Thread: Tung oil finish for walnut brush and scales?

I've got a question for all you wood finishers.
What I've done so far: I've turned my first project and it happens to be shave brush handle in walnut. I've decided on a pure tung oil finish (from Rockler) since I've never tried it, I want a matte finish, doesn't have fumes, was supposed to be waterproof. First coat was 50/50 mineral spirits to tung. I then rubbed on a light layer of that, let it sit 15 minutes, wiped off any extra and rubbed it in with my hands (as per the instructions). The other three or four coats were straight tung oil. Now, I've let it sit at least a week. I did a quick test of water droplets to see if it was waterproofed and it failed. So I got some Helmsman spray urethane and did two very thin coats. It doesn't seem to be drying. I can literally scrape it off with my palm.

My questions: Can I truly get a waterproof seal with tung oil? Should I let the brush sit in vat of it for a couple days (because maybe my coats were too thin)? Can I put urethane right on top of dried tung oil?

That was a long post. Thank you for reading. As repayment for information I'll post pictures of the handle (and eventually scales).

Scrape it all off and start again...

One, I would not use Tung on a brush, there is a big difference in getting the scales wet and then drying them off, and SOAKING that brush in hot hot water, then having a damp brush for hours after the shave....
I will argue till I am blue in the face saying that NO tung oil finish will hold up to that for long....

OK now what to use, first clean it off, use acetone let it dry, use acetone, let it dry...

If I were doing it, I would use a sealer first, then the most water proof coating I could get on there...
Or maybe just use pour epoxy and be done with it...

I was worried that would be the case. Well, sometimes you try "new" things and you fail. Thanks for the advice Glen. Guess what I'll be doing tonight.

My experience has been that getting wood wet isn't what hurts it, its drying it and the fungi that it can develop. I have a walnut back scrubber that has been soaked every night for the last 5 years and still going strong. No cracks, no checks, no nothing.

Tung oil is not the best finish for brushes, but it's still a lot better than no finish at all.

IMHO the best finish for brushes is a hybrid oil/topcoat. an example of such a finish would look like this:

1. oil, several coats, burnish between coats
2. lightly sand
3. shellac wash coat
4. polyurethane (or other waterproof topcoat)

By using oil and then topcoating, you greatly reduce the chance of water infiltrating through the topcoat (either physically through cracks/scratches/dents or by means of vapor transfer, which is what happens when liquid water is allowed to sit on it)

I have had pretty good luck with epoxy on brushes.. it's kind of tricky though on a 3d surface like a brush though. So far it is my favorite of all of the finishing options I've tried.

Originally Posted by floppyshoes

Tung oil is not the best finish for brushes, but it's still a lot better than no finish at all.

IMHO the best finish for brushes is a hybrid oil/topcoat. an example of such a finish would look like this:

1. oil, several coats, burnish between coats
2. lightly sand
3. shellac wash coat
4. polyurethane (or other waterproof topcoat)

By using oil and then topcoating, you greatly reduce the chance of water infiltrating through the topcoat (either physically through cracks/scratches/dents or by means of vapor transfer, which is what happens when liquid water is allowed to sit on it)

Not to discount gssixgun's advice, but I think I'll give floppyshoes' method a shot. I really like the look of tung oil and i want to see if I can get it to work. Since shellac works with oil coats and poly I think this will be my road of travel this time. Worst case is it doesn't work and I have to take it back to an acetone bath.

I would do epoxy but the person I'm making this for doesn't want a shiny finish. Granted, I could cloud the resin haha.

Dan is Da Man when it come to wood finishing, there is no doubt...

Originally Posted by claytor

Not to discount gssixgun's advice, but I think I'll give floppyshoes' method a shot. I really like the look of tung oil and i want to see if I can get it to work. Since shellac works with oil coats and poly I think this will be my road of travel this time. Worst case is it doesn't work and I have to take it back to an acetone bath.

I would do epoxy but the person I'm making this for doesn't want a shiny finish. Granted, I could cloud the resin haha.

Make sure the oil's cured first, or nothing will adhere properly, not even shellac. If it's not curing, you'll have to remove it with acetone as glen says. My method assumes the oil is cured before you go on to the topcoat.

Are you not rubbing it off enough? Are you not leaving it enough time to cure between coats? If it's a "Tung oil finish" then there are likely dryers and maybe even varnish in the mix, so if it's not curing in a few days there's a problem.

Originally Posted by floppyshoes

Make sure the oil's cured first, or nothing will adhere properly, not even shellac. If it's not curing, you'll have to remove it with acetone as glen says. My method assumes the oil is cured before you go on to the topcoat.

Are you not rubbing it off enough? Are you not leaving it enough time to cure between coats? If it's a "Tung oil finish" then there are likely dryers and maybe even varnish in the mix, so if it's not curing in a few days there's a problem.

Pure Tung and I let it cure for a while. I was rubbing the heck out of the the oil applications the first trip around. I wasn't sure how to tell when it was fully cured but I did the next application when it didn't have an oily feeling, didn't smell really strong of tung oil, and overall felt dry/had a slight sheen. I'm guessing I gave at least 24 hours between coats and then about 3 days on the final application.

Last night I sanded down to the initial coat of tung oil and reapplied. I went a bit heavier on the application then I did the first time. Rubbed it in with my palm, let it sit for 10 minutes, then rubbed it dry with a cloth. I'll give it 24 hours, hit it with sandpaper, and repeat.