Thickening Polyester with Silica question

[shep65]

thanks guys !it seems to be hardening up .. I was worried there for a little while .. I read somewhere after I did it to be sure to mix the resin and hardner first because the silica absorbs it and prevents an even cure .

[Curapa]

That's right, but I do know of a few people that pre mix large batches without hardener and take out small batches as needed adding harder after with success.

I do not trust that method, but I have never tried it. I've just read that is not advisable.

[Striper80]

I've mixed the silica in before the hardener without issue, but I noted the measurement before thickening. Then I added the amount of hardener based on that level not the level after thickening.

[cterrebonne]

Originally Posted by Curapa

That's right, but I do know of a few people that pre mix large batches without hardener and take out small batches as needed adding harder after with success.

I do not trust that method, but I have never tried it. I've just read that is not advisable.

I mix the harder first then I add the silica. I do that because I never know when I have time to work on my boat and that resin may go bad before I use it.