On Jun 20, 12:23 am, "Lew Hodgett" wrote:

Just curious, how does the door manufacturer finish a F/G door?

Gel coat, raw glass, paint primed, paint primed and finished?

There are a few that sell them finished, but less and less. The
prefinished doors are too easy to damage in transit, and by the folks
that sell them.

So (like Thermatru, Jeld Wen which are a couple sold around here) they
sell finishing kits. The kits have a tiny (but good quality) can of
stain, and a water based poly with their respective names on it. The
stain is great, but the top coat isn't.

Currently, no one in town sells prefinished doors unless they are
solid colored. In that case, one of the doors I saw a few months ago
had a dark brown gel coat and from looking at the edges it was
probably a colored resin as well. The homeowner told me it came in a
bark brown, hunter green, and merlot.

The fiberglass doors I have finished have some kind of strange "paint
grip" type of finish on them. It isn't a good marine grade gel coat,
and it isn't UV resistant. It isn't smooth, but it isn't rough,
either. When it isn't finished, it will hold up for a year or so,
then the finished powders, and you are screwed. Whatever that stuff
is (mold release?) it isn't made to be left in the raw.

But if you clean it and finish it right away, it seems to do well, but
only with solvent based finishes. No matter what they do to the
surface, waterborne just doesn't stick as well. The stuff they send
with the door kit I usually toss. I don't know whose product it is,
so I won't use it.

As a sidebar, I have gone to many client's houses that have steel
doors installed, and they thought the priming was the protective
finish! Surprisingly, it does quite well, and a good cleaning and you
can start finishing if there is no rust. I have finished doors that
have probably been installed for 2 - 3 years with no adverse effects
to the top coat of paint.

Robert