Workers Of Wood

If you can't spray or your finish is not suited to spraying, wiping on varnish is a good choice.

First some basics:

• Polyurethane is a varnish. It's one of the three common resins used in making a varnish and the most ubiquitous. The others are phenolic (found in Waterlox varnishes) and alkyd (found in a decreasing number of products, Cabot 8000, S-W Fast Dry Varnish, McCloskey's Heirloom, P&L 38 (RIP))

• This is probably one of the most mis-leading labeled products out there. Most will say anything but 'wiping varnish' See Flexner's article for some samples

• You can easily make your own from your favorite brushing varnish.

• Almost every magazine out there has an article on wiping varnishes, as do many YouTubers. Here is a good one (long read) Bob Flexner's methods

I like wiping varnishes when I need to varnish something, particularly when there are a lot of joints such as in a chair, bed, or table. It eases getting finish in all the concave corners.

The method I use is one spec'd by Steve Mickley, and I'll paraphrase.

Make your own wiping varnish by taking regular (brushing) varnish and diluting about 50:50 with mineral spirits. Unless it's gloss, stir once in a while during and before application as the flatteners will settle out much quicker in this thin mix.


First day:
With a lint-free cloth, wipe on the varnish. Steve said, "Like the bus boy at Denny's wiping a table." That is, a very light coat.
Let the varnish get tack free (the "pinkie test") that depending conditions should take a few hours. Then apply a second coat.
Let the varnish get tack free (the "pinkie test") that depending conditions should take a few hours. Then apply a third coat.
Ideally, unless you start late in the afternoon, you can get these three coats on in a day.
Let the varnish dry overnight or longer. Hang the cloth to dry (don't leave wadded up in a heap)

Second day:
Lightly sand the dried varnish with P400 sandpaper and/or scotch-brite pad.
If you wish, you can use a less diluted mix, but it will tack up faster.
Repeat the first day's schedule. Let dry overnight again.

Third day:
Repeat second day schedule.

So now you have 9 coats, but because it's thinner, it's equivalent to 3 or 4 brushed on coats. And it's taken the same three days and two sandings as a brushed on finish, it takes about the same amount of time because it's faster, and no brush to clean up and if you've done it right, no runs, drips, or light spots.

You can optionally follow up with whatever you normally use for a brushed on finish. You can polish with a paper bag (Kraft paper), hit with steel wood and wax, or whatever.

Thanks for the writeup, Keith...

The article by Flexner is very interesting and easy to read...

When I installed my unfinished hardwood floors a very long time ago I used a product called "Gym-Seal"...have never been able to find it again. It has lasted, hasn't yellowed and hasn't even scratched under the dining room table chairs...no doubt it must have been the most VOC-toxic product out there but, WOW, I wish I could get my hands on some now-a-days. I probably killed half of my active brain cells on that project...

Nickp wrote: ↑Thu Dec 17, 2020 6:25 pm Thanks for the writeup, Keith...

The article by Flexner is very interesting and easy to read...

When I installed my unfinished hardwood floors a very long time ago I used a product called "Gym-Seal"...have never been able to find it again. It has lasted, hasn't yellowed and hasn't even scratched under the dining room table chairs...no doubt it must have been the most VOC-toxic product out there but, WOW, I wish I could get my hands on some now-a-days. I probably killed half of my active brain cells on that project...

Years ago when the community refinished the oak floors in our community hall they used some German made product that sounds similar. I only worked on stripping the old finish down to bare wood so I don't know what it was but no one was allowed in the hall for several days after. Makes you wonder what the people applying it were exposed to.

Good article Keith. I've tried wiping varnish on before but never thought to put that many coats on.

@Nickp
Before waterbased poly they used to use a "Swedish" finish that was the wickedest finish I have ever been around, but it held up forever. It may have been a 2 part mix.
I think it was called "Glitse" and was acid based.
@kmealy
Can water based urethane be wipe on?
Herb

Can water-based urethane be wiped on?

Never tried it, but I think not. It dries very fast and you may upset the balance with just pouring in 50:50 water. Water-borne products are a delicate balance of 7-10 ingredients. Oil-based products have a much wider range of compatibility with varnish, oils, and thinners. I have a product that is similar to "butyl cellosolve" (Ethylene glycol mono butyl ether) that might be a good extender, but I don't use it for that so not sure what the ratio would be. My stuff is made to slow down w/b stains.

Though Mohawk has/had a product that was in their touch up line that was a "water based padding finish." It was designed to be wiped on a repair or touch up. I used it a couple of times, but it was never in my usual process. Almost all commercially finished furniture uses a lacquer of some sort, so Lacquer is a good compatibility for repairs. It was very low viscosity, so I'm not sure it would build on its own.

I have used clear acrylic diluted 50/50 (with water) for a brush on finish over shellac, it dries fast,giving me easily 4 coats a day, and doesn't run or leave brush marks.
Herb

Good info. Never tried that.

The w/b finishes I've used dry quickly. Usually an hour or two I can sand and recoat.

Michael Dresdner mentioned that at a presentation he gave for our club. Also he said that a drop or two of latex paint can tint water based finishes.
Herb

A few years back I tried the oil based 1 Hr Varathane. It was terrible. It might have been okay to spray but it was horrible to try and brush on. You couldn't go back and try and cover up brush strokes because it was drying so quickly. It made me think back to the paints I used as a teen and they were no problem at all to brush on. They also took 16 to 24 hours to dry enough to recoat. Thinking about why that made a difference It dawned on me that the slower drying time gave the finishes longer to self level. The short drying finishes skin over so fast that they don't have time to level.

A couple of years ago my wife asked me to make her a nightstand and she wanted it painted white. I went to Benjamin Moore and asked for the slowest drying enamel they had. When I sprayed it I was a little out of practice and got a few sags from spraying it on too heavy but because the paint had a 16 hour drying time it leveled out and saved me from needing to redo it.

I had the same problem as you, that is why I started to thin the urethane, that solved my problem. Also it seemed like urethane seemed to smooth out months after it was applied.
Herb