Hi, I recently bought a 5k tub of epoxy moulding paste and hardener as part of an order.
When I opened the tub to use it today the paste was rock hard. I had already coated my parts with the epoxy tooling gel coat so I cut some of the paste out with a knife to attempt to use it. I thought the hardener may soften the paste to enable me to use it. After about 15 minutes of mixing I had to use the paste as the gel coat was setting. Even though I had worked the paste it still had hard lumps in it which I’m sure will affect the outcome of the mould.
So, the question is, is there something I can use to revive the paste or do I need to send it back to you?
Just to confirm, I bough the paste & gel coat with their hardeners last week and broke the seal on the paste tub today.
I have previously used your moulding paste and it was very pliable, like paste I suppose. I’m just hoping all my hard work setting up the work piece hasn’t been in vain!
Please advise me of my options,
Regards
Roger

Hi Dodgyrog,

I'm sorry to hear that you have had an issue with the Epoxy Paste. It is quite sensitive to the cold and will crystallise at around 6’C. It is common, particularly during the winter, for the material to be exposed to this temperature during transit where the goods will inevitably sit in a distribution warehouse overnight before they are delivered to you by TNT. During this time, some (and very occasionally all) of the putty may crystallise. To those unfamiliar with this process it is quite strange and it can certainly seem like the material is defective because once crystallised, the material needs to be warmed to a considerably higher temperature than 6’C (more like 25’C+) in order to un-crystallise back into its correct state. This is because the change of state from liquid to solid is highly endothermic (meaning it needs quite a bit of energy going in) to make this happen. To ‘melt’ the putty you need to put quite a bit of energy in (i.e. put it somewhere decidedly warm, not just above its crystallisation temperature). ‘Chopping up’ the crystallised putty as you describe was not the correct way to restore and use the material; I’m not sure exactly what effect this will have on the integrity of your cured laminate.

If you do have any problems then let us know and we can look into this further.

Hi Rich,
Thank you for your prompt reply. I’ll put the paste in a nice warm environment as see how it goes. If I find it doesn’t return to a more fluid state I’ll get back to.
Kind regards
Rog