New Luthier Tips du Jour video - Tru Oil

[Nick]

I just used tung oil as a sealer on an electric and am planning to seal the tung oil with shellac (a bit of an extra step but oh well). Next time will just use shellac and try out this tru oil stuff. Cheers Robbie

You're sealing a sealing coat?
This is purely speculating but I would say make sure the Tung oil is well and truly dry & hard before trying to put anything over the top of it. I've never done it (& could be well & truly wrong ) but would say the Tung oil is too 'oiley' & fairly heavy for another finish to go over the top of it & stick, but let us know how it goes Stu.

[needsmorecowbel]

I was going off a suggestion if it works it works...all part of the experimentation process

[brian64]

I've bought Tru-Oil at a gunshop on Clayton road in Clayton (Vic), but found then found it much cheaper on e-bay. If you buy a few bottles, (which will last better than a big bottle), it works out much cheaper than buying it in Oz. It is about $5.40 (A$) a bottle so it isn't difficult to beat the $13-$14 a bottle from the shop even with shipping once you get a few bottles. I can post the vendor I got it from if anyone's interested.

Here is my latest finished with Tru-oil. It's hard to capture the gloss on the photos.


Cheers,

Brian.

www.briandyskinguitars.com

[needsmorecowbel]

you probably are right nick as i have had very little experience with finishes

[pavliku]

Can I get a good result using true oil over timber I have pore filled with shellac and pumice ?
Thanks, Paul.

[Robbie O'Brien]

Thanks Robbie, your video makes me think I should try it at least!

What about shelf life? I couldn't locate any seller of Tru Oil in my country so I'll have to import it which makes small quantities very unattractive.

someone posted this link above.

http://westernfirearms.com.au/cleaning- ... -2699.html

Markus is a Swiss member Robbie, so from anywhere is an import

Yep, you are right.
With all those guns in Switzerland there ought to be someone who knows how to get tru oil there.

[charangohabsburg]

Hi Robbie,
In Switzerland all wooden guns are in the museum now.
Even the Swiss Army Knife has a plastic handle!

[needsmorecowbel]

Nick I am only using a thin layer of shellac above some 100% tung oil. Then I'd apply the truoil above the shellac if all goes well. Apparently according to my sources (paint shop, Woodworks in Sydney and now a boating forum you can ) if you let the tung oil cure for 2-3 weeks between coats then you complete the chemical reaction and it no longer gasses off. Then you are free to seal it with a more hard wearing coat i.e. hard shellac or shellac then tru-oil. You are probably scratching your head as to why i have done it this way. But so am I. haha

http://forum.woodenboat.com/showthread. ... p-tung-oil

[Nick]

Nick I am only using a thin layer of shellac above some 100% tung oil. Then I'd apply the truoil above the shellac if all goes well. Apparently according to my sources (paint shop, Woodworks in Sydney and now a boating forum you can ) if you let the tung oil cure for 2-3 weeks between coats then you complete the chemical reaction and it no longer gasses off. Then you are free to seal it with a more hard wearing coat i.e. hard shellac or shellac then tru-oil. You are probably scratching your head as to why i have done it this way. But so am I. haha

http://forum.woodenboat.com/showthread. ... p-tung-oil

No as you say, it's good to experiment & we will never know these things unless we do! (you could say alot of my early spraying attempts were under the guise of 'experimenting' ), I just wasn't sure how it would go & seems my guess of letting it fully dry/harden was close to the mark Be interested to see how it turns out Stu.

[Dave Higham]

What about shelf life? I couldn't locate any seller of Tru Oil in my country so I'll have to import it which makes small quantities very unattractive.

Although the question has been asked, nobody has given a clear answer. Once the bottle has been opened Tru Oil starts to thicken up and harden (in fact it oxidizes). It's not a problem for one instrument, but if the next time you want to use it is a year later it will probably be useless. Even so, it skins over in the bottle very quickly so it's best to store the bottle upside-down between coats. Rick Turner advised using Bloxygen (an inert gas in an aerosol) to extend its shelf-life once opened but I've never found this, or an equivalent, in Europe. So that's why it's best to buy small bottles.

I once bought some from David Dyke in the UK. He'd obviously bought it in bulk and decanted it into smaller bottles. When I opened it a few weeks later it was virtually useless. I finished up getting it from the UK and postage wasn't bad.

I got it here:
http://cgi.ebay.co.uk/BIRCHWOOD-CASEY-T ... 45fb670845

but there are a lot of sellers on Ebay UK now, and this one looks cheaper:
http://cgi.ebay.co.uk/Birchwood-Casey-T ... 53dcc55307

By the way, everyone calls it an oil finish but it's really a varnish.

[charangohabsburg]

Thank you Dave for reading (and answering) my question. Indeed, it was this kind of answer I was looking for . So it must be the small bottles to go for.

You are providing some great info here. It's also good to know that one should not even open the bottle just to "see how it is" or how it smells if not intending to use it within the next few days.

[...] Rick Turner advised using Bloxygen (an inert gas in an aerosol) to extend its shelf-life once opened but I've never found this, or an equivalent, in Europe. [...]

There is an equivalent I use for wine when I don't get to the bottom of a bottle:
http://www.winepreserve.com/

Thank you also for the ebay links. Both of these vendors sell cheaper and at a better shipping rate than this one I had in mind.

Cheers,

[Nick]

There is an equivalent I use for wine when I don't get to the bottom of a bottle:

You're a worry Markus.

[charangohabsburg]

There is an equivalent I use for wine when I don't get to the bottom of a bottle:

You're a worry Markus.

Yes I know, I'm not a great beer drinker.

[Kim]

What about shelf life? I couldn't locate any seller of Tru Oil in my country so I'll have to import it which makes small quantities very unattractive.

Although the question has been asked, nobody has given a clear answer. Once the bottle has been opened Tru Oil starts to thicken up and harden (in fact it oxidizes). It's not a problem for one instrument, but if the next time you want to use it is a year later it will probably be useless. Even so, it skins over in the bottle very quickly so it's best to store the bottle upside-down between coats. Rick Turner advised using Bloxygen (an inert gas in an aerosol) to extend its shelf-life once opened but I've never found this, or an equivalent, in Europe. So that's why it's best to buy small bottles.

I bought a large bottle a few years back, used it on one guitar and its still fine. The trick is to buy a bag of marbles and each time you use the product, drop enough marbles in the bottle to bring the liquid up into the neck so it expels most all of the air before you re-cap.

Cheers

Kim

[pavliku]

Hi everyone,

I have been using true oil to finish a guitar - I decided to use the product after reading this thread so I will post my question here.
I had put on about 8 coats - It looked ok so I decided to go ahead and postion the bridge. While doing this I was taking some tape off the top and noted the finish had dented under pressure from my fingernails - I experimented a little and discovered under light pressure only found the surface particularly easy do dent on all parts of the guitar but most pronounced on the top.
Is this normal? Can I expect this to change by applying more coats? if so how many coats should I apply for a good hard finish? - or is the product less durable than I expected?
I think it's just a question of how much build of finish I have achieved, but I'm not sure, so I guess it's better to ask those who have experience.
Thanks in advance.
Paul

[brian64]

Hi Paul,

Hardness has to do with how long you leave the product to dry between coats as well as how many coats. I have found that older Tru-Oil actually takes longer to harden too. In any case it will never be as hard as poly or nitro, if that's what you were expecting.

Is the top a softwood (I don't know if you're building acoustic or solidbody)?

How long has it been since you put the Tru-Oil on? What sort of finish did you get (matte, satin, gloss?)

Brian

[pavliku]

Hi Brian thanks for you response.

The tru-oil I used was from a brand new bottle. I put on two to three coats a day in the spare room which was kept reasonably warm (18- 20 c) and the RH was about 40%. I have since left it to sit in that enviroment for about a week. I went for a matt finish rubbing it back with 0000 steel wool.

I am building a classical guitar - WRC top, IRW back and sides and Matai/ Jarrah composite neck.

Can I expect the finish to harden more? should I give it some more coats? I was expecting a hard finish - If it isn't posible to achieve a hard finish with this product would I be able to put another product over the true oil, eg poly, pre-cat lacquer etc ? I can't really be bothered stripping the whole thing back to bare wood.

Can I ask how many coats you have used on your guitars?

Thanks, Paul.

[brian64]

Paul, it sounds like you've done everything right. I usually use more coats than that, especially on the top. I don't consider myself an expert, but I have used more coats-around 20. I have only finished one softwood top with tru-oil and it is still going well after 4 years.

There is a bit of a compromise with tops-the harder the finishing material, often the more it negatively affects the sound. More coats, more protection, less vibration. I understand that French polish gives the best protection to sound ratio, but i've been too busy/lazy to learn it. Poly is probably one of the best for protection but worst for sound.

JMHO

Brian

[pavliku]

Thanks once again Brian.

I'll add some more coats and see how things go.

Paul.