Eternal debates rages on....
I’m a varnish guy. Valkyrie’s teak rails were refinished as part of a refit in 2011, five coats for hatches and handrails. Once that was completed, one coat at the beginning of each season has been all that’s required.
Handrails were removed and bleached for the refit; the only casualty was one crack that was easily repaired. After sanding with 3M Fre-Cut 220, two coats of Captain’s Varnish were applied before installation. First coat of varnish thinned 25% with Pettit 120/T-10 Brushing Thinner, second coat thinned 10%, Handrails did not straighten and were easily re-bedded/re-installed. After installation, new teak plugs were set in varnish, and matched perfectly after the final three coats of varnish were applied - full strength, or thinned slightly if needed for better flow. After lightly sanding between coats, I do wipe the handrails with rag and paint thinner, and then a tack rag just before finishing. For handrails I use a 1” bristle brush, and no masking tape except for very tight situations, with 3M Adhesive Remover close at hand. Hatches are taken off the boat for finishing. I sand/varnish as the last job on a spring day when I’m leaving the boat, so I’m not losing sailing time. I do use sun-covers, as seen in the photo below, taken during fit-out last season (handrail covers not shown). The dodger, when installed, serves to protect the companionway hatch.
Full disclosure: all the other sailors in our group swear by Cetol.
Headed down tomorrow to get started for this season!!