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Do I need to apply a pore filler to the body of my newly assembled guitar prior to applying Tru-oil, or can a just begin with tru-oil right on the raw wood. And I saw where someone taped off where the bridge will be, so as not to get oil on that area. Is that necessary?

It is not necessary but it saves you the step of having to remove the finish where the bridge is going before gluing. Pore filling is a preference. Most people like to pore fill because it leaves a nice even finish. Others don't mind the pores. Some wood doesn't even have pores to fill. You can pore fill with Tru-oil if you like. Just use sand paper to make a slurry with the oil. It takes several coats depending on the wood and the size of the pores. I've done this before but I put a coat of shellac down first to prevent ebony from bleeding into maple.

Read the directions on the bottle. It helps


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Hi Julie, welcome to the forum.
You'll probably get as many suggestions as replies.
I've only done 2 guitars with Tru-oil.
I seem to remember the bottle suggests using their own filler, Birchwood Casey Gun Stock Sealer & Filler.
I tried it but didn't really like it, seems to leave a patchy haze under the Tru-oil if you don't sand back perfectly to the wood. That was one indian rosewood and one silkwood.
What woods are you using for B & S + binding?
Some don't need filling, and some people are happy to go with the open pore finish.
I recently pore filled with egg white (slurry with sandpaper) sealed with shellac, and then used an oil finish built up to gloss, worked out reasonably well, and was relatively easy and inexpensive, but open pore can look great too if it isn't overdone - easier too!

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Some woods (Indian Rosewood), you'll definitely want to seal before applying Tru-Oil. Otherwise it takes forever to dry. Something in the oils make it incompatible. If you seal it well the problem goes away.

Pore filling will save a lot of time on woods that need it. Otherwise it's lots more coats and sanding back after each one. Tru-Oil will fill them, just takes a long time.

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Waddy

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Waddy I agree EIR takes forever for the first coat to dry. About five days. Each coat dries quicker then the last. About the third coat overnite. Tenth coat. Two hrs max. Plus RH has impact. I'm making a EIR baritone Uke with eleven coats. A thin coat is dry by the time you finish it. I'm talking super thin coats of course. I thought the first coat would never dry. Been using the product since the sixties. I never use a pore filler the oil does a fine job. Just takes like forever to put on thirty coats. My next build is already started. Walnut much more open wood. I did shellac it as I'm going g will take all off except stopping short of the wood. Two reasons it toughens the wood during construction. Plus walnut has big gaping pores so I guess that my filler. Doing what I said not to Huh?


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Birchwood Casey, makes a good Sealer too. It dries really fast, and seals Rosewood quite well. Kind of expensive in those tiny little bottles though. Dries to sand in about an hour. Has more smell, due to the volatile base.

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Waddy

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Waddy I've never used it. I was in gunsmith school in Santa Rosa ca in the sixties. We were taught to just use the oil. I was thinking of doing a video of the proper application. Tiny drop on the tip of your pointing finger. Make little circles till it's all gone. Wipe the area with your finger with the grain. Birchwood Casey says steel wool between coats. That's exactly how we were taught in school. That's still written on the bottles. I know some folks use wet sand paper and make a slurry. Never having seen it done I don't know the benefits. They say it fills the pores. Pressing the oil into the pores with your finger fills them.
Finishing gunstocks is about the same as guitars more wood on a guitar of course. Walnut gunstocks have large pores. But like I say the more coats you have on the less time it takes to dry. Our goal on a gunstock is to take one drop of oil and stretch it over the entire stock. That happens about 19 coats into the process. Like I said I put a coat on my Uke and it was dry by the time I finished applying it. Lots of different ways. I heard some folks spray it on. To me that would be less time consuming then applying it by hand.


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Gosh, thank you all so much. I am learning that there are numerous methods. The guitar is mahogany b and s, and spruce top and my first. I am kind of leaning toward just going straight with the Truoil and applying many coats. Anther question is should I apply the first coat in a circular motion and the rest with the grain.

Julie: Just a few comments. If you do decide to use a filler, don't use epoxy base such as Zpoxy. It tends to end up with a rough surface over time. Regular filler will be fine. If you are just going to use Truoil by itself you may want to think about gluing your bridge on before finishing. That little tidbit should raise a bit of commotion. I have only done two guitars with oil finish and I glued the bridges first. My thought process was that if oil finish got on the bridge area before gluing it may cause a problem down the road, also with the rubbed oil finish it is relatively easy to work around the bridge. Good luck with the finishing and please post a few photos.
Tom

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Tom, thank you so much. And, gluing the bridge on first sounds like a very reasonable idea. I am looking forward to finishing it. Many thanks. julie

I generally apply Tru-oil with small pad made from a cut up sheet of those boxed paper towels from big box stores. I put the Tru-oil on the pad and squeeze it to spread the oil evenly in the rag, then lay on the finish with the grain in even strokes. Let it dry for 2 hours, sand back, repeat. Up to 3 - 4 coats a day that way. The closer to the end I get, the less oil I put in the rag, and the further I try to make it go. Last coats are very, very thin, and require very little leveling and polishing.

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Waddy

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I've been considering truoil instead of lacquer on a current electric build.
From what I have seen on the inner web, most folks raise the grain and sand up to 600 grit before applying the truoil.
Is this what you guys do?
Dan

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Wah-wah-wah-wah
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Waddy, thank for the technique explanation. What do about the bridge area?

I finish with the bridge on, but that's up to you. I try to limit the amount I apply at the bridge so I don't get too much build up.

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Waddy

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Julie no matter what method you decide on remember be very sparing with the product. Very thin coats is the secret. No runs no drip no errors. I've found when applying with cloth is I get way to much product on. Causing those problems I spoke of. Read and follow the directions on the bottle. They haven't changed in fifty years so it must be a good way.


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I thought I'd give you a little more help. When applying the product. Using a tiny finishing nail poke a little hole in the paper seal covering the bottle. 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. Your actually pressing the oil down into the pores of the wood. I've made a stand in which to hold the instrument while I apply the finish. I'll post a picture of it if I can. Basically you drill a hole in the instrument where the end peg goes and slip it onto a peg that is inletted into a heavy base. I use two 2x6's glued together about 18 or twenty inches long. It holds the instrument while I apply the finish. Continue making these tiny circles untill 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. Run steel wool over each coat before you apply the next coat. Good luck if you have any questions just ask.
Lonnie


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I would resist using an oil finish on the area of the bridge. Mask that area with frisket film and than apply the finish. Don't forget that oil finishes will penetrate the wood more than other finishes, and that can interfere with gluing the bridge, or rather getting the best possible glue joint.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

My first finish was unfilled mahogany back and sides with cedar top, I was really pleased with how the mahogany came out.

http://acousticguitarconstructionforum. ... =24&t=1657

Mike I checked out the photos. Very nice.


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I'll +1 everything Lonnie said, application method and all.
Two small differences in our methods, I seal the pores with shellac and heat the oil before application.
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.
As for heating, I hold the bottle under hot running water for a few minutes so that the oil is warm to the touch, I'm guessing 110°F. I also apply with the tip of my finger.

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thanks Lonnie.

Rodger on my newest build I am trying the shellac route. Old gunsmith Methods die slow I guess. But I'm willing to try new things.


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I'm not a gunsmith, but I did build a black powder pistol from a kit back in the 70s. I believe that's the first time I used TruOil.

As for the shellac, I use a really thin cut to raise the grain on the top, brushed on and sanded back with 400-600 grit once or twice.

To porefill the back and sides, I use a little thicker cut of shellac, but still pretty thin (about 2lb cut).
The shellac highlights the low spots, and I go through the grits from 320 to 600 and eliminate the shiny spots, just like I was polishing out a final finish. I brush on a coat or two of shellac for each grit, and let it dry overnight before sanding. That sometimes fills the pores, but usually they're still visible. They are sealed well enough to keep the oil from going too deep, the further the oil is from air, the longer it takes to dry. That's an exponential relationship, twice as deep take 4 times as long to dry. It takes me between a month and six weeks to get it done, and I don't polish out the final finish after it cures. That give a nice "soft" gloss that I prefer to the high gloss of polishing.

There are some woods that inhibit the oil from drying, such as pao ferro (aka Bolivian roasewood, morado) and it doesn't dry. I gave up after a week and cleaned the oil off. I put on a seal coat of shellac, and the oil dried normally.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Hmm!Sounds good. I love this forum ask a question get lots of answers. I did shellac the top on the last Uke I built. Scraping off to glue the bridge down now.


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