I'm prepping a set of brake calipers to be powdercoated. When finished, I want them to be baby's butt smooth, not grainy/bumpy like the stock calipers. How much work do I need to do before coating them to get that kind of a finish? Will the powder act like a typical wallpaint and slightly smooth out the rough/low spots?

I picked up a Ryobi 5" random orbit sander last night ($50, not too bad) and started working on one of the fronts, 60 grit. There is still a bit of pitting, I'm just curious if I need to really spend much more time on it, or eventully go up to a finer grit, or if it's ok to leave it as is and let the powder to the rest of the work...

 

work on the casting seams the most and hit the rest of the surfaces with what you have. If you want the smooth look then getting the seams worked out is the most important. The powder will fill quite a bit but the more smooth you make it the more smooth it will be after the process.

Most preople try to get rid of the seams when/if they take the time to powder coat the calipers so that is my strongest advice.

 

Primo is right. The powder is thick enough that as long as the person doing it uses enough coats and lays them on well enough, it will smooth out minor pitting.

But if you want SMOOTH, make sure you grind out those seams, as well as any deep marks on the calipers.

 

Thanks guys, I'll probably do a bit more touch-up work on the caliper I'm currently working on, then leave it alone and move on to the next. At this rate, each caliper should take me about an hour to do, 30 minutes per piece. The sander doesn't get in the odd shaped crevices, so I'll pull out the Dremel for that.

 

Oh yeah, make sure you clean the calipers REALLY well before giving them to the powdercoater.

If you don't mind me asking, where are you taking it to be coated?

 

I thought the coaters typically did a complete washdown with heavy chemicals before coating? I intended to give them a good washing with soap/water, then give them a light coat of WD-40 to prevent rust and stick them in a Ziploc bag. Is heavy cleaning not a typical step? I'm not asking them to strip paint or anything, just remove whatever surface oils they may find on there (such as my WD-40).

Todd is having his guy take care of them... custom color, 4 calipers, one valve cover, less trouble for me.

 

Cleaning is a typical step, but I like to clean everything I send out myself just to be certain.

 

they will definately acid wash them and most likely give them a quick shot with a fine sand blaster as well before that