There are good products out there, but
there are also finishes that are the result of hundreds of years of knowlege acquired by traditional wood workers. I am not as impressed by the dollars companies spend on advertising as I am by actual experience. Too often the advertisers tell you their product is a substitute for the time consuming process called "do it right". The product de jour may be the one your previous owner used, Tony. There are several "varnish restore" products on the market that are mostly acetone, which will sort of dissolve old varnish and oil so you can mush them together with a rag. It's a cheap (except for the price of the product) trick that looks good for a few months. More if you keep wiping the stuff on. Pete Culler didn't just fall off the turnip truck. He designed and built boats for about 40 years before he wrote Skiffs and Schooners. He also built and lived aboard his own designs for longer than most of us have been on the planet. When I was manager of the school of wooden boatbuilding here on Gabriola Island (link below) our head instructor, who trained in his dad's boat shop as a shipwright in England and had his journeyman's papers from a guild that built ships to fight the Spanish armada, used what he called 1-2-3 to make an interior varnish finish that was deep and durable. first coat 3 parts thinner, 2 parts boiled linseed, 1 part varnish (good quality exterior varnish, not spar varnish. It doesn't have to say marine if it's from a reputable company, just exterior) wipe it on with a rag, let it set for a while, wipe off everything you can. This coat seals the wood. Second coat Sand with 220 grit. wipe all the dust off. 1 part thinner, 1 part boiled linseed, 1 part varnish wipe it on with a rag, let it set a bit. wipe it off. The surface will be a bit shiny like a rubbed oil finish. A lot of us would stop here. Sand with 220 grit, then build up the varnish. We would thin the first three coats maybe 10%. Brush it on, then come back with an almost dry brush and brush it out. Let it dry. Really dry! sand lightly with 220 grit. Wipe all the dust off with a clean rag, then wipe with a rag slightly damp with thinner, let it dry, and repeat 7 to 10 times. maybe 400 or 500 grit for the last few coats. Clean and wipe down everything you can reach in between coats. let the dust settle. No fans or heaters to stir up the air. Dust in the air is the enemy of a really smooth surface. Varnish will last for a long time inside. It's the UV that shines through the varnish and breaks down the surface of the wood that makes varnish come loose. Spar varnish has additives to resist chafe from lines and rigging on the mast. Good stuff, but it's harder to get a deep gloss because of the anti chafe additives. Having said all that, most folks wouldn't notice the difference between spar and exterior varnish, and most folks will be happy with a couple of coats of whatever the merchants are pushing this year, sanded with 120 grit between coats.
