: I've nearly finished my Guillemot and have just started varnishing, problem
: is the varnish will not dry no matter what I do!

Well, it is a bit late now, but the thing to do was to thin the first coat, or mix in an additional drying agent. Here is why:

Varnish is a resin dissolved in a mixture of solvents. Some of the solvents evaporate quickly. Other solvents do not evaporate, but they thicken, coagulate or polymerize in the presence of oxygen. The evaporation of the lighter solvents thickens the top of the layer of varnish you have applied so it won't run. Unfortunately this creates a "skin" of jelled resin which sits on top of any liquid varnish which might be there. If you put on a very thin coat then the only varnish on your boat is just barely thick enough to create that skin. If you put on a heavy coat, then the skin forms on top of the remainder. This skin seals off the surface. It greatly reduces the opportunity for the remaining solvents to evaporate. and it excludes oxygen which would help the materials polymerize.

When applying varnish to bare wood the first coat has the opportunity to soak into the pores of the wood. Excess solvents are absorbed into the wood, and dissipate over time. (sometimes decades!)Air in the wood pores helps the polymerization process. When applying it over an impervious
base such as epoxy resin, the only way those excess solvents can escape is out through the surface. It will take time. Just be patient.

The second and subsequent coats will dry much faster. The underlying layer of hardened varnish will soften due to the action of the solvents in the next coat you apply. This serves to bond the two coats together. It also absorbs some of the excess solvents. With more of the solvents disappearing, the second coat appears to dry faster. Actually, though, you have slightly softened the first coat, and to get complete toughness you'll need to wait until those solvents have worked their way out.

I usually suggest doing repairs and varnishing in the fall at the end of the paddling season. That way the varnish can harden over the winter storage.

: I thought I would use a top quality brand, so I spent a small fortune buying
: "Epifanes", top knotch stuff.

It is good stuff, so let it go longer and more of the solvents will work their way out.

Artists who use natural varnishes to protect their oil paintings frequently mix in a copal mixture or a material called Japan Dryer. These help the oils and resins polymerize a bit faster. For our purposes, though, it works best to just thin the first coat with about 1 part of solvent to 10 parts of varnish. Stir the mixture and let it rest overnight in a tightly covered container and when you apply it you'll have no problem with trapped air bubbles.

Sometimes the best part of boatbuilding is the opportunities for relaxation. Drying varnish is Nature's way of saying: "Slow down". Take a few days off from building. Find an excuse to take the family out for a nice dinner, and tell them the boat is the reason for the adventure. They'll enjoy the boat even more after that.

hope this helps

PGJ