Fiberglass Resin not setting up.

[creynolds]

We've been trying to patch some figerglass panels the last couple days and have been having major issues with the resin not setting up. Initially thought there wasn't enough activator so we added more and still didn't get any results (it's being mixed per instructions). After two days there's still spots that are tacky. The work is being done in our shop with the heater running so I don't think it's to cold at the time it's being applied. As far as material goes we're using a generic Auto Zone F/G patch kit. I don't know much about fiber glass but I do have experience with automotive painting. Is fiber glass similar to painting in regards to needing proper activator/reducers for certain times of the year (temperature)? The strange thing is the container with excess resin is setting up just fine, which leads me to think that there's a contamination problem. However the surface has been prepped properly. What am I missing here guys? Micah, Bink, others......any suggestions?

[redmist]

Sounds like possible water contamination.

[TNT race photo]

epoxy or polyester? you may have the right amount of mekp but you didnt mix it well enough.You cant sand laminating resin if thats what your doing,you have to mix up a batch of sanding resin using a surfacing agent.If you dont have surfacing agent try using a thin coat of bondo. TIM

[creynolds]

It's Polyester resin. The shop has been heated but it's not as warm as I'd like it to be. I worked a few other areas today with long strand kitty hair and it was slow to set up also. I ended up setting a heat lamp in front of the worked area and that definitely helped. The weird thing is some areas of the truck will set up pretty quick and others take for ever (still using the same batch of resin). I'm guessing at this point it's just to cold as the heat lamp areas are much better.

[The Desert Shop]

How old is the resin? It may be bad. Too cold can do it but if you put a heat lamp to it and it's still tacky after a few days, I would say not enough MEKP or the resin was bad. Try mixing about a cup of resin with about a 1/4 cup of MEKP, it's called a "hot batch" and brush it over the repaired area, that should dry it, just remember to pour that new batch or resin in a bucket of water or add water to it as it will start on fire or put off the worst smell ever.
Good luck!

[creynolds]

Thanks for the tip Desert Shop. I just recently started using the heat lamp so the initial areas never got that. I'm sure the lack of heat lamp is probably what caused them to take so long to set up.

[TNT race photo]

styrene does go bad the autozone stuff sits a long time,we work in 60 degree temps in the winter thats as low as I would go,a hotcoat with surfacing resin brushed on will set off tacky laminating and is easy to sand, when I do body work long strand bondo then shure form then smooth bondo then fine sand. big areas wet out mat and roll it grind it smoth then bondo fine sand.

[randy s]

get your fiberglass, resin and hardener at west marine. does'nt sit around long. you prolly had old, bad stock. when you opened the container the resin came in, was there any gel starting to build up? cold does'nt help either.