Correct way to finish with Tru-Oil?

[GreenWoodworker]

I sanded the top on my old cedar guitar and finished with tru-oil, watched youtube videos and it still didnt look like theirs when done, not sure what the best way is to apply? And i did 4-5 coats, do i just need more? Ive stripped the top on my new spruce guitar and going to tru-oil it soon.

[printer2]

4-5 is just a teaser. Keep going. There is someone at another forum that takes Tru-oil to a high level. I'll see if I can find some posts of his.

[Ben-Had]

I use 10-20 coats when using Tru-oil. If you are doing the whole guitar in it you can pore fill with it as well using a sanding slurry to fill the pores.

[printer2]

Not sure if this is the one but it has been recommended a number of times.

I have a method that was taught ot me by Michael Tobias, its roughly a 5 day process

once the guitar is well sanded to at least 180 grit ( 220 is better)
Start with a "soak coat" first
Use a small rag to wipe on liberal amounts of oil and keep the surface wet for 10-15 minutes. Wipe off excess and let dry for as long as you want. but not less than 24 hours. this coat is very important as it seals the wood and the deeper the oil goes the better your protection against moisture later. pay attention to end grains as they soak up more oil.

2. Starting with 400 grit sandpaper. dip the sandpaper in a small amount of oil and sand in circular motions in a small area. the oil will begin to make a paste from the sanding dust, that you will want to push into the grain as much as possible. once the oil/dust paste starts to get stiff-ish, wipe off excess paste going across the wood grain. let dry another 24 hours. woods like ash ( or other wide grain woods) may require a sanding block to keep the wood surfaces flat. Clsoe grains like mahogany and Maples usually don't need a block.

3. Repeat step 2 useing 600 grit.

4. Repeat with 1200 grit

5. Take a 400 count cotton sheet and cut into a 12" square. roll into a very tight, smooth surfaced, ball.
use the ball as you did the sandpapers.. dip into the oil and "polish" the wood surface.
when the oil gets warm and stiff-ish,
wipe off VERY vigoursly WITH the grain, with a clean 400 count sheet ( balled up) damped with a VERY small amount of orange or lemon oil.
Buff and polish during and after this wipe off step and you should have a very nice glossy French polished finish. be careful of fingerprints.. as the oil drys, it will keep imprints in its surface.
I recommend you wear one cotton glove on one hand to hold the guitar with while you buff. watch for hard items on your worksurface. I fact I recommend that you use something soft to do this whole process on.

let dry another 24 and your done.

I prefer General Finishes Seal-a-cell and when I go to the 1200 grit paper i switch to Amour Seal also made by G.F.


This type of finish is not for the nambie pambie.. It require tons of elbow grease. Do it wrong and it looks like crap. do it right and it looks like a million bucks. if your arm is not hurting halfway through step 2... your doing it wrong.

Good luck.

[LouieAtienza]

I can't say I'm a fan of using Tru Oil for a top. Since it penetrates deep into the wood there is a good possibility that it can have a damping effect.

I have restored pool cues using tung oil, buffed to a high gloss.

I should add tgat Tobias has a pretty good finish schedul, but realize he builds solid body electric basses, where this finish is more prevalent.

[redir]

I've never tried True Oil but have always wanted to give it a shot. What about a shellac sealer so it won't penetrate so deep?

[GreenWoodworker]

Ive wondered the same thing since it soaks in, but i guess its doesnt really mean it will affect the sound. Ive heard it was one of the best finishes for the sound, not sure its true?

[LouieAtienza]

Plus it's not reversible. You can't unsoak the wood, and you'd have to sand a significant amount off if you wanted to remove it, which would radically affect the structure and sound of the guitar.

[WaddyT]

Originally Posted by LouieAtienza

I can't say I'm a fan of using Tru Oil for a top. Since it penetrates deep into the wood there is a good possibility that it can have a damping effect.

I have restored pool cues using tung oil, buffed to a high gloss.

I should add tgat Tobias has a pretty good finish schedul, but realize he builds solid body electric basses, where this finish is more prevalent.

Tru-Oil does not soak into the top any more than any other sealer or finish. This is another one of those myths out there. Scrapes right off, removing almost no wood at all. Shellac soaks in much more. Tru-Oil is also applied in very thin coats, not brushed, laying on thick leveling coats like most varnishes. Another way to seal the top against any soaking is to seal first with egg white, which is a wonderful, grain raiser, sealer, and sizing agent. Wipe or brush on egg white (no need to make a glair), let dry and sand 220 or higher to level the grain and remove unevenness.

[redir]

Hey Waddy how is it applied then? With a pad like FP?

+1 on the egg whites that's a regular staple in my finishing work now.

[Rodger Knox]

The key to a good TruOil finish, just like most, is good surface prep.
The difference is you can and should go much further in the surface prep, up to at least 400 grit, I use 800 grit for tops and other non-porous woods, instead of stopping at 220 grit. TruOil does not have the adhesion problems that lacquer does on surfaces smoother than 220.
Twelve coats is a minimum, usually 20 or 30 are required.
I've got a finishing schedule somewhere, I'll see if I can find it.

edit: I've assembled this from several prior posts on OLF
I seal the pores with shellac, and then sand back to bare wood.The pores don't have to be completely filled, but a couple of coats of shellac will seal them so that it only takes half as many coats of TruOil to fill the pores, and the initial coats dry faster. Be sure to sand back to bare wood, any shellac on the surface will show in the final finish. You can also leave a coat of shellac over the entire surface if you prefer the way that looks. TruOil has close to the same refractive index as wood, so you can see "into" the wood. Shellac leaves a slightly veiled look under TruOil. You can and should go much smoother in your prep work with TruOil, at least 400 grit and maybe as high as 1000, depending on the wood. Some finishes have adhesion issues on that smooth a surface, but TruOil works fine and sometimes that additional smoothness brings out more of the figure.

I warm the oil before applying by holding the bottle under hot running water for a few minutes so that the oil is warm to the touch, I'm guessing 110°F. On your forefinger place a drop of oil about the size of the white prosperous on a wooden kitchen match. Lay your finger on the guitar and make tiny circles as you expand the circle let your finger return to the spot you started as that will be where the largest amount of that drop will stay. You will tell by the feel when you need to get another drop of oil on your finger. Before reloading take your finger pad and rub everything you've applied in the direction of the grain. Just takes a moment. While your doing this turn the instrument as you investigate the surface. You're looking for uglies. I have a magnifier glass on my work station that has a bright light. I use this light to bounce the rays off the finish showing me any imperfections. Reload and continue to make those tiny circles. You're actually pressing the oil down into the pores of the wood. Continue making these tiny circles until the instrument is completely covered. There should be no runs sags etc, if you've wiped it all down good with your finger. Remember the thinner the coat the nicer the finish. Takes awhile in the beginning but as you get more and more coats. It takes less time to apply and almost no time to dry.

Don't try to build up enough thickness to go through the grits after it's cured, go through the grits with your sanding between coats. This is dry sanding only, if you wet sand TruOil, you're asking for witness lines.

Every on 3 or 4 coats, let it dry 24 hours and sand out all the shiny spots, working your way through the grits from 600 to 1000. That is, 3 or 4 coats and sand with 600, 3 or 4 more coats and sand with 800, etc. If you sand through it's no problem, you're putting on more coats anyway.
Warm the oil for the final few coats, and get it on really thin and smooth. Let it cure for a month and you're done.

[Ben-Had]

Originally Posted by Rodger Knox

The key to a good TruOil finish, just like most, is good surface prep. The difference is you can and should go much further in the surface prep, up to at least 400 grit, I use 800 grit for tops and other non-porous woods, instead of stopping at 220 grit.

You beat me to it Roger, this is the key and I go to 1000 grit.

[Gtar4Him]

New guy here - built one kit and working on my next. I used Tru-Oil. I didn't go through many of the above processes (they are probably better and I will revisit this post for my next. Just expressing my experience here). I did at first try to use it like a poly (watching some of the videos it gave me that impression). It actually went well until the 3rd or 4th coat, then the finish started streaking. I sanded it down to bare wood finishing at 400 grit. Then applied with micor-micro dots and applied about 5 coats. My impression was you apply just a tiny-tiny bit, spread it over the surface and then try to wipe it all off. Folks say to "remove the excess" but that doesn't really describe what you are doing. You literally are trying to wipe it off. What remains is a micro-film. Let it dry and reapply. I did not sand between application.

I went through a 3oz bottle the first time out - NOT RIGHT! A friend told me that a 3 oz bottle should last for about 3-4 guitars... maybe more. So micro-film means micro. At 5 coats I got to where I liked it well enough and left well enough alone. I used quality shop towels in small pads for application, then a little larger pads that I would fold and re-fold for clean removal with the grain. I'd throw away each set after application, starting with fresh.

[Rodger Knox]

That's a great thing about TruOil, even doing it "wrong" usually gets pretty decent results. You used way too much oil, put on too thick, and not nearly enough coats. You followed the directions on the bottle.

Don't misunderstand, the technique you used is quite correct to get the results you got, it's just not the best technique for what most people consider a good guitar finish.

[LouieAtienza]

Originally Posted by WaddyT

Tru-Oil does not soak into the top any more than any other sealer or finish. This is another one of those myths out there. Scrapes right off, removing almost no wood at all. Shellac soaks in much more. Tru-Oil is also applied in very thin coats, not brushed, laying on thick leveling coats like most varnishes. Another way to seal the top against any soaking is to seal first with egg white, which is a wonderful, grain raiser, sealer, and sizing agent. Wipe or brush on egg white (no need to make a glair), let dry and sand 220 or higher to level the grain and remove unevenness.

I agree that applying it in the fashion described will result in less absorption, especially when used with a sealer. That's pretty obvious. But this can be said of most drying oils, even thinned varnish and even shellac and lacquer and urethane.