Watco danish oil on trim in heated and unheated shop walls

[Tim Monroe]

I tried different clear coats on scraps of Radiata pine I'll use for window/door trim in a shop. I wanted to find one that darkened reddish brown heartwood and didn't yellow or darken the pale sapwood too much. Two water based General Finishes clear coats both resulted in least amount of contrast between heartwood and sapwood. Waterlox darkened sapwood more than heartwood so not much contrast. Home brew oil/varnish (1/3 BLO, 1/3 MS, 1/3 oil varnish) not much contrast, sapwood darkened and yellowed. Regular shellac was also not much contrast and second coat started yellowing sapwood.

Zinsser dewaxed Sealcoat looked good with only one coat. Second coat was a light sheen on some of the surfaces and third coat was a gloss surface (even after rub-out) that I wanted to avoid. To me, the best looking, highest contrast finish was Watco Danish oil.
So, what are problems using Watco Danish oil on trim in a shop heated in winter, unconditioned open windows in humid summers, and some window stools exposed to sunlight through east and west windows. Also, could Watco hold up on exterior side of partition wall, that separates shop from parking area in unheated northern Ohio garage.

Thanks for your help,
Tim

[Jim Becker]

Not likely any issue...homes only got air conditioning "recently" in historical perspective and finishes like Watco are just varnish, oil and a solvent.

[Tim Monroe]

Thank Jim. I don't have wood surfaces treated with Watco a few years ago, to see how those surfaces age. From what I've read, I'm expecting to need to reapply Watco from time to time. I'm not sure if that's because surface will attract a lot of dust/grit/dirt or maybe because surface will noticeably dry out? I guess I'll just try it in the heated shop and even on the wall trim on the unheated parking side of shop, and just keep an eye on it to learn how it holds up.

[Jim Becker]

I do not see why you would have to re-apply Watco periodically. It's a a finish that cures. It will not be in the weather if it's inside the shop. It's just "varnish", but the "Danish oil" version with a little oil and spirits added to make it penetrate and be easy to apply. It's not like mineral spirits which never cure and gradually dissipate. If you put an enormous number of wiped on coats, you'll have a visible film finish.

[Tim Monroe]

OK. I appreciate your help Jim.