2nd coat problems

[Austin_Dan]

I am new to powder coating and I am having trouble on 2nd coats on aluminum parts...

more specifically I am trying to do a valve cover.. I tried to do a metalic silver first, then the lolipop blue 2nd.. the first coat always looks good, but the second coat looks terrible...

I tried over super chrome as well, and I tried with steel pipe...

the second coat looks all washed out, like it wouldnt stick in some places, or like it just ran off?

I did part of a mandrel bent ss pipe for practice and on the inside of the bend it looked pretty good, but on the out side the blue is terrible... it didnt cover at all.. at the same time (cured at the same time and everything) I did a similar pipe with no base, just the blue on top of the steel, and that looked great...


what is the problem with two coats?

TIA

[jtagger19]

apply the second coat at 150-160 deg of temperature
and make sure you have a good ground .
you won't have any problems.

[filburn]

Im a little confused

what I am hearing is you already applied the first coat and cured it and let it cool down to room temperiture. What your suggesting is to re-heat the part to 150 degrees, spray it with the second coat, pop it back in the oven to cure it a second time?

[bzer1]

I believe what he means is cure or partially cure the first coat. While that is curing do your color change. When the part is where you want it for the second coat, take it out of the oven and keep checking the temp till it gets down to around 150f and shoot your second coat. Now you fully cure the part. Keeping the part at an elevated temp helps the powder to stick and stay in place. To repeat an important point...Always make sure you have a good ground.

[DALE]

This topic has been beat to death in the old posts. Go through the archive and you will finds tons of advice directly related to your problem.