Laying fiberglass in cold weather?

[gearhead231]

Hello,

As it is getting colder everyday it is becoming harder and harder to work on my bike. Ill have to wait till spring to do any paint work, and probably electrical. So I am setting my sights on making a new seat pan soon. I think I have decided on making my new seat pan out of fiberglass. Partly because I am a cheap college kid, and partly because my metal fabrication skills are laughable.

I was wondering if the resin used to bond fiberglass is temperature sensitive? Or should I say, how sensitive is it? The temperature around Iowa is averaging 40ish degrees F. And Its only getting lower.

Am I already too late?

 

[J-Rod10]

It is. The resin I use is optimal at 78°. When it's warmer, it cures quicker. When it's colder, use a little extra hardener.

 

[mathil]

Depends on the resin. There's ones designed to work better in the cold. There should be a temperature chart somewhere that shows cure times at different temperatures with different hardener ratios.

 

[focusinprogress]

Most manufacturer's list right on the product minimum working temperatures. I've laid fiberglass in the dead of winter before under 20*, but I heated the garage/shop to do it and for about an hour after finishing....then set up my halogen shop lamps pretty close to the part to keep it warm overnight to cure because I never feel comfortable leaving a shop heater unattended. You can usually increase the amount of hardener you add to the resin to help it along too.

 

[gearhead231]

I could do that but I am currently lacking a garage....

this is my "workshop"



My buddy is building a house. He's a huge motorcycle guy. Maybe he will let me park my junk in his garage for a couple days.

 

[J-Rod10]

Another thing you can do, keep your can of resin inside. It'll keep it warm. I built a warming cabinent for mine. Keeps it at 80°.

 

[gearhead231]

Ok so hypothetically, I could "warm" my resin and then go outside, lay it, leave it over night, and itd be fine?

 

[J-Rod10]

It'll be fine.

You'll have to warm it when it is that cold out. Otherwise it is like a paste.

 

[J-Rod10]

Wouldn't hurt to hit it with a coat of rattle can when you finish. Cut the air off from it. Will speed the cure time.

 

[gearhead231]

Interesting. Any brands you would recommend? or awesome post suggestions?

 

[J-Rod10]

US Composites is a good source. Solid materials, good price. I like their 249 Silmar. Lay's down nice, is very strong.

 

[J-Rod10]

If you want to do it properly, make your plug, make a mold, then make your pan.

 

[Connie]

I just made a seat pan for my tailpiece in about 40-50 degree temps. it turned out well, kept the resin inside until I was ready. it started to gel up on me about 10 minutes.. it was my first time with fiberglass so I'm not sure if that's normal. took a day at least to fully dry up.

 

[doc_rot]

depends on how cold it gets; also depends on the resin you are using. if epoxy you can usually go a bit colder by buying the "fast" hardener. if using a polyester resin, one that uses MEKP for the catalyst, you can usually add up to 3%. I have found it wont really cure if its under 30degrees, regardless of the type of resin. it gets kinda hard but remains tacky for quite a while. If its small enough, and an epoxy resin was used, I will throw it in my oven for an hour or two at 170. rock solid after that.

 

[J-Rod10]

The poly will cure in cold weather, but you need to seal the part off. Hit it with a coat of Krylon, or something of the sort.

 

[doc_rot]

The poly will cure in cold weather, but you need to seal the part off. Hit it with a coat of Krylon, or something of the sort.

Hmm, ill have to try that next time I use it in the cold; truth be told, I hardly use polyester resin anymore because its so damn smelly!

 

[Bruceski]

Good advice in here. I usually build a "hot box" out of wood or cardboard and use halogen lamps, space heaters, etc. Close to the work to get the resin to kick. Once it kicks you can pull the heat and leave it in a cold garage. I usually wait at least 24 hours if not longer for full cure to be able to sand. If you don't wait for full. Ire it will be tacky and hard to work with.

Here's two pics of a Jetski riding buddy doing a repair to his steering where it mounts to his hood. very tight space so it's hard to do clean work. But it will be strong since its epoxy. Halogen light used as a Heat lamp for quick cure to ride the next day.

 

[mathil]

You can also add an air dry wax to poly resin to get it to fully surface cure in open air. Only has to be added to the final layer of resin you use.