: My kayak is in need of a serious rehab. I would like to sand off
: most of the epoxy and give it a few fresh coats to fix some deep
: scratches and dings.
: My question is: do I need to sand all the way down to the weave of
: the glass? Is it enough to just get rid of most of the varnish
: and scuff the old epoxy? What about deep scratches and dings?
: Will fresh epoxy stick to small areas of cured varnish?
: Thanks,
: Matthew

If you're really paying attention, old varnish is yellowish when you sand.
Epoxy is whitish when you sand.

If you did a good job of applying epoxy when you built the kayak and it isn't "resin heavy", then the epoxy layer won't be very thick!!

More elbow grease + finer sandpaper to avoid going deep into the weave.