I have tried to coat a billet aluminum head for a jetski about 6 times now, trying everything i can think of to prevent it from outgassing. Tried preheating at 450 for an hour…no go. Bumped up to about 500 for 2 hours…. still no go. Tried shooting at 200F and even about , everything still causes outgassing bubbles. Today I tried twice to sand the bubbles down on the base coat, only to have others pop up in new places while second coat is curing. Any suggestions/advice guys? 🙁
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