I have a WD10 with a varnished hull. I am sanding off the varnish and will replace it with the graphite/epoxy mix. Now that I have sanded, the hull is completely gray, with splotches of darker gray where the wood grain does not show through quite as much.
How much do I need to sand to apply the graphite/epoxy mix?
Do I have to remove all the varnish (and how would I know that), or is the sanding just needed to create a suitable surface for the graphite/epoxy to adhere well?