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I just got off the phone with Birchwood Casey, talking with a guy about the composition, use, and purpose of their filler/sealer. I've been wondering what is accomplished by using it as opposed to applying the Tru-Oil to the bare wood. I had read their PDF brochure on finishing gun stocks and it makes no mention of using the sealer.    

The guy told me it's made with alkyd resin, proprietary oil, and a yucky soup of solvents - toluene, xylene, etc. The Tru-Oil, he said, doesn't have these nasty ingredients in it, the only solvent being mineral spirits. (Though we didn't actually discuss this, it's my understanding that the main ingredient of Tru-Oil is polymerized linseed oil.)

He said the sealer/filler will reduce the penetration of the oil into the wood. That seems to be pretty much what it does (I don't see why they call it a sealer/filler, rather than just a sealer), which any sealer would do. I would consider that an advantage on the body of the guitar (though I'd be more inclined to just use shellac for that), but on the neck I don't see the penetration of the oil as a bad thing.

The guy gave me his personal opinion, which was to skip the sealer and put the Tru-Oil on the bare wood. He said it's easier to apply that way and, in his opinion, achieves a better-looking end result.

So, I'm here to ask those of you who've used Tru-Oil, esp on necks, what your experience has been. If you've found an advantage to starting with the sealer, what is it?

Thanks! Todd Rose38741.632650463

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Hi Todd,

I use Tru-oil exclusively on my necks and perversely enough I think it gives a better finish if you apply it over a couple of coats of the Birchwood Casey Sealler/Filler. I find that putting a couple of coats of the sealler on first and then rubbing back all over with 0000 wire wool gives a better grounding for applying the Tru-oil as I do thinly using folded pieces of kitchen towel.

I agree it's definitely not a filler, and is pretty nasty compared with the Tru-oil itself (the warnings on the bottle hint as much), and you definitely have to use new stuff, the Sealer filler seems to go off in the bottle pretty quickly and "gums up" when you try to wipe on older stuff.

I've actually used the Sealer/Filler as a finish on Braz Rosewood back and sides on my baritone and like the simple look it gives. It wears pretty well too - it's been on there for 2 years plus.

Tru-oil on it's own on the neck will probably work just fine too.

One thing that I do is to polish up the neck wood all the way up to 10,000 grade micromesh so that the bare wood looks and feels as if it has a finish on already. the Tru-oil then goes on a treat.

Don't be put off that the neck feels a litle "sticky" at firts. Just keep playing and playing. After a week or so it settles down into a great feel and playabiliy. As Colin S. pointed out to me, what is happening is that you are buffing up the finish with your hand - apparently as his father used to do with gun stocks treated with Tru-oil.

I'd be interested to hear how you get on with a Tru-oil neck. Everyone who has played one of my guitars comments on the great feel and playability of the necks.Dave White38741.6521643519

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Hi Todd,

I used Tru-oil on my 1st acoustic (way back in 2004 ) & I really enjoyed using that finish.

On the Grenadillo back & sides and the mahogany neck, I first filled the pores with the Z-poxey resin (not glue) that many others here have used & liked. I liked it too - just thin it well with alcohol, & use a couple of thin coats. After scuff sanding the Z-poxey, the Tru-oil was wiped on over the wood in thin coats - twice a day on average.

No other filler/sealer was used & I actually had purchased the Birchwood Casey sealer/filler but in testing, I didn't like it - it didn't do anything that the regular Tru-Oil plus the Z-poxey filler hadn't already done.

On the Englemann top, I used two brushed-on coats of 2-lb waxless shellac as sealer before beginning wiping-on process with the Tru-Oil. This kept the Tru-Oil from seeping deeply into the spruce - a good thing!

Be aware that wiped on varnish is 1/3 as thick as a typical brushed-on coat. It takes three times the number of coats to get the same build! You'll wipe on 9-12 coats for a good finish build - more if you aggressively level sand.

Additionally, if you do use the Tru-Oil for your guitar, try level sanding lightly with 400 - 600 grit every 4th coat or so. Then after the last thorough level sanding, for the last two coats, thin the Tru-Oil with turpentine 50-50 & wipe it on carefully. Don't sand it again. Let it cure (2-3 weeks) & polish with medium, fine & super fine polish (I used Novus 1 2 & 3).

It really looks great & hold up well - very shiney but not too thick & plasticky looking. I love the feel of a Tru-oil finished neck - silky smooth without ever being "draggy" like a nitro finished neck can be when the humidity is high.

Good Luck! My apologies for repeating this finishing process for the 3rd time to those old timer OLF'ers who might have read it all before.

Skip

May a new builder, but long term TO and clone user pose an alternative? Try "sanding in" your TO. Cut 50% with min. spirits,make a bunch of folds of #320 and wet sand with the diluted oil finish. A slurry is created. Let it sit until it goes dull and then using cheap paper napkins wipe it across grain-gently. Repeat six to eight times(try to separate the apps. by 6-8 hours). All of your pores should be filled with wood dust bound by the finish. Cut 25% with min. spirits and repeat 4-5 times with 400 or even better 600 grit. Wipe more gently with these apps.Only 4 hours rest between apps. With your fingers smooth on undiluted TO-4 hours between coats. Do this about 4 times. The last two, really rub up the app even to the point that you feel friction heat. Let it sit around in a nice dry atmosphere for 2-3 days. Rub out with rottenstone and Behlen"s wool lube on a med.density piece of felt. The result will be smooth and at the same time will have a certain friction level needed for "thumb purchase." The finish will be tough but easy to restore or fill if dented. This tedious sounding method has been the fine hand rubbed oil finish that is the hallmark of the finest gun stock makers. It can be brought up to a gloss like nitro or anything in between(very high gloss with vigorous use of Behlen's Deluxing Compound) If you stop and think about it, this a form of French Oil Polish.

Mike,

Thanks for describing this technique. It's one I haven't heard before. I'll have to give it a try.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Here is another method from a builder with just a mando, dulcimer, and a few guitars under his belt:

Sand neck to 600 grit.
Wipe on Tru-Oil with as light a coat as possible. I use a paper napkin and make sure to wipe off everything I can.

Repeat 3-4 more times.

Play. After a week or so it will feel nice and smooth.

I've also used it as a pore filler under nitro. Use it as a lubricant to wet sand with 320 grit. I really like the way it looks on walnut.

Thanks Dave, Skip, Mike, and Bruce for all your helpful input. On the guitar neck I'm working on right now, I think I'll just start wiping thin coats of Tru-Oil onto the bare mahogany, making no attempt to fill the pores. With the wood sanded/polished up to 12,000 grit micromesh, it already feels ultra-smooth, and I don't plan to buff it to a high gloss, so I think the open pores will be fine.

Thanks again for sharing your experience and ideas.     

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Mike,
This sounds pretty similar to what Robbie O'Brien has used in the past. He uses a very light (1 lb.) cut of blonde shellac with end grain (very fine) saw dust as a pore filler. It seems to work very well. I plan on using something similar to this on my next neck.
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy