resin won't cure

jl_photo

Petty Officer 2nd Class
Joined
Jul 30, 2007
Messages
108
I cut a hole in my deck to run cables and decided to paint the edges with some fiberglass resin I got at lowes.

the resin cures normally in the cup and on the brush but will not cure on the wood. (3 days later still sticky)

I mixed enough hardener.

I have had recent success with this can of resin on a different part.

the wood was dry.

temperature here in houston is in the 60s
 

tallcanadian

Captain
Joined
Sep 7, 2006
Messages
3,250
Re: resin won't cure

unless there was something on this area, such as oil or something else. that's the only thing i can think of.
 

supercab78

Petty Officer 2nd Class
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Sep 6, 2004
Messages
158
Re: resin won't cure

I think the resin will stay tacky on the top surface unless a additive with a wax in it is added to the resin when mixing up. Use some sand paper or DA type sander to knock the tacky surface off. It should be set up under the tacky surface. If you put a hardner in it, even a small amount it should set up. I went light on hardener once to have more working time and since it was cooler outside it took alot longer (days) to set up and it was tacky on the top surface.
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: resin won't cure

There are a couple of possibilities.

Some woods have resins and oils in them that will inhibit the cure of polyester resin and it takes another coat to help it get hard.

You didn't mix the catalyst in well enough, this is common and is why you may find sticky areas on the large chunk you pop out of the mixing container sometimes.

The resin on the wood is just too thin to cure, there needs to be enough mass for the chemical reactions to take place and if the air temp was a little cool, it may stay soft.

Having no wax in the resin will let the surface stay sticky even if it does cure well.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,105
Re: resin won't cure

You may cover the resin with a piece of saran wrap to assist in it's curing
 

wire2

Lieutenant Commander
Joined
Jun 25, 2007
Messages
1,584
Re: resin won't cure

Put a heat gun, heat lamp or even a flood lamp on it for 30 minutes, at a distance that it will get up to 130-150?.
Then leave it alone for 1 hour. If it's still sticky, you were a bit light with the hardener, or didn't stir long enough.

How old was the resin?
 

drewmitch44

Lieutenant Commander
Joined
Jun 26, 2005
Messages
1,749
Re: resin won't cure

Was this the elmers resin that they sell at lowes with hardner? Just wondering because ive used it a lot with a bit less hardner than prescribed but it always hardenes for me sometimes takes longer because of the little ammount of hardner i use, but i need that working time at times.
 

Prairie Bouy

Cadet
Joined
Jul 31, 2006
Messages
19
Re: resin won't cure

Found this same problem when I modified a 14' tri-hull into a duck hunting boat. The sticky coating is similar to an amine blush with epoxy. I exhausted a lot of sandpaper and manufacturer tech support before finding out, from trial and error, that acetone soaked rag cut through and lifted it. Was able to sand without loading up the paper after that.

But if it's like amine blush from epoxy then just plain water will work. Might be worth a try before using nasty acetone.

Hope that works,

Al
 

domains

Banned
Joined
Oct 19, 2007
Messages
90
Re: resin won't cure

Once i used tigar hair hardener instead of clear liquid hardener took like 2-3 days
 
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