is set up).
In the pics below you can see that the nipple is not sealed around the rim hole. Hard to tell from these pics but the nipple and spoke are not sealed either so adjusting the spokes should not be an issue. I will say that if done properly I would prefer to have the wheel disassemble and coat each part separately and then reassembled. If coating as an assembly it is wise to have the wheel trued before doing so.
Heat from sand blasting is really only a concern on thin sheet metal such as fenders and such and then only if a non qualified person is doing the blasting. There is almost no heat build at all on a steel wheel and certainly no wheres near what it would take to cause any detrimental issue.
For numbers sake lets say a wheel needs to be a 100 to be in its safe zone. Most wheels are made to exceed this number by probably 25-50% more. When heating aluminum wheels to 500f or more it will weaken the wheel at that temp but when brought back to ambient will usually bring it back to within 2% of its original strength. So your wheel "is" infact weaker but still in its safe zone by 23-48%(Less so with steel than aluminum). When I started coating I heard all the nightmare stories you guys have heard and to protect myself from any liability I did some research and met with metallurgists to get advise form "experts". I have challenged people in that past to show me one documented case of a wheel failure directly attributed to the powder coating process. I am still waiting for someone to show me those results. I did speak to one racing wheeel manufacturer who claimed he had a personally documented wheel failure but it was under the intense stress of track racing., So for the race track I would refrain from coating aluminum wheels. I have raced NASCAR circle track cars for 20 years and have always run powder coated steel wheels with out issue. Many OEM wheels today are coated with powder.
You can see in this pic the with 2 coats of color that the nipple is not seald to the rim. Hard to see that the nipple/spoke connection is also not sealed(looks like the are but trust me they are not) and can still be adjusted if need be. BTW these were coated in a RAL7035 Light Gray that cures at 340F for 10minutes:

 

[Deleted member 8987]

Not considerably thicker? Boy, the street rod guys would like to know that. Seems every time one powder coats a frame, NONE of the bolts will go through the holes again, and they have to grind the coating out of the edges of the hole.

 

[Basil]

Not considerably thicker? Boy, the street rod guys would like to know that. Seems every time one powder coats a frame, NONE of the bolts will go through the holes again, and they have to grind the coating out of the edges of the hole.

I'm no expert but I don't think you're supposed coat the threads - at least they didn't when I had the rear suspension on my E-Type powder coated I had no problems putting my IRS together after powder coating.

 

[Keoke]

I still do not think it will work:
The minuet a spoke wrench hits a nipple it will crack the powder coating. Picking up a rock on a main or back road will cause chipping too. As others have stated damaged powder coat is not repairable in an economic manner. Similarly, assuming this system was the cats meow!!it also would cost an arm and a leg .--Keoke--The--AZ :cowboy:



---This is my story and I am sticking to it.--Keoke-- :laugh:

 

[o1marc]

Your not suppose to coat the bolt holes, any idiot can figure that out. As mentioned earlier about masking threads, we use silicone caps/plugs to keep the threads clean not tape.

 

[o1marc]

Wrong again. If prepped properly powder coating is almost 10Xs more durable than paint from chipping and peeling. A spoke wrench will not chip it off if done correctly. If chipped powder can be touched up just like using touch up paint.

I still do not think it will work:
The minuet a spoke wrench hits a nipple it will crack the powder coating. Picking up a rock on a main or back road will cause chipping too. As others have stated damaged powder coat is not repairable in an economic manner. Similarly, assuming this system was the cats meow!!it also would cost an arm and a leg .--Keoke--The--AZ :cowboy:

 

[Patrick67BJ8]

Not considerably thicker? Boy, the street rod guys would like to know that. Seems every time one powder coats a frame, NONE of the bolts will go through the holes again, and they have to grind the coating out of the edges of the hole.

Ditto! I had to clean-out bolt holes before I could put bolts through the parts in my front suspension. Maybe the coating was thicker than it was supposed to be...I don't know.

 

[Basil]

Not considerably thicker? Boy, the street rod guys would like to know that. Seems every time one powder coats a frame, NONE of the bolts will go through the holes again, and they have to grind the coating out of the edges of the hole.

Ditto! I had to clean-out bolt holes before I could put bolts through the parts in my front suspension. Maybe the coating was thicker than it was supposed to be...I don't know.

You're not supposed to coat holes that other parts go through, nor threaded holes - as stated twice in this thread. The member o1marc said as much (and he does powder coating for a living it seems). I had my Jag rear suspension coated (see pics above) and knew enough to discuss with the place not to coat certain holes that were threaded, or where I knew close-tolorance fittings had to go (like bushing holes). Any competent powder coating shop should know this I'd think.

 

[Keoke]

Originally Posted By: Patrick67BJ8
Originally Posted By: TOC
Not considerably thicker? Boy, the street rod guys would like to know that. Seems every time one powder coats a frame, NONE of the bolts will go through the holes again, and they have to grind the coating out of the edges of the hole.
Ditto! I had to clean-out bolt holes before I could put bolts through the parts in my front suspension. Maybe the coating was thicker than it was supposed to be...I don't know.


You're not supposed to coat holes that other parts go through, nor threaded holes - as stated twice in this thread.

Well yeah that is true, and the better powder coating shops know this and they have a set of plastic bolts they put in all threaded holes to circumvent this problem. Come to think of it the chrome platers do this too---Keoke