Hi Wayne

This is a classic blush problem!

First sanding does not remove the amine blush at all well and 80 grit evn less. The best method of removing blush I have found is a nylon brush and warm water with an amonia household cleaner. We have one here called 'Handy Andy'. Even a bit of Scrubs amonia in the warm water will do the trick. Next epoxy is rather like concrete it needs time to react and harden. I would not put varnish over epoxy inside seven to ten days.

There is no need to use a grit coarser than 120 when sanding for the initial coat of varnish and then 220 between coats. All sanding should be wet. I leave varnish two days between coats. This all rushes out the window when using polyurathane varnishes as they are chemical bond and require no sanding between coats other than to remove runs etc.

Rob