Still slowly working on this project, jumping around from issue to issue. I have a front drum wheel that's missing the brake plate, so I bought the above plate from one of the big eBay bike parter-outers. Seller is in Canada, price was good but shipping was pretty high, it was a whole wheel, I messaged and said I'd pay the full price for just the plate if the shipping was cheap enough. So, I end up paying $133 USD total to my door for just the above brake plate, as shown.
That's an extremely good deal, BUT...
The black spray paint comes right off, even with modern useless paint stripper. BUT...
This hub has been CHROMED. But, that's not all. The chrome is a mess. It is completely covered with big and small pits. And, it is ROUGH. It looks like it was hit by a sand blaster, but I know it wasn't. Or, it looks like it was covered with another plating, like nickel or something, but I'm pretty sure that's not right either.
Whatever was done to it, it was done with the plate fully assembled. If you look at the full size image above, you can see that the vent cover was in place when whatever was done happened, and the cover protected the chrome under it, which is gorgeous.
Here's what I'm talking about. The chrome under the cover looks great. Everywhere else is rough and has big and small pits.
So, I want to get rid of the chrome. I Google it. Acid is popular, but the plate is a combo of mostly aluminum with some cast-in steel parts, there's no way to control what's going to dissolve.
The other popular method is sand blasting. I try it. NOTHING. I guess my blasting media isn't hard and sharp enough.
So, last resort, I go to a black emery buff compound on a sisal wheel. Results shown above, where I hit a corner right next to the vents. Deffinite improvement, but the emery is not nearly aggressive enough. It will never get the big pits out, and it will take forever to get all of the tiny pits out.
All I want is to remove the chrome, so I can get to the easily polished aluminum.
Some more images of test areas with the emery buff compound to give an idea what I'm dealing with. In the last pic, I was able to really bear down on the edge of the plate with the sisal wheel, and I got all the pits out, but the edge has started to round.
I'm open to suggestions. What's really needed, in my opinion, is a silicon carbide buffing compound, but they don't really make exactly what I want. SiC valve lapping compounds are generally too fine for bulk chrome removal and are a bit expensive. I've been looking at coarse SiC 60/90 grit, which isn't too expensive, mix it with axle grease, and use it on a brand-new, dedicated sisal wheel.
I did a test using a medium grit SiC sanding belt on an inconspicuous place on the plate, and it it ate through the chrome like butter. So, SiC will work, I just need it in a form that I can get into the nooks and crannys.
I'll wait for suggestions and comments, and then I'm buying SiC powder.