Which clear coat is better for fiberglas door?
I "painted" my f/g Thermatru door with Zar oilbased stain. I want to clear coat it on Sunday (next day the sun is out). I have either Thermatru water-based poly that is supposed to last for 5 yrs, but my can expired "21 20.09", or new can of Sikkens Cetol Door and Window Clear Satin.
Thermatru can be recoated in a matter of hours, no sanding between coats. Recoat as necessary to maintain gloss (satin), just wipe door down with mineral spirits first. However, there is the expiration date problem. Does this stuff turn into a pumpkin as soon as it reaches the "best by" date? Thermatru has given me 2 different answers the 2 times I've called (guess I should call again?).
Sikkens Cetol D&W requires 24 hours between coats (OK if Monday and Tuesday are sunny as well), but brochure just says "contact Tech Support" about prep for fiberglas. I'm worried about maintenance. It's supposed to last 2-3 yrs on southern and western exposures, 3-4 yrs north and east. I have west-facing door but a 7ft deep front porch, the late afternoon/evening sun gets intense (esp. on bottom of door) in the summer, rest of the year not bad. So maybe I'll get 3 years. But then what do I have to do to recoat it? Sand it? Strip it?
Which would you use?