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DocHarley
01-12-2016, 04:22 PM
I know epoxy, 2k primer and filler shrink, how long does it take to stop shrinking? In other words, how long should I wait after body work before applying paint?

Here a pic of some SPI epoxy left in the mixing can for about one month. Lots of shrinkage.

Rick_L
01-12-2016, 05:30 PM
The rate of shrinkage will vary with temperature and humidity. Heat and dry will help. Roll that body out in the sun when you can.

The best way to avoid problems is to avoid buildup. If you only have a little bit of stuff, it can't shrink much - because shrinkage is a percentage thing. A percentage of almost nothing is very small.

DocHarley
01-14-2016, 05:34 AM
Does it stop shrinking after so much time and if so do you know how long before it stops.

Rick_L
01-14-2016, 05:43 PM
Doc it is very hard to say what that time frame is.

If you use quality materials, apply them per the p-sheets or instructions, especially with regard to build thickness - then shrinkage should be minimal.

Barrier type sealing coats such as epoxy primer also keep topcoats from damaging what's underneath.

It's nowhere near the old days of lacquer primer and lacquer type one part glazing putty.

Maybe I should turn this deal around. Are you having a problem with a specific material?
,

DocHarley
01-20-2016, 03:39 PM
No problem. On my quarters, I had to pretty much reshape them because Golden Star sucks, (can I say sucks? lol) I did a skim coat of filler so I'm sure there's a few areas where the filler might be 1/6-1/8 or more thick so I wanted to make sure shrinkage was not going to be a problem. Once the body work is done, I will wait at least a month to paint and also let the coatings cure in the sun for a few days like you recommended then re-check the panels again using guide coat. FYI, I'm using SPI epoxy and primer and Evercoat Extreme filler which the internet people say are all top of the line products.

Thanks for all your professional help! It's greatly appreciated!!!!