Epoxy wood before re-varnishing?

[Tim Good]

OH GOD , a varnish question is akin to an anchor question, theyll all be out from under their rocks now ! - Take a look at coelan , it works for me - its not cheap mind you, Ken Howles teak merchant in Poole did a teak yacht from scratch called cariad , completely coated it in the stuff , lasted for donkeys years as has mine

Funny... my last boat was called Cariad.

Anyway assuming I expoxy prime my wood first this time and then varnish... when my varnish needs re doing again in say... 2-4 years... will it be a nightmare? I.e. will I not then be able to strip and sand it easily... or is the point that I wont have to strip it right back and sand as the wood will not have stained or absorbed water?

 

[lw395]

Funny... my last boat was called Cariad.

Anyway assuming I expoxy prime my wood first this time and then varnish... when my varnish needs re doing again in say... 2-4 years... will it be a nightmare? I.e. will I not then be able to strip and sand it easily... or is the point that I wont have to strip it right back and sand as the wood will not have stained or absorbed water?

If the epoxy is not breached, the varnish will eventually fail and peel off. That's easy to restore.
If the wood gets deep gouges which go through the epoxy, then water is allowed in for a while, it can be a nightmare to get it immaculate.
If the varnish fails and you leave it unvarnished for a (longish) while, the epoxy may go a foul yellow tinge, which you can only cure by sanding back to bare wood. Not great on ply.

If the structure is such that the epoxy does not seal all faces of the wood, or cracks through stress, letting water behind the epoxy, it may be worse than varnish. It's tougher to scrape back.

 

[ccscott49]

There is a system, which uses an epoxy saturator, PU 120, I think, then a two pack polyurethane varnish over the top, 360, I think, when home I will post the manufaturer, it come from France or Italy. Its an excellent system, as long as the substrate does not mone and crack, then the water gets uunderneath and its a nightmare. I used Coelan on my masts, 14 years ago and have just re-done them last winter, yes its expensive but I didnt touch my masts in that time and in most places it was a sgood as new, albeit without much shine, where it was damaged it needed removing, an easy job as it peels off, with a bit of help!!! I am using it on my toerails, bulwarks etc, not on the cabin or wheelhouse as thats conventional epifanes, seven coats of "rapidclear" fololowed by four coats of "high gloss". Works for me.