Re: Using epoxy without hardener?
It wasn't the mix that did that. It was the temperature and the can shape.
If you want epoxy to have a slow kick off, put it in a big wide tray or mix a small batch. Always match the part A to part B ratio to what the manufacturer recommends. You can also cool it with ice or keep the stuff in a refrigerator, but that can affect curing too.
If you put in too little or too much hardener, you won't get a proper cure. That's it. It won't explode or cook because of that. If you put in too little hardener you sometimes won't even get the stuff to harden. But if it does harden as ondarvr says it won't be full strength.
Neither will "cooking" (heating) epoxy mixed with too little hardener help things... if you mixed it ok and it's just been too cold to cure sometimes it'll help it harden, but if it's short on hardener all it will do is make it more runny.
Those tricks work for poly resin, not epoxy. Bottom line, mix the stuff at the temp and ratio recommended by the manufacturer. If you don't have enough working time, switch to a different epoxy.
The USComposites stuff I use in the "medium" speed is comparable to West Marine's "slow" speed... it varies from mfgr to mfgr.
Erik