re-powder coating?

[stoinkythepig]

I have some big aluminum davits that are powder coated. I want to grind some powder coating off and weld some bullet hinges to them. Is it possible to have them re-powder coated without stripping it all off?

[boosten lebaron]

Maybe but the result will be poor most likely. Unless you have the exact powder used in the first place it will probably look a mess. Its also very hard to powder coat aluminum in the first place so your welding may effect whats currently on there and cause problems down the road.

If you dont care much about it give it a go. If you having a shop do it they will probably insist on stripping the whole thing.

[Tricky Mike]

Another option you might consider... Powder can be stripped. I hear that Benco B17 is the go-to stuff, but have never used it. I did have some success with 5F5, but it seemed to depend on the part I was stripping. Sometimes a total, easy strip and other times it was more like an aid. Same powder (Prismatic) in each case.

I agree that you'll likely struggle unless all of the old powder is removed.

Maybe a local sandblaster could clean them up for cheap?

[MattR302]

I’m just a schmuck with a cheap powder coating gun and a toaster oven in my basement. But in my experience, I have been able to coat over existing power coat and touch up smaller areas. The issue though is the surface finish comes out a little different compared to over bare metal. It’s a little rougher over the existing coat. If you’re having it done professionally though, I’d imagine that they have their own policy about doing this, and probably won’t do it.

In regards to sandblasting to remove power cost, it kinda works, but it’s a slow process. Maybe the glass bead media at my old job wasn’t that abrasive, but I’ve found that using a chemical stripper is much easier.

[Uncle Snake]

I can do a 18 x 8" VW wheel in 25 minutes with 85grit garnet at work. Just don't miss any or it'll outgas and cause bubbles in the new powder. My buddy did these for me with satin over gloss black. Take the time on the prep work if you want good results.

[stoinkythepig]

Thanks for the advice folks. Appreciate it. Might bolt on a set of stainless steel hinges instead.