Discussion
Past couple of times I've painted (interior) heavy plastic trim pieces I've oven baked them to "harden" the paint.
Basically paint, leave to dry for several hours then into the oven at about 80C for an hour.
Seems to have worked quite well.
I now have a couple of door handle covers which are very thin plastic. No issues painting but I expect they will deform at anything beyond 40-50C.
Is it work baking them once painted at such a low temp?
Basically paint, leave to dry for several hours then into the oven at about 80C for an hour.
Seems to have worked quite well.
I now have a couple of door handle covers which are very thin plastic. No issues painting but I expect they will deform at anything beyond 40-50C.
Is it work baking them once painted at such a low temp?
Why do you want to bake them? The only advantage to baking at a bodyshop is production speed, meaning you can get a car out and another one in? It doesn't do anything to help the paint otherwise?
Modern lacquers that are baked are done in the booth at 60c for about 40 mins or whatever the TDS states, I wouldn't go up to 80.
1k paint just air dries as the solvent evaporates and 2k paint is a chemical reaction between the paint and hardener. None of that requires excessive heat, the paint atomises and lays down nicer at about 20c for spraying but otherwise I wouldn't worry about heat?
Modern lacquers that are baked are done in the booth at 60c for about 40 mins or whatever the TDS states, I wouldn't go up to 80.
1k paint just air dries as the solvent evaporates and 2k paint is a chemical reaction between the paint and hardener. None of that requires excessive heat, the paint atomises and lays down nicer at about 20c for spraying but otherwise I wouldn't worry about heat?
21TonyK said:
DaveF-SkinnysAutos said:
Why do you want to bake them?
Sounds like I've been incorrectly assuming baking helps harden the paint further than air drying.Oh well, question answered and problem solved.
Thanks
E-bmw said:
I have used a hair drier to help/quicken etc before now just to warm through and aid hardening.
Yes, a hairdryer/hot air gun will help, but there are a couple of factors at play and there isn’t a clear answer for every occasion.There are a couple of elements, lets assume you are using base paint which is 1k paint, its usually mixed 1:1 with thinners or its ready mixed in a rattle can. The first element is flash off time, thats the time you need to allow between coats to stop it running, thats usually just a couple of minutes at around 20c. The second element then is the actual drying. The TDS sheet will give details for the specific product but base only needs about 20 mins before you can top coat with clear. But clear itself can vary between half an hour for a smart repair lacquer with a fast hardener to 24hrs to touch dry for several coats of UHS lacquer. Then it can take several weeks for it to fully harden, and shrink back and fully gas out.
You can use heat to speed up that process, but you need to be careful that you allow the solvent to escape, so too much heat will skin it over trapping the solvent beneath leading to blistering further down the road, it could also cause it to shrink back. Likewise, in the depths of winter without some heat it’s going to take forever to dry. Do you need to put it back on the car quickly, is it going to pick up dust nibs in the drying environment, etc.
In short, no harm in using heat, but if its warm and its not a rush job it’s probably not needed. Read the TDS and then apply common sense depending on the circumstances.
DaveF-SkinnysAutos said:
In short, no harm in using heat, but if its warm and its not a rush job it s probably not needed. Read the TDS and then apply common sense depending on the circumstances.
TBH, I only just warm it a bit, or as you say, if it is sunny, just park in the sun instead.Forums | Bodywork & Detailing | Top of Page | What's New | My Stuff