Fiberglass Coldweather??

bruther · Post by **bruther** » Sat Dec 06, 2008 7:31 am

Does anyone know if you can fiberglass in cold weather?
Thanks
brian

Post by **Jacampb2** » Sat Dec 06, 2008 7:46 am

I believe that most resins are recommended for temps above 50° F. You can get accelerators from paint and body shop suppliers. You can also mix it a little more hardener rich, but that is not recommended as it can reduce strength and will significantly reduce pot life.

How cold are we talking about? I did a bunch of fiberglass work in my shop last year, in 10°-20° outside temps, but I heated the shop during the day. No heat at night though, and sometimes the last coat of glass had still not set up by the following day...

bruther · Post by **bruther** » Sat Dec 06, 2008 8:26 am

I'm working outside and its 34 degrees out........ is that bad?

Post by **Jacampb2** » Sat Dec 06, 2008 8:40 am

bruther wrote:I'm working outside and its 34 degrees out........ is that bad?

Yup. My personal opinion would be to not even try until there is warmer weather, or until you find a way to do it indoors. The resin and hardener combine with an exothermic reaction. It gives off heat, speeding the cure, if the catalyst (hardener) is used up before the resin completely cures (due to it being to cold out), then it may never cure. Then you have a huge mess on your hands. You may want to go to a local paint/body or marine supplier and get a professional opinion (the guy at Autozone definitely does not count), there may be a accelerator or other additive to make it feasible, but I wouldn't risk it. At best you may find something that will help it cure in these temps, but that will mean a shorter working time, and unless you are really good at what you are doing, then shorter working times will mean poor results. You would be better off putting the project off until spring.

Later,
Jason

Post by **Rold Gold** » Sat Dec 06, 2008 8:40 am

Too cold for glass.......IMHO that is. If ya can't keep it warm for the most part, the finished product wont be as good as it could be. See if you can use a buddy's garage for a couple days.......

bretti_kivi · Post by **bretti_kivi** » Sat Dec 06, 2008 10:42 am

if it's not low-temp resin (there are some epoxies that will go off above 5 degrees c), then either the humidity or the temp will get it. You could mix a hot batch with lots if hardener - but this only works if it's polyester. And even then, it might not go off.

fanheater in the car for the 20 mins? how long's it supposed to take? what is it? can you not take a positive form?

Bret

lashlee · Post by **lashlee** » Sat Dec 06, 2008 5:37 pm

I glass outside until it starts to setup then stuff it in my cherokee with the heat on high! After about 30 minutes it has set up enough to add another layer. If I don't need another layer then I do let it set in ther garage over night. If it's a thinner part I would let it sit for at least 24 hours if not longer.

gkitching · Post by **gkitching** » Sat Dec 06, 2008 9:47 pm

How big a piece you doing?

You could always make an oven with a cardboard box and heat gun. I'll do that in normal weather to speed things up. Should work good for cold weather too.

gfunk_nz · Post by **gfunk_nz** » Wed Dec 10, 2008 12:02 pm

Are you using polyester or epoxy. I am making a wheel well sub box for a guy at the moment and although it's warm weather here now I have been using the fast cure hardener which is specifically for use in cold weather. You have to stick to the 5:1 ratio otherwise you will not get the required strength, but even using polyester where you can add more hardener we built a lid for a box in the middle of winter no problems.

I've just had a look on the west systems website, the Z205 fast hardener tht I have been using they say can be used down to about 40 degrees