The instruction has nothing to do with the actual timing of solidification. We have been using similar products from other companies and there was no problem. We followed the instructions from your company and the product hardened faster than you have written, even though we started on the 30th second. The product didn’t became homogeneous mixture. After it hardened it was full of air bubbles and casting couldn’t be continued! Worst given money ever. And this was a Christmas gift. Thank you for