I completed two coats a day, one in the morning and one at night.  Rough up with scotch bright pad between coats. sand prior to the final finish. Some will dissagree and sand between each coat. It depends on the vessel, use, and owner.

Your best advice will be found on the label. Note that curing time varies widely depending on temperature. If you want a nice finish, wet sand between each coat and wipe down with brushing liquid. For a clearer, harder, longer-lasting, and much easier to apply finish, switch to marine urethane. -Wes

I'm looking forward to trying Le Tonkinois #1 varnish after I have used up the other varnish that I have on hand. Only 8 hours between coats. It is formulated from Lnseed Oil and Tung Oil. Four coats should be more than enough. I'll be getting some of their Purified Linseed Oil for non-epoxied / non-varnished items too.

http://www.solventfreepaint.ca/linseed_varnish.htm Canada

http://www.solventfreepaint.com/linseed_varnish.htm USA

Keith