Can I mix types of powder?

[Hemi-T Amateur Metal Finisher Find all posts View Profile Close Hemi-T]

I have a project where I'm trying to match an existing color. It's somewhere in between your "pale yellow" and "bright yellow". I figured I would try mixing bright yellow with gloss white to get a match. My question is: since bright yellow is a TGIC powder and gloss white is a hybrid epoxy powder, can I mix these without causing problems? Any special tips, procedures, or potential problems? Thanks in advance!

Hemi-T

[DALE Experienced Metal Finisher Find all posts View Profile Close DALE]

mixing powder

You need to remember this is not paint! Powder does not mix like you think, it will have yellow and white spots but not a mix. You can change the shade some by adjusting cure temp and time but not much. Or you can change shade a bit by using different base coats under the color you want, darker colors make the yellow a bit darker,chrome makes it a bit lighter. Powder types can be layed over top of each other with out problems. they don't mix.

[Hemi-T Amateur Metal Finisher Find all posts View Profile Close Hemi-T]

Thanks for your reply Dale. As my one star rating implies, I am indeed new to powder coating. I've collected all the necessary equipment, but have yet to actually coat anything. Right now I'm cleaning up an old electric oven to use for curing. For the most part, I'll be powder coating car parts. I got my powder coating kit last week, and a sand blaster yesterday. Once I get the oven working, I'll coat a few pieces of scrap metal for practice.

Thanks again,

Hemi-T

[Hemi-T Amateur Metal Finisher Find all posts View Profile Close Hemi-T]

I got everything set up tonight, and powder coated a couple of pieces of scrap metal. They turned out great, and with a little more practice, I'll be a powder coating madman

Hemi-T

[DALE Experienced Metal Finisher Find all posts View Profile Close DALE]

enjoy

Glad I could help. I suspect your garage will soon have colored pieces hanging all over the place. The more you mess around with it the more interesting it becomes. Welcome to powder coating.

[Hemi-T Amateur Metal Finisher Find all posts View Profile Close Hemi-T]

Hey Dale, I coated a couple of other parts tonight, and watched carefully as it cured in the oven. I put an oven thermometer in with the parts so I could more accurately monitor the temp. The powder looks like it starts to melt at about 250 degrees. One piece got a little too hot at 400-425, and it looked a little over cured, and even started to smoke a little. The finish was not as smooth or glossy. It looked like 350 was the best temp. Also, how long should it cure? As soon as the parts got up to 350, the powder was completely melted, and had a nice glossy finish. Should I leave it at that temp for a period of time, or start to cool as soon as the powder is fully melted?. I read that cooling slowly will help reduce orange peel and keep a glossy finish.

Sorry about so many questions. This is gonna be real cool when I get the details worked out and get a few more practice parts done. I really appreciate your help

Hemi-T

[DALE Experienced Metal Finisher Find all posts View Profile Close DALE]

temp

350F works well for most things, 20 to 30 min should work well for your set-up. Use 20 min for thin aluminum parts and 30 for heavier stuff. These times are with oven preheated. stay under 400F the closer you run to 400 shorten the time 10 to 20 min but lighter colors will darken easily. Orange peel happens for several reasons 1 not a good enough surface cleaning but this also usually causes cratering 2 coarsely ground powder but you don't have the equipment to measure this 3 to fast of a cure which doesn't allow the powder to flow long enough to get smooth 4 film thickness too thin or thick. Akzo is at interpon.com. Also yes it helps finish to turn off oven and open door about an inch and let cool slowly but this doesn't really do much for orange peel but when pulled right out of oven color may get a milky-hazy look to it. If this happens most of the time you can lightly rub the part with a paper towel or clean rag to get rid of it but not always.