Powder Coated Wheel Lug Seats

[schwarz633]

I just had the wheels on my FX35 powder coated and it appears that nothing was masked off. I asked him about the lug nuts seats and he said it wouldn't be a problem, just to check the torque periodically. Not exactly a confidence builder. Some further research reveals there are an equal number of people with opposing opinions on this.

After some hand sanding on the inner bore I went ahead and installed them for now. I'm wondering if I should revisit this and remove the coating on the tapered lug nut seats and possibly go over the flat surface on the back that rests against the rotor hub. I figure I can use sandpaper and a flat plate of some sort to flatten the back. Does anyone known of a tool that I can use on the lug nut seats? I need to physically confirm this, but they are probably 60° angle.

Possibly this:

https://www.amazon.com/gp/product/B07G1652GN/ref=ox_sc_act_title_1?smid=A2JCJW8DIP4OKB&psc=1

[Superman]

You are right to be asking these questions. I won't insult Neanderthals by comparing them to your powder coater. I wonder if there is a way to dissolve the coating and thereby avoid physically resurfacing/modifying the lug business surface. Perhaps not, since I think powder coating is a plastic coating. Polyester?

[Superman]

It looks like powder coat can be removed using a chemical stripper.

[Scott Douglas]

I always judge the Fuchs wheels on BaT that have been 'redone' by whether or not the lug nut surfaces have been coated. It's a good indicator of how well the job is done and how knowledgeable the restorer really is too.

[Shaun @ Tru6]

Even with Cerakote going on with micro thickness, seats are always protected. Not really hard to do with an old set of lug nuts. The fact is most people aren't qualified to do what they do.

[look 171]

I understand that a machined mating surface is important but if the mating surface of the lug nut is chrome, that also makes it inconsistent? Makes no difference?

[Dantilla]

A guy at a race shop told me that with freshly painted or powder coated wheels, they torque the lugs to spec, loosen them again, on and off about five times.
After that, torque a final time to spec, and they've never had an issue.

[Jeff Hail]

Too many times I have seen the backside mating surface coated as well as the lug seats. I have even seen two sets of factory Porsche Centerlocks with an after sale powder coating applied on every surface possible. We determined the uneven film thickness applied caused a run out based vibration. Expensive day for the coater but he stepped up and bought the owner a new set of wheels.

Powder coating seats and mating surfaces are a big fail in my opinion.

[911pcars]

I would use an abrasive material somewhere between a metal cutting tool and polishing compound, both of which are either ineffective or overkill.

Try to remove the coating gradually. Powder can be sanded off gradually, so I would suggest an abrasive material shaped like the lug nut seat to do that.

[Racerbvd]

Originally Posted by Jeff Hail

Too many times I have seen the backside mating surface coated as well as the lug seats. I have even seen two sets of factory Porsche Centerlocks with an after sale powder coating applied on every surface possible. We determined the uneven film thickness applied caused a run out based vibration. Expensive day for the coater but he stepped up and bought the owner a new set of wheels.

Powder coating seats and mating surfaces are a big fail in my opinion.

Not only that, buy the heat can literally melt the powder, when it is on the back surface and basically welds the rim to the hub. I have seen it happen.

[rfuerst911sc]

Would a small drill operated wire wheel remove the powdercoating in the lug holes ? I have one that is small in diameter and has a round face that I occasionally use to remove built up crud . Fits in the lug holes perfectly and doesn't touch the face of the wheels . Obviously it is better if the lug recess is not painted .

[LEAKYSEALS951]

I have no idea what I'm talking about- having never done this, but, would it not make sense to put (something like) a light layer of valve lapping compound into the area, and spin a spare lug nut against it to remove the unwanted layer?

There would be various ways to spin the lug nut depending on the speed needed and what you have laying around.

edit- wouldn't address the backside though.

[Shaun @ Tru6]

I would take them back to the shop that coated them and have them deal with it. If they won't, ask them for a small jar of this:

Super Speed Industrial Paste Stripper

I would cover the wheels with tape, line the holes with PVC and plug the holes and using a syringe, put about 2cc's of stripper in each. Let it sit for 30+ minutes, pull out the plugs and carefully scrub with some kind of round head brush. Carefully rinse with water.

If you go this route, don't get the stripper on your skin for longer than 30 seconds, it kills skin and the underlying new layer is very tender for a few days. Get proper gloves or triple 6+mil nitrile for a small job is safe.

[Chocaholic]

Doesn’t seem like such a big deal. Score the contact surfaces with some fine Emory cloth and install wheels. Check torque a few days later and you’re done.

[Arizona_928]

Originally Posted by Racerbvd

Not only that, buy the heat can literally melt the powder, when it is on the back surface and basically welds the rim to the hub. I have seen it happen.

I've had a new set do that.....

[304065]

Shaun you may want to turn on the heater in the paint booth. . . it's snowing.

[smadsen]

There is a small tool that cuts those mating surfaces. It's important the surface matches the lug nuts closely. The lapping compound and a sacrificial steel lug nut on a speed wrench sounds the cheapest gambit. Back & forth motion, like lapping a valve.

[bleucamaro]

Mask with a flash breaker tape (platers tape) and apply straight MEK That will soften the powdercoat enough to remove. Jasco may also work.

removing it with abrasive will just clog the abrasive and be annoying.

Alternately, don't remove it. If it's well applied and even, why do you need it removed?

[cstreit]

I’m not sure this is a process that relies on friction. Any engineers want to weigh in?

[1990C4S]

If the friction on the head were immaterial then a lock washer wouldn't work.

I believe that technically the threads under tension alone should keep a bolt tight. Obviously both are factors, loctite locks a thread in place while lock washers create friction on the mating surface.

Personally I would be more concerned about anti-seize on a stud than powder-coat, yet anti-seize does not appear to make studs come loose. The one caveat might be thickness, an uneven mating face would not be good.