: How much filling is really necessary after sanding?

: I've sanded to what I think is smooth and fair but there are still a couple
: of 6" gaps about the thickness of a business card but I'm frightened
: to fill & sand because I think I've sanded those areas more than
: enough & I don't want to risk sanding through!!!!

: What are the implications of glassing and epoxying over such gaps?

It is easy to fill gaps the size you discribe.

Fill them with wood.

Take a strip and cut a 1/16" slice off on the table saw. Lay the strip on
a bench edge and sand one edge to taper it with 80 grit and a hand block,
until this edge will fit into your gap. Cut pieces of this gap filling strip as needed
to fill the gap and glue in place. Pare of the excess after the glue is dry and sand
lightly.

All the best,
Rob