Tips for good varnishing

[grumpygit]

+1 to most of that, except that I tend only to start rubbing down after two or three coats. After that gentle wet and dry used wet between every coat. The cheapish soft two-tone synthetic bristle brushes are quite good, the all-black bristle no-loss ones are rubbish, and the very best are really good natural brushes.

I use sponge brushes, similar to http://www.amazon.co.uk/Value-Pack-...=sr_1_20?s=diy&ie=UTF8&qid=1361458036&sr=1-20 No picking out wayward bristles and no brush marks. After use I wipe of the excess and put a few drops of thinners on the sponge, then wrap in cling film, this keeps the brush usable between coats.

 

[Rossynant]

Yes I actually wanted to just go via the oiling route (not too bothered about the look) and the online supplier sold me Woodskin. I asked for an oil, he sold me an oil based varnish.

There might be a bit of misunderstanding nowadays, as many different products go around. Some people take Polyurethane varnishes as "classic varnish', for instance.
IIRC Woodskin is midway between oil and varnish, same way as Cetol or even Deks Olje (they sell both oil and
"flexible varnish").

Real, "classic" varnish containes a lot of resin (alkyd now in use) and gives high build, hard finish comparable with polyurethanes, but not elastic, can crack. Still better than polyurethane for marine use, as wood can be oiled first (or first coats may have oil added for some aplications).

For marine use better kind is "Spar Varnish", this is more elastic, has more oil, will not crack when wood works underneath.

Then come those "Wood Finish" treatments having even less resin, like Woodskin. Mostly so little resin in proportion to oil, also some thinners added, that surface remains porous so wood can dry out better, less probability of lifting the coat.

For practical use any such product, i.e. oil/alkyd, can be modified to suit one's needs by adding oil or diluting with turpentine.