I thought with an oil base varnish, the oil from the varnish will bond with the teak oil. When I installed my Teak Deck on my swim platform, I laminated it [3/16"] with epoxy, and had to wipe down the teak with Lacquer Thinner and then scrubed with a stainless wire brush followed with more thinner, It's been 4 years an no problems. I just thought with the varnish you might not have to go thru all that. Anyway, thanks for the info...Joe D
You're right. Though it won't hurt, prepping teak for varnish is a waste of time for the reason that you point out - varnish's oil content.
You're also right regards prepping teak to be laminated. Once prepped, my preference is for a two-part polyurethane (I used to buy this from Aircraft Spruce & Specialty decades ago) for mating surfaces run through a jointer. For sloppier joints, I'd use epoxy.
Regards brands of varnish, any by Interlux.
what happens when water gets under epoxy does it come off in sheets