Hello all, I'm fairly new to the group and am building my first boat.  I've tried to research this question but haven't found anything to help.  I'm adding silica thickener to TotalBoat Performance epoxy for filing screw holes, chips, chunks, etc.  My problem is good incorporation of the thickener, regardless of how much or how little I stir, shake, rattle or roll, I continue to get these little clumps of silica that make pits in the final surface.  Is there a good way to avoid this?