View Full Version : softening resin

6-Oct-09, 09:16 PM
does anyone know of any substance that might soften hard resin

i made the mistake of allowing a student to use my gel coat spray gun - it looked like he'd cleaned it properly until i came to use it and there's solid resin inside it - any suggestions other than don't let other people use my gun



7-Oct-09, 05:20 PM
Have you tried acetone Tony, it pretty much softens anything. Good luck.

7-Oct-09, 05:28 PM
I think you will find that resin still sets in acetone. Try not cleaning your brush properly and see how it clogs up, even when immersed
Tony I think you have a problem. I have yet to hear of anything that will do the job.


7-Oct-09, 08:14 PM
thanks stu, tried acetone and if you've never found anything Kip then i'm sure there's nothing out there

we used to set fire to the old washer type rollers, the guns are usable so i'll not risk that yet


Paul Fitz
8-Oct-09, 01:18 AM
There is a proprietary solvent sold under the name 23-EpoxSol in the USA and just EpoxSol in the UK/Europe which claims to be effective, particularly if heated in a bath to about 20-22 deg. It does not damage aluminium or bronze. I did a quick google search but could not locate a source for small quantities. You might have better luck.


8-Oct-09, 05:46 AM
Sounds to me that there is only a little bit clogging the hole, have you tried giving it a smack with a hammer, the vibrations should shatter the hard resin and lots of little bits should come falling out. This however is a last resort before throwing it away, I might not work and I do not want to be responsible for your loss. I do that with my mixing stick, works great. Gut on a gun, not sure.

8-Oct-09, 11:55 AM
does anyone know of any substance that might soften hard resin

yup. Crash it into catch netting. Softens it up a treat.....


8-Oct-09, 08:18 PM
styrene! if you can get hold of it, will probably be the only thing that will break down hard resin. acetone wont work!

You used to be able to buy styrene in a can, to paint onto a repair section on a boat hull, it would soften the old resin, so a repair would take. give Cornish Fibre Glass supplies a call.

Paul Fitz
9-Oct-09, 04:21 PM
Styrene has no apparent affect on cured resins. It is not a strong solvent (although it does promote corrosion in copper and copper alloys). It is sometimes recommended to "reactivate" gel coat during repairs of light scratches. *If* this works, the styrene would only act on the outer molecules of the cured resin surface. No good for Tony's problem.

17-Oct-09, 08:00 PM
If you find anything, loads of GRP company's will bite your hand off..

I made the mistake of forgetting to clean a Gel/ catalyst mixer pipe put on a spray gun when i was a laminator...

Cost me a verbal warning, and a day spent cleaning all the spray guns :(.. never did it again though...

Once resin has cured, thats it... :(

We were looking for something similar to break down potting over pcb,s some years back, still haven't found anything, (not that it matters now;))

Of note though, there are systems out there for recovering acetone / so it can be reused. its not as solvent loaded as the virgin stuff, but if you use acetone on a large scale, can save some money