How long do I need to wait between coats of primer? Like, after I put the self-etching primer, how long do I wait before I apply the urethane primer? And how much of each primer do I need to put on?

Huck. From what I have learned from PPG and Sikkens: shooting the primer, some 10 - 20 minutes flash off time between coats, 3 coats maximum.
PPG curing time "one night, no oven". Sikkens 24 hours. You must sand the cured paint.
When using the same brand you can spray wet on wet (epoxy on self-etching) within 2 hours without sanding. Hope this helps.
Rob

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www.si.hhs.nl/~rob (http://www.si.hhs.nl/~rob)

This is all depending on the temp and the solvents and the primer being used. Not the brands but the technology.

If you are using low VOC like 2.1 those times may need to be stretched out. If you are in a very cold temp or have too slow reducer, this may also stretch out the time between coats.



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