Re: how cold it too cold to fiberglass?
so if i get a 40 degree day and use heat lamps i should be good?
Well, that depends on a lot of variables. 40 degrees may be pushing it. And what type of resin are you using?
If you use shop lamps to provide heat you still have to start out with resin at room temperature, so store it in the house for several days prior. Also, before you start spend some time checking out your lamp placement to make sure that ALL areas of the work will be warm enough, but not too warm.
Don't just jump into this without taking some time to make sure you've got all bases covered. If any portion of your layup isn't up to temperature it's not going to cure properly, be very careful about that. Also, it is possible to get the layup too hot, that can be just as bad.
Finally, guess how I know about what can go wrong doing this ..... Yes, I've screwed up a few parts along the way.