Triumphrat

grayghost · 10-10-2007, 10:39 AM

Hi Everyone,

I would like to pose this question to those of you that have experience with powder coating. I have a 1992 BMW R100GSPD Paris Dakar and the rear rack has the factory black powder coat that has faded to a dull black.

I want to renew the bike to pristine condition and my question is that if I remove the rack and take it to a powder coater, can they apply black powder coat over top of the old black powder coat OR do I need to have the rack sand blaster first down to raw metal?

The second question is that there are threaded holes in the rack, is it better to have the rack powder coated with bolts in the rack (thereby protecting the internal threads) or to tap the holes afterwards to restore the threads?

Any help is most appreciated.

BadMouth · 10-10-2007, 11:19 AM

LOL, I just came back from the powder coater's a half hour ago.

In the case of the one I'm using, they bake off paint and impurities and finish it off with sandblasting as part of the powdercoating process (i.e. included in the price). Some also use acid dips. I'd let them handle it.

As for being able to powder coat over powder coat, yes they can, but they'll probably strip the part down as their usual way of doing things.

On the threads, they told me that they've had customers who severely underestimated the hardness of the powder coat and told them just to spray the part and they'd tap all the threads when they got the part back. They said people usually end up breaking several taps trying to clear the threads. They're going to plug my threads. If you're not sure about your powder coater, I'd put some bolts in there before dropping it off.

The one I'm using charges a $35 setup fee plus around $20-40 for each part.
They use black so often that they usually waive the setup fee for it.

grayghost · 10-10-2007, 02:46 PM

Thanks Badmouth for the info. Much appreciated.