Silver Problem

[Guest]

hey guys another prblem for use to solve lol i was doing a wheel today based it up bright silver cured it laquerd it put it in the oven and it dulled the silver down and turned grey i thought it was because the wheel was still a tad to warm so based it silver again waited til it was cold coated it with laquer baked it again and same happened ive tried this4 times now and still happenin any ideas ?

[wiseguyz]

Re: Silver Problem

I assume you're using a bright silver powder as a base. Why are you using laquer as a topcoat instead of clear powder and then baking it? Not sure laquer is designed to be baked in the first place.

[Guest]

Re: Silver Problem

Alll basecoat metallic's should be fully cured before applying the topcoat then allow to cool. You must use a very clear and smooth topcoat and do not exceed 2 mil's...

[adiemwell]

Re: Silver Problem

yes it is clear powder iam using ive tried to coat the wheel when its cold then bake it off and its just changin colour to grey also when i spray cold i sumtimes get small cicles like the elctrostatic charge is stoping the powder from flowing onto the wheel ect ?

[wiseguyz]

Re: Silver Problem

That is helpful info. Like KING said, be sure your basecoat is fully cured before applying the clear or it may discolor more than it should. The spots you're experiencing are called "starbursts" which is back-ionization that is doing exactly what you say....repelling the powder and causing it not to stick. The solution to that problem is preheating the part to about 180 f, then decreasing your air pressure, increasing your powder flow (if your gun will let you adjust that), and increasing your distance to the part to minimize the back-ionization effect. Also, make sure you have a good clean spot for your ground path to help minimize the static buildup. Try to make slow even passes so you can get good coverage without going back over the same area. Multiple passes will magnify the problem.

Best of luck.