Hi all,

I just got parts back from the powdercoaters and they've coated the braking surface of the brake drums. Is that going to cause a problem? I feel like it will.

Thoughts?

Send your brake drum, brake plate and shoes to a brake specialist.
They will fit oversize linings to your shoes, skim the drum and machine the linings to suit. Result = a better brake

Sounds good but I don't have the coin for that. The powdercoaters can blast the powdercoat off.

One more reason NOT to "powdercoat." The ENTIRE drum evidently got coated, inside as well as out.

Also, a reason not to hand off a job to someone who doesn't know what they're doing.

Reminds me of the guy who smeared grease inside the brake drums so the brakes wouldn't wear out as fast!

The thickness won't be uniform so you will have a egged shaped surface. Find a auto machine job that turns drums and have them skin the powder coat off

I was able to remove some unwanted powder coating using an angle grinder with a paint stripping disk, be careful ! I have stopped powder coating my frames due to a lot of issues. Mainly the engine and transmission mounting plates have a really thick coating causing reduced area in the engine and transmission area. When I was assembling the last bike with powder coating I removed as much as I could from the frame lugs and mounting plates.Another issue you may face is when the brake hubs are coated each spoke hole will have a heavy coating. When you spoke and true the wheel this coating may break off due the the spoke tension. If it doesn't break then, be sure to check it occasionally after you ride it. Alternatively you might find a way to remove it from each spoke hole prior to assembly.

It will absolutely cause a problem - besides creating an uneven radius, it will melt onto/into your brake linings. We see this problem at work with the wheels we get for our electric mobility scooters. They come from China so there's no sending them back, we just have to get the powder coating out of there however we can. If it's thin it can be sanded out, but if it's thick sometimes we have to resort to a hammer and chisel. BTW, for sanding, one of those "sanding screens" seems to work best.

FWIW, I had the same issues a decade ago. I just sanded the powdercoat out of the drum and never had any issues.

The powdercoaters can blast it back out. I was going to sand it lightly after that.

Have a look at the blasted surface first, if its not really rough then it will help not hinder braking and also bed new shoes in.

I use paint stripper- the type that's labeled "aircraft quality".applied with an acid brush. It takes several applications because I use a thin coat to avoid slopping it around. It continues to cure for several days, so the sooner the better. Once softened all the way through it can be sanded easily to finish up. You just have to be careful to avoid getting it on surrounding areas, but if you do, it works slow enough to wipe off before damage is done. I had a Triumph rear hub done once, and had to clear the spoke holes with a drill bit. I now paint the hubs, along with the oil tank. It's expensive to have the front done in silver-gray, So I paint that as well. I sand some off (but not all) on bolted together flanges, and clear some holes with drill bit or tap as needed.Where they mask the top threads on the sliders sometimes a little bare metal doesn't cover up when assembled- I touch that up with several coats of a black permanent marker so it doesn't rust. Works well. Electrical grounding points need cleaned as well. I also take pictures of parts that show areas to be masked, and a pic of all small parts laid out- this helps prevent missing parts. At first I had them use the most glossy black ( they call it "wet-black"), but now I have them tone down the gloss a little, and it comes out much nicer. The biggest problem is orange peel- mostly side covers and headlight ears. I inspect when I pick it up and have them re-do anything I don't like. They use stripper when respraying, that's where I learned about it.

Gents … You didn't ask, but I'll share this with you. Some years ago when I was restoring a Goldie, I had spray painted a 190mm rake drum with the correct(?) silver automotive paint. After a few years of umm spirted riding, the drum became, ugly rusting down in the fins and the paint beginning to curl up.
So for the last 190 brake I built up I sourced silver high temp 'caliper' paint from Eastwood and brushed it on paying attention to paint it down into the fins. To 'properly' build up this brake I also had the drum skimmed and the shoes of the Phil Pearson TLS backing plate turned to fit. Works nicely for a good 'whoa up' from speed. This paint flowed nicely and works great. It worked so well I unspoked the earlier brake, stripped it and repainted it too. On n on we go, sheeze.

I've also used the locally available black caliper paint to brush on rear brake drums.

where do you find these powdercoaters?

the two shops I've used mask off ALL areas that should not be coated. Brakes, bearing recesses, etc.

Yes, concur with Richrd. The powder coater use, knows what their doing. They mask off all of the proper areas on frames and cycle parts. Once in a while I point out an area I want masked off.