MIMF

I thought I'd try Tru-Oil for a finish on a spruce & walnut steel string acoustic, no grain fill, no fussing with it, just 3-4 coats done. Any experience with how Tru-Oil might interact with perspiration on a hot three hour gig.

French polish is a complete bust in this regard, one warm gig can destroy a shellac finish. Two years ago, I switched over to sprayed marine varnish, polished out and I'm very pleased with the look and durability, and if some one wants a high gloss finish, this does nicely, but it is 1) a slow process and 2) as my guitars mimic vintage instruments, I think at least some people would prefer a less glossy finish.

I tried out some Tru-Oil on test panels and I like the look and feel. I tried a small puddle of water on the panels for an hour and they do water mark. The gloss is dulled and there is a minor shift in color. The panel sealed first with shellac was most affected, the all Tru-Oil panel the least. Recoating with Tru-Oil restored the gloss, but did not fully restore the color. The all Tru-Oil panel was the best.

I left a small puddle of 190 proof alcohol on each of the panels for about 15 minutes, much longer and stronger than if I spilled my scotch on a guitar. The panels which I had used nothing but Tru-Oil resisted the alcohol completely. On one panel, I sealed with shellac first and this panel marked with the alcohol, but a fresh wipe of Tru-Oil restored it completely.

Perspiration, however, is another matter. Any tales from the trenches?

BTW, the panel which I sealed with the Tru-Oil Sealer/Filler looked no better than the all Tru-Oil panel and water marked noticeably more than the all Tru-Oil. I don't see much use for the sealer.

CB

I have nothing to contribute, as I've not yet used Tru-Oil: however, I wanted to remark how surprised I am at your shellac+Tru-Oil vs. straight Tru-Oil results. Many folks throw down a wash coat of shellac under many finishes, but your results show that might not be the best idea. Does this mean that the Tru-Oil is permeable enough at 3-4 coats to allow liquids (presumably sweat) to penetrate and cause changes to deeper layers? Would the color shift you saw in the shellac sealed test piece be seen in shellac alone?

I had a bass customer who had very corrosive sweat. He was able to strip a true-oil finish off in less than a week. I shot the bass with nitro and he stripped that off in a matter of months. Not all sweat is created equal so I would simply wait and see what happens. Escalate as needed or simply have a pro finish the instrument in polyester and be done with it.

Don't know how you applied the Tru-Oil, but 4 coats is not much when wiped on. Even on Sycamore, with no pores, I put at least 7 or 8 coats. The finish is still very thin. Rubbed back after each coat with a gray pad. The guitar has not been played a ton, but it has been to a few shows, and has been played at those, with no visible issues. I doubt anyone has really sweated on it for any length of time though.

Maybe cure time is an issue here? Again, I've not used the stuff, but plan to.

Although some finishes are tougher than others, it seems like most will eventually wear off a heavily played guitar neck. The beauty of tru oil is it can be reapplied after a light steel wooling (to clear the crud) to restore the finish.

Jason, yes, I think with my samples at least the shellac offered no improvement in the appearance and seemed more susceptible to both water and alcohol damage.

Waddy, okay, I'll try more coats and see what happens. If I have to apply dozens of coats though, I might as well stick with my varnish system.

David, corrosive sweat is the problem I've run into as well. How many coats do you use? Very hard on shellac finishes even when applied over varnish sealer. I've heard perspiration can be hard on nitro as well. So far, my marine varnish system holds up which is to expected as it is designed to withstand ocean salt water, hot climates and direct sunlight, a very potent combination. I like it, but it is 3 weeks start to finish and high gloss. A two day finish with low gloss would be a nice trick to have in the bag.

Not to shift the thread, but I was very happy with the results of a sample of Grafted Coatings "Ten" water based urethane finish. I was only able to get enough to finish one guitar last year, but I thought it was great stuff. Apply a coat every 30 minutes until you get a solid base, sand out to dead flat the next morning, shoot three more coats, wet sand and buff with Menzerna the same afternoon. Done! Tough, durable, water clear, decent hand feel. They say they are still working on development and testing. Sigh...... By contrast, I did not like their K-9 water based acrylic much. Nice enough looking but had kind of a sticky, draggy hand feel that was unpleasent and gets worse with perspiration, especially not good on necks.

If I remember correctly, in an AL article with English builder Gary Southwell, he reported using a dozen or so coats of Tru-Oil on the back and sides, and seven or so on the top. I was going to go with this on the handful of instruments I need to finish.

If you don't need the gloss but want additional harness and great water resistance I still recommend the OSMO poly-x. It's my go too fast finish, especially nice on necks because it's in the wood not on the wood. Hardly any smell and seems to always dry hard in 8 hours. It's not inexpensive but I can probably finish 5 instruments with the one tiny can.

Dave, Thanks for the suggestion, I ordered a small bottle of OSMO Polyx-0il, .125 liter to try. I read the application guide for furniture. Do you scrub the finish in with a white abrasive pad as they suggest? How many coats do you use? The application guide says three for the most durability. The application guide suggests easy touch up and repair, have you found this to be the case?

If 3-4 coats are enough, you're putting it on too thick . I use at least a dozen, sometimes as many as 30.
I've posted my TruOil schedule a couple of times, it may be in the library.

Craig Bumgarner wrote:Dave, Thanks for the suggestion, I ordered a small bottle of OSMO Polyx-0il, .125 liter to try. I read the application guide for furniture. Do you scrub the finish in with a white abrasive pad as they suggest? How many coats do you use? The application guide says three for the most durability. The application guide suggests easy touch up and repair, have you found this to be the case?

Craig, It's an oil so whatever works best for you to wipe up the excess without marring the wood surface. I use a cotton wipe designed for cleaning printing press rollers. It's very absorbent and won't scratch. On a softer wood I'd go easy with the scotchbrite non-abrasive pads. They work well but they could burnish an open grain wood a little past what was intended.

What's hard for people to understand is that this is not a surface coating like tru-oil or varnish. You need to wipe up every trace of it soon after application after it's had a chance to soak in but before it dries. Re-coating later couldn't be easier but you may want to lightly sand the surface to remove any embedded grime from the grain on a neck that's seen a lot of use. It's a floor finish and once the natural oils have had a chance to polymerize it's very hard and water resistant.

David, yes, it is a bit hard to believe an oil that is not a surface coating can impart sufficient hardness, and water resistance, but I trust your suggestion sufficiently to order some (done) and give it a try on some samples. Being a floor coating has to count for something. The Germans don't usually make junk. I'm hopeful it will work for me.

Thanks for the suggestion!

With regard to perspiration, and I also finger marks, you may well want to consider trying Renaissance Wax as a final finish over the top of whatever you use, tru oil, shellac, whatever. Renaissance Wax is recommended as a preservative finish for museum quality exhibits, including very fine furniture, marble and other items of great value. http://www.picreator.co.uk/articles/3_r ... ce_wax.htm and also http://en.wikipedia.org/wiki/Renaissance_Wax Applied over the top of most finishes it should not show fingerprints and can be used on fingerboards, raw wood and all sorts. It is now the only finish I use on tonewood. I can vouch for the fact that the surface can be cleaned with a damp cloth. It isn't shiny or gloss, so if you want that look apply something else first. It is specifically mentioned to prevent fingerprints forming. My thanks to Master Luthier Ben Crowe at Crimson Guitars for putting me onto this substance.

Incidentally I have tried Osmo oil. It rewuires a rub down qith fine grit paper between the first an second coat. A white sheen was apparent after the fourth coat. I haven't used it on an instrument yet.

Wow, 4-1/2 years later I’m searching the interwebs for information on OSMO Polyx and Renaissance Wax and I find my way back here. Long live the MIMF!

I've used truoil on a few guitars and I agree with the guys that say more coats. I think its a very thin finish.
re: waxing the guitar. Really? Seems to me wax is a sure way to dampen the sound.

Wax does not dampen the sound. It's too thin to do much of anything except put in a tiny layer of protection. It makes a nice final finish that is a softer sheen than polished look. Also, when it dulls off, which it will in wear areas, you can hand buff it right back up. It's also quite easy to touch up with a tiny bit of wax. I use Briwax, but Johnson's or any other type of good floor wax should be fine.

Hey Waddy thanks for clearing that up for me. I do love the look of buffed wax.