Curing painted enclosure in a toaster oven for first time. Any tips for a noob?

[Bandwagonesque]

hi folks. I went and picked up a kitchensmith toaster oven from target last night to try curing enclosures for the first time. Was the only one I could easily find with a sub 200 degree range. My last build, I had sprayed the enclosure and left it to dry for a week and was still stunned that the finish was soft enough to take up my fingerprints and ruin the finish a bit. This time I would like to bake the enclosure to cure it after the initial primer and color coat, just before I stick any decals or graphics on and then clear coating and curing again before calling it good. From my research, i'm assuming I should go no higher than 200 degree's but can anyone with any experience tell me how long I should cure for or can anyone offer any tips or tricks that may help me avoid any accidents this first time around? Is it ok to cure after the decal and clear coat have been applied or will I run into cracking or yellowing? how long should I wait to cure between coats of paint or clear coat applications?

[vigilante397]

I see lots of different numbers on here, including a lot of long times at low temperatures. I got good results with 10-15 minutes at 300 degrees, that worked fine for me.

[GGBB]

More than one way to do it as Nathan said. If you are going to bake after decal and clear coat - you probably want to avoid high temps - I've heard that decals can brown if baked too high. It's been a while since I bothered finishing an enclosure, but I think I used to do 30 minutes at 200 - seemed to work well. Check your paint cans for max temps - not sure if they list them or not. There's bound to be differences between paints that might merit temperature or time adjustments of you are looking to push the extremes. The safe route is lower temperatures for longer times.

[rutabaga bob]

What paint are you using?  I ask because I used to use Rustoleum, which never really hardens.  Did the 'wait a week to clearcoat', and the oven bake as well.  Nope.

[vigilante397]

What paint are you using?  I ask because I used to use Rustoleum, which never really hardens.  Did the 'wait a week to clearcoat', and the oven bake as well.  Nope.

I used Rustoleum exclusively when I did rattle can painting and never had an issue with oven baking. I originally did primer -> bake -> primer -> bake -> sand -> paint -> bake -> paint -> bake.

From that point you can either leave as-is or throw on a waterslide and clearcoat -> bake -> clearcoat -> bake, then done. It was excessive and I eventually went to zero primer, one coat of paint, one coat of clear.

[rutabaga bob]

Nathan, I'm glad you could get it to work - I never could, no matter what.  The paint would be soft even months later.  Don't do much finishing any more...DupliColor primer, then maybe some acrylic pour/swirl stuff.  Topped with acrylic clear.

[vigilante397]

Nathan, I'm glad you could get it to work - I never could, no matter what.  The paint would be soft even months later.  Don't do much finishing any more...DupliColor primer, then maybe some acrylic pour/swirl stuff.  Topped with acrylic clear.

It's probably also worth mentioning that my prime Rustoleum years were while I was living in the Mojave desert, hot and dry 300+ days of the year makes excellent painting conditions. I switched over to powdercoating before moving to the midwest, so the temperature and humidity of the air doesn't matter much.

[Mark Hammer]

Two words.  Thin coats.  I repeat - THIN coats.

[bluebunny]

Two words.  Thin coats.  I repeat - THIN coats.

^^ This nugget of wisdom needs a sticky thread of its own. 

I have a few examples from years back when I was learning my craft (the hard way, of course): still soft paint...   

[Shoeman]

Mark's advice is excellent.  As far as baking goes, we're all just guessing and you'll have to use trial and error and cross your fingers.  I work in a big collision repair shop and while I'm not a painter, I have gone over the flash/cure specs with those guys when we have to use a new or different paint product.  Very specific info is given for each step.
"It is impossible to identify a single recommended temperature setting. Your best bet is to check with your paint manufacturer, as they can tell you exactly what temperature your paint booth should be set at to properly dry and cure your coating."
That's a quote from GFS, our paint booth manufacturer and it pretty much sums it up.  I've switched to using my old airbrush and Testors model paints with good results.  There is even water-borne model paint out there now, but I have had one very slow to harden experience with that sadly.   

[Mark Hammer]

Thanks for the vote of confidence.  The advice to apply and bake thin coats also applies to any clear-coat one applies over graphics on a painted box.  "Chemical clashes" between some paints and clearcoats can result in unpleasant wrinkling of the surface.  I've had to completely strip more enclosures than I like to think about, simply because I was impatient and sprayed a single thicker clear coat over what was also too thick a coat of paint.  Baking can cure the entire coat, if its thin enough, OR it can provide an unwanted "protective" layer on the surface of too thick a coat.

FWIW, my own graphics consist of simple legending, using black, white, or occasionally yellow rub-on lettering from my stash.  Most sheets of rub-on lettering come with a very limited supply of the letters I need most often.  I hate finding out that the last two 'Zs' I had in that font have wrinkled because I didn't spray thin enough.

[davent]

Mark's advice is excellent.  ...
... I've switched to using my old airbrush and Testors model paints with good results.  There is even water-borne model paint out there now, but I have had one very slow to harden experience with that sadly.

I was always really pleased with Golden brand, artist's acrylics and airbrushes or any other object to move the paint onto and around the painted surfaces. Endless colours and an on line tool that you you the formulas for mixing custom colours from their paints.

No oven needed for the paint but you can speed up drying with a hot air gun if you want.

Clear waterborne lacquers for instrument finishing worked great overtop the acrylics and no nasty fumes from rattle cans to deal with, fast drying and any type of sheen you desire.