> Can anyone tell me a little about thixotropic agents. I laid up a hull
> yesterday and for some reason, most of the resin ran into the bottom. I
> can't figure out why since it never did it before (I've laid up about 15
> boats without this happening).

> What are some of the agents and what are the advantages and disadvantages
> of the different agents?

You generally do not want to use thixotropic agents when wetting out the glass. They impede the ability to wet out the cloth, weaken the layup, and if you want to leave the boat bright, they make the layup cloudy.

Your problem probably has more to do with how much resin you put on, than with how viscous the resin was. Too heavy a coat can sag even with alot of Cab-o-sil in it unless you thicken it up to peanut butter consistency.