Arctic alumina adhesive didn't harden?

I used some arctic alumina adhesive and it didn’t harden even after sitting overnight. It just turned into this rubbery material that is easy to peel. Did I do something wrong? I mixed as close to equal parts as I could get.

could be old, i had some that was over a year old that didnt completely harden

Perhaps you did not mix it well? It will not get rock-hard but still pretty stiff, not rubbery. And it should stick very tight to many materials including metals.

Sorry, I’d guess that you didn’t mix properly or didn’t mix the right proportions. The epoxy normally gets too stiff to apply in a matter of two minutes after mixing ( about 30C ambient temperature here.) I normally put one blob of Part A down then a very similar size blob of part B next to it then mix. Try not to mix too vigorously because you DO NOT want any air bubbles getting into the epoxy. Air is bad.

I put the same sized blobs and mixed well. I’m guessing it was just old. The leds are stuck well but I’m sure I could pull them off easily. I wonder if I could just put some gorilla glue around it to make it secure and just leave the thermal adhesive to transfer the heat.

Don’t bother with the gorilla glue. If the star isn’t going to fall off, then you’re good :slight_smile:

Oh it’ll fall off alright. It’s going on a cammed out paint shaker.

The adhesive finally hardened, it just took a couple days. I’m not sure if that’s normal it not.