Lars,

I've had good results with filling gaps after the seal coat has partially cured. Rather than sanding the filled areas, I wiped off the excess with a rag and applied glass right over the freshly filled gaps. Wiping off the excess left the gaps slightly under-filled, but the depressions were easily bridged by resin under the cloth.

Sam

: The blue 3M Quick Release tape works well to mask both sides of the gap. Then
: pull the tape BEFORE the epoxy cures.

: You could try to fill the gaps just before doing the sealer coat, but what
: happens is the unthickened epoxy from the sealer coat tends to liquify the
: thickened epoxy in the gaps and you'll get some bleed out (this is from
: experience). I think the tape is the best way to go.

: As long as you don't have any scratches across the grain there is really no
: benefit to sanding any finer before the sealer coat.