Hi,
I purchased the 5kg pack of Glasscast 50 three months ago and it's been stored in my wood shop. I've just pulled it out of the cupboard and found that the resin has gone hard in the bottle! The bottle of hardener is still fine.
Does the resin have a shelf life or is there a problem with it!
Cheers
Andy Firth 

Hi Andy, I’m sorry to hear that you’ve had issues with your resin; the batch number of your resin/hardener is part of a 3,000kg kit and so I can say with confidence that the resin itself is not faulty however, the GlassCast 10 and 50 resins are extremely sensitive to low temperatures and if the resin gets below 7’C (either in storage or transport), it can crystallise, at first becoming milky and in extreme circumstances becoming quite hard with the process; this does not damage the resin at all and can be reversed by heating the resin in its container with the lid securely in place. However, if the resin is used when it is in this crystallised or semi crystallised state, it could result in potential curing issues.



To reverse the crystallisation, you’ll need to hold it at 40-50°C+ or indeed even hotter for a few hours as it does take a bit of energy to reverse the crystallisation. You could achieve this by sitting it directly onto a radiator, putting it into an oven on a low setting or standing the container in hot water (although you would have to change the water a few times to maintain the temperature) but this will return the resin to its clear, liquid form ready to be used for your project and, when returned fully to clear, it will cure faultlessly.