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For awhile now I have been researching some different options for finishing guitars in my small shop. Spraying any type of finish is pretty much out of the question due to limited space and off-gassing in living areas.

I have been googling and am finding a lot of infomation based around the finishing of violin family instruments in oil based varnishes. I have also found guitar varnish available and am guessing it is a bit harder, but it is from the Tulsa Luthiers who seem to have had a busy signal for the last few years.

In addition to clear finishes I am interested in doing hand rubbed 'bursts as well as black finishes.

After digging into the OLF archives I have yet to find anything that answers these questions. If you are using or have used any type of oil varnishes (other than Tru Oil, my prefered method for necks) what have you tried? Successes and failures encouraged and welcomed please.

stewmac do a waterbased guitar lacquer.

I've put it on with a sponge and after a few coats it buffs up nicely with steel wool for a semi satin finish.

I USUALLY spray it, but I sponged it "just to see", y'know?

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My soundclick xx luthier blog xx luthier soundclick

What's wrong with Tru-Oil as a final finish all over? It's hard, it's thin, it's acoustically transparent, it's easier than French Polish of Shellac, and it's used by others as a final finish.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

My question is what wrong with French polish? Many formulations use that can add other resins to the cut besides shellac. In my opinion it is the ideal hand rubbed guitar finish and there are two pre cut mixes on the market. both made by Zinzzer. Seal Coat or French polish. I prefer Seal Coat. They both will require either pure grain alcohol or DA to use as the carrier solvent but the smell is not harsh. There is a reason it is among the longest used finishing techniques

I would agree with you, Michael! I just got the impression he was looking for something less labor intensive, and Tru-Oil is, somewhat, easier.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Martin, thanks for the tip on the lacquer.

WaddyT, I have been using the TruOil for neck and like everything thing about it for this purpose. I remember reading a post (which I now cannot find) in the archives that said (paraphrasing) that TruOil wasn't desired for softwood tops, though I cannot remember why (do you remember this thread?).

MichaelP, to me FP seems like the best way to finish a new guitar. I am interested in learning this technique, but am a bit reluctant as it is alcohol based. A lot of players I know are not shy about their bourbon consumption and the oil varnish seems to be a better match for habits like these.

Have you all had any luck with Behlen's RockHard?

The problem in my opinion on Behlen's Rockhard is the damping affect but can work well. I have often use it on necks.

French polish is not really that much more susceptible to alcohol damage than is your typical Spirit varnish. Alcohol will damage almost any varnish

Tru-oil is a fine finish for the whole guitar, one $15000 classical builder that I know, uses it as his only finish as it is the acoustically best finish in his view. Many top concert players use his guitars. If your worried about penetratio on the top, then just use a seal coat or two of shellac, problem solved.

My usual finish on my guitars, like Michael, is French polish. I use the pre-mixed Liberon de-waxed blonde shellac. If properly applied (the milburn tutorial is as good a guide as any) then it can give a thin very hard, but easily repairable finish.

That said I have just finished a guitar in a restoration hand rubbed oil varnish, as this was the finish on the original model and it has been very successful. I'll be posting the guitar in a day or two, so you'll be able to see what oil finished can look like.

So, in summary, look no further than either French polish or Tru=oil.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Andrew, I've been using Behlen Rockhard for over 15 guitars now. It is a beautiful finish. It is happy applied with a good brush or sprayed. It buffs beautifully but is slightly more fragile than lacquer at first. It continues to harden with time. It doesn't yellow or check like lacquer. There is a learning curve but it is not difficult, much easier than doing a "real" FP for example. Expect around 20 hours to finish a guitar if you're good, including scuffing between coats, wet-sanding and buffing.
I have never been satisfied with shellac, FP or not, it looks gorgeous at first but degrades pretty quickly. At least if the guitar is being handled and played, like it should, and especially if the player has an acidic sweat. The easy repairability is a myth, try re-FP a guitar around the bridge, neck heel and FB if the neck was originally finished separately from the body and you'll know what I mean. The "new" shellac added to the "old" shellac always shows, at least under serious scrutiny. Besides who would want to re-touch a guitar finish every year or so?
I use shellac, and now Behlen violin varnish (as recommended by Bruce Sexauer), as a sealer before the pore-grain filler and the 1st varnish coat. Behlen violin varnish is a spirit varnish (shellac with added resins), as opposed to an oil varnish (cooked tung or linseed oil with added resins). I may try Waterlox as a sealer before the Rockhard for my next instrument, I need to do some tests.
Stay away from the violin varnishes, oil or spirit based, they're too soft for the way a guitar is handled.
Tru-Oil dents easily and will never buff to a high shine. Feels great on the back of the neck though.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Andrew,

The violin and guitar varnishes that ILS sells are both oil-based spar varnishes. They are relatively flexible and protective, but probably not the best finish out there. I have a 30 year old guitar that has ILS varnish, and it has held up pretty well, but it was never very glossy. More of a satin finish. It also has a hard time drying when its brushed onto rosewood.

Behlen's rockhard, Tru-oil, or french polish would be your best bet.

Do you want a pore filled look or open pores?

For pore filled, many of us are using epoxy under any number of top coat finishes. Works great and cuts way down on the number of coats of anything you put over it.

Thanks to all for the information on your experiences with the different types of varnishes.

Laurent I really liked the couple of guitars you have recently posted. I had forgotten that they were finished with (Behlen's rockhard) varnish. For your guitar that had a sunburst did you hand rub this, or spray?

Rick, I do like the look of both (filled and not). For a few recent banjo necks of some fiddleback mahogany I filled one and not the other with Zpoxy; I couldn't decide which one I liked better. For these flattop guitars I am definitely planning on filling the pores. I just need to remember to stop by the auto parts store for a 6" and hopefully a 14-16" squeegee (sp?) before I start to fill.

Again thanks for sharing your experiences. Soon I hope to post a few images of some new boxes.

The sunburst was sprayed nitro with clear coats of brushed varnish. BTW there is absolutely no damping with Rockhard. Personally I do not hear any differences between lacquer, varnish, shellac or urethanes, provided they're well applied, and applied relatively thin (between .004" and .008"). It is, in my mind, another myth. Over .010" of finish and perhaps each has different tonal characteristics, I do not know…

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Laurent, if you are using a spit coat of shellac and then varnish before pore filling, what are you using to pore fill? It is my understanding that epoxy doesn't adhere well to shellac.

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Joe Breault
Merrimack, NH
Perpetual novice

I vote for French Polish too. I've tried three different finishes and this is the technique for me.

Just to be sure this is understood!!! There is no problem with shellac over epoxy. There are issues with epoxy over shellac. It is a mater of the epoxy having the proper substrate to adhere to. Shellac will adhere do darn near anything .

Behlen Pore-O-Pac natural with various oil stains mixed in, and sometimes the black waterbase pore-filler sold by StewMac. Seems to work well so far.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

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Tony, what company used spirit varnishes for guitars at the turn of the century? Just curious.
From what I've seen Martin used pure shellac (probably sprayed I assume) before switching to nitro around 1930. A small 0-18K from 1928 I restored a couple of years ago still had all its shellac finish in great shape (it was hardly played).
Presumably Gibson instruments of the previous era used an oil varnish.
All spirit varnishes I've seen are a tad too soft for the guitar BTW. Because of the resins they also tend to take a while to harden and cure.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

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Behlen's instrument varnish is a pretty good spirit varnish. You can brush it or spray it. You could probably pad it if you thinned it enough.

Tony, at the risk of arguing… The pre-nitro Martin guitars I've seen exhibit no trace of resins or gums in the finish. Pure shellac it is. Maybe those were freaks? I don't know. There is no difference between refined and crude shellac. After adding alcohol strain it to get rid of the impurities, let the wax sit on the bottom of the can and keep the "pure" shellac. You can buy the crudiest shellac and refine it on you kitchen table. The clearer colours like blonde are obtained with bleaching at the factory level. As far as I know Martin used a blonde, refined shellac no different from what we can find today. Again that's based on a few guitars going through my shop, those maybe exceptions…

Requirements for violin and guitar finishes are completely different. I persist and say that all violin spirit and oil varnishes I've seen are too soft for the guitar, period. A "hard" varnish for a violin maker is still too soft for a guitar. Maybe one needs to look somewhere else though, I am not going to try all artisan, floor or furniture finishes out there, it's a waste of time.
I settled on Belhen Rockhard after many trials, failures and half-successes. It fills all I expect from a guitar finish for now and so far it's been exactly the same thing in the can, can after can.

I am not 100% sure but I could swear factories were already spraying finishes in the 20's and before.

Experimenting I did, do and will always do. May I ask where you get your information? Do you make your own spirit varnish? If so please share with us, seriously.



Rick, this is what I now use as a sealer before the Rockhard. It works great and is very transparent. It needs to be thinned around 50/50 to be sprayed, as it comes out of the bottle quite thick, almost like honey. It is too soft for a final finish on the guitar though, after 2 days of curing at 68º/45% humidity lightly pressing my nail still leaves a mark.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

As has been mentioned, there was a great link to FP finishing in the UMGF that digressed just nicely enough to cover other materials as well. I'd like to re-post a link that I put there to an amazing resource -- the Gutenberg Project. The information can be downloaded at the bottom of the first page as a zip file (or in other formats). There is a plethora of information and historical mixes here:

http://www.gutenberg.org/etext/17935

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Jim Howell
Charlotte, NC

I believe that Martin was using a spirit varnish for a couple of years before they switched to nitro in the late 1920s. I'm not sure when they went to spraying. DeVilbiss invented the "modern" spray gun in the 1880s, but it took a long time to catch on. Nitro lacquer got a big boost when Ford switched over to it for Model Ts which had been hand painted.

I am not sure general furniture or piano finishing really applies to guitars and violins, bit it sure is useful information. For those interested in violin finishes I highly recommend Edward Heron-Allen book written in 1885, Violin-Making: A Historical and Practical Guide, there's an extensive chapter on oil varnish (he laments the use of spirit varnishes on violins BTW) http://www.amazon.com/gp/product/0486443566/ref=wl_it_dp?ie=UTF8&coliid=IS2YNZ1387EJY&colid=3UO4AO9MPZM4T
The Hills books on Cremona makers (Stradivari, Guarneri) are also a must read, although poor on finishes.
Also this on terpene violin varnish:
http://www.scavm.com/Fulton.htm
And finally Otis Tomas on his varnish process:
http://www.cranfordpub.com/otis/reflections/on_varnish.htm
I am sure there is much more but that's all I can think about now.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/