Oil based painting... 3 days, not dry

bnddbl07 · July 5, 2023, 4:53pm

Hey all. Came across something that I’ve never experienced before. I have a feeling that “humidity / wait longer” is the answer… but I’ll ask anyway…

I have PLA printed castle that I’ve base coated with “2x rust oleum spray paint”. I’ve never realised that it was oil based (I stray, I put it away…no need for clean up…). I love how it covers so well. For this project I wanted some more texture and such to the finish, so bought some Art oil paints from Michaels, as I read/ knew that I shouldn’t be putting acrylics over oil for long term quality.

So. Saturday I put the base coat on out in my garage. Sunday mid day I the next coat using the Oil paints via sponge. Monday morning, the paint is still wet. Ok, It has been warm/ humid in the garage, (which normally isn’t a problem for Acrylic), so I bring the castle inside. It’s now Tuesday afternoon… STILL WET. What the heck man… ? I’ve had a fan on it for the last day as well.

I don’t think a heat gun/ floor heater will do anything better as that will be similar to the garage (way less humid though).

thoughts? thanks!

Matthew · July 5, 2023, 7:03pm

Hey there,

I have used oil paints for many years now on canvas, generally I will check on the paints in around 2-3 days and see if they are dried up, but depending on the brand and color and how much paint was used it can take upwards of around a week. Oil paints usually take a long time to dry because oil dries a lot slower than water does. Personally I wouldn’t use a heat gun, could cause problems with the paint. Unfortunately your answer will just be to give it more time.

Thanks,
Matthew

bnddbl07 · July 5, 2023, 7:06pm

Well… that’s not good! Deadlines! The I Like to Make Stuff- Patreon Maker Camp is coming up for this!

Great to know though,. thank you very much for the reply.

Washing it off couuuullldd be a solution but my gawd that would be messy. :S

Matthew · July 5, 2023, 7:27pm

Hey that’s pretty cool! Good on you for getting that opportunity! Technically yes you could wash off the old paint, but that would be awful, how long until the camp comes up for this? Theoretically you could use a heat gun to speed up the process but you would have to stand there forever. If you have a space heater or something like that you could use that, not that I necessarily recommend it, but in a pinch it will work for sure. You would want something to keep it spinning, if you have something from a paint booth that would be great, if not I believe they are pretty cheap to grab from hardware stores.

Another thing that you could try that is to leave it outside and let it bake in the sun. This could help speed up the drying process as well. I will definitely recommend not going straight to the max temperature on the heater though, if you put it too high you can crack the paint. Put your hand about where the model will be, it should feel warm but you should be able to keep your hand in front of it for a little while without getting burned, this will help to reduce/eliminate any cracks or imperfections formed by a quicker drying time.

Hopefully this helps, I wish you the best of luck!
Matthew

bnddbl07 · July 5, 2023, 7:32pm

Thanks! I roll out July 28th. So not Immediately. But the colour didn’t turn out right, so There will be more layers… so I need the time.

I wasn’t sure if outside was a good option or not, so thank you I can definitely do that. My front porch is covered, so it will get a heat without the bake.

Matthew · July 5, 2023, 7:33pm

Great!

Keep me posted on how it goes! I got my fingers crossed for you

Matthew

bnddbl07 · July 5, 2023, 8:07pm

Thank you sir!

bnddbl07 · July 10, 2023, 12:47pm

Progress! but a learning experience.

Outside drying worked. took a day and half though.
Some of this time was outside, not under cover… The paint is fine, but the PLA, clearly didn’t like the heat it as the started to warp. (not surprising as I knew this about PLA and heat, but I had never experienced it.). The castle is in 4 pieces (solid corners, joining on the 4 side mid points), so the warping happened at the joints. But I can work with that, Wasn’t horrible, and I can add some “battle damage” or something.

So there ya go. Dried eventually, but with added… features… (and learning experiences)

I’ve not added a few more coats of spray paint to bring it the colours I was going for. (the part of the story I didn’t mention before was that oil paints I used was a “Van Dyke Brown” and VDB lighten with White. Apparently Van Dyke Brown has some red in it, because the Lighten colour… turned out Pink… I wasn’t going for Barbie’s Dream Castle… so that had to change.

Thank you very much again for your help.

Make Well!