Fiberglass resin doesnt want to get hard... Options

[Andyrew]

Workin my f/g flares.. Laying some fiberglass and the resin doesnt want set.

Instructions say it should set in 20 mins..

Its been 2 hours, and its still wet.

Some of it is hard, and some other stuff is hard as well, but most of it is pretty bad.

Any suggestions? Im going to let it sit over night and see what it does.

Andrew

[sj914]

Did you mix the hardener/activator thoroughly?
Temperature affects cure time as well.

[m.monge]

did you put enough hardener in the resin. and if you did, did you mix it well enough? other than that all I can think of is maybe it's too cold/not enough sunshine to cure yet? I cant think of anything else. Good luck.

[alpha434]

Yeah. I guess climate control is REALLY important for that stuff. Humidity affects dry time

[tdgray]

My guess Andrew is that you either did not mix the hardner well or you put in too little or too much. Yes too much will make it not react appropriatley as well.

If all else fails give it a viagra (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

Strip it out and start over.

[McMark]

It's freezing, yo. Put it in the sun or in the house with the heat cranked up (smelly). (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) Or just wait a long time.

[spare time toys]

Heat lamps (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) We use them on flap repairs to speed up cure times when we gotta fly in the AM (IMG:http://www.914world.com/bbs2/html/emoticons/beerchug.gif)

[tdgray]

QUOTE (McMark @ Jan 6 2006, 07:16 PM)

It's freezing, yo.  Put it in the sun or in the house with the heat cranked up (smelly).  ;)  Or just wait a long time.

It's freezing in Modesto????

Did I miss the bulliten where hell froze over too. (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif)

[redshift]

Bad mix. A test mix should get hot in 5 minutes.

I DO feel your pain. What a farggin' mess.



M

[Andyrew]

Its about 70 where I was working.

I might have used to much resin (I wanted it to dry fast because I was working upside down.. gravity not friend)

I think the resin that I had went bad (or the hardner)

So I mixed another batch of resin correctly and went over the semi hard stuff with it.

I'll come back after work (at 1am (IMG:http://www.914world.com/bbs2/html/emoticons/dry.gif) ) and see if its hard. If its not, i'll strip it out.

No pics.. It will all be posted at once.

Andrew.

[andys]

QUOTE (Andyrew @ Jan 6 2006, 03:31 PM)

Its about 70 where I was working. I might have used to much resin (I wanted it to dry fast because I was working upside down.. gravity not friend) I think the resin that I had went bad (or the hardner) So I mixed another batch of resin correctly and went over the semi hard stuff with it. I'll come back after work (at 1am (IMG:http://www.914world.com/bbs2/html/emoticons/dry.gif) ) and see if its hard. If its not, i'll strip it out. No pics.. It will all be posted at once. Andrew.

If you have a container of polyester resin of unknown age, always do a test sample in a cup first.

It's usually best to start with fresh materials because as you may (?) find, it's a lot of trouble to deal with the alternative.

Andys

[Pugbug]

Resin has a limited shelf life...The cobalt in it deteriorates over time. Always better to use fresh resin.

[dmenche914]

Ditto on the comments about expired resin / hardener, they do have a shelf life.

Suggest if it is not hardening correctly that you will have ot strip it all off, you don't want incorrectly cured resin as a base, as it will propably cause problem later, like lifting or bubbling,

Sorry, good luck

PS be sure you have good ventalation, some of that stuff is none too good to inhale.

Also adding extra hardener (thats what you meant I assume) to speed up the reaction may not be too good a plan. It can speed it up, but, more heat is generated faster, so warping/expansion can be an issue, and often the end product is too hard, hence more brittle and may more likely crack later.

really best to stay within the manufacturers limits on mix, shelflife and temperature.

[Pugbug]

Another safety tip when using the hardener....Use goggles because one tiny droplet in your eye and you will never see out of that eye again...It cannot be rinsed out!

[Katmanken]

Go to a boat supply store and bring an empty milk jug.

Buy one gallon of fresh resin from thier drum in the backand take it home and do it right. Buy their hardner in the fridge too.

Resin is thermoset. Not sure if the new stuff will cause the old stuff to set up. Have tried it with no luck before.

Ken

[Pinepig]

QUOTE (Pugbug @ Jan 6 2006, 07:44 PM)

Another safety tip when using the hardener....Use goggles because one tiny droplet in your eye and you will never see out of that eye again...It cannot be rinsed out!

Yes it can, but acetone doesn't feel very good either.

[Andyrew]

All good advice everyone! The fiberglass was under the fender so I dont care at all if it "lifts".

But I'll throw away the old resin and hardner and use the new stuff I bought this week.

Andrew.

[Dr. Roger]

heat lamp 'till sunrise.

if it aint dry by then, start ripping.

sorry man. but it could have been worse... (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

[Andyrew]

Oh yes, forgot to say, its dry and hard...

Gave it some good pulls and I didnt hear any cracks either. so I think its fine.

Thanks! More advice with working with this junk. erm I mean stuff is welcome! (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

[marks914]

Remember that resin and hardener mixing is a chemical process. The resin cures, not dries. I usually use a little more hardener or MEK than reccomended. Aheat gun can also speed up the process. Test first!
Mark