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What do you guy's think is really the best finish for a classical? I have made three classicals so far, two finished with lacquer and one with USL. I'm wondering if for my next one I should learn to french polish. I don't want to waste my time learning if it is not really needed. Would there be a noticeably better sound with one that is french polished rather than one finished with KTM-9?

Colby,
I'd bet you will never know the difference between FP and KTM-9 as far as the sound goes, but in theory, FP should sound better because it goes on thinner. Also, if you are going to be selling your classicals, then FP is the way to go. For some reason, FP is associated with classical guitars. I think you will have a better chance at selling them if you use FP.
Tracy

I have a guy who I have made a couple of instruments for and he is a semi pro musician, this guy has a great ear, he can hear if inotation is a couple of cents off !

He always maintains it is not the lacquer or any other finish that makes the difference, but the grain fill, he won't have grain filler used on any of his guitars, on the two I did for him I french polished the soundboard and oild finished the bodies.

I can't hear the difference myself but he maintains it is there, and on the grounds he is ten times the player I will ever be, I take his word for it.

Colby,

what do you want the finish to do or not do for that matter? Some things to consider are protection provided, durability, easy of application, safety, appearance, reparability, etc.
According to renowned luthier Richard Brune “ Your choice of a varnish should be based on a musical decision, not a decision of convenience nor even necessarily of appearance. A harder thinner finish will give you a louder, brighter quality of sound. A softer more flexible finish will give a quieter, duller more muted quality of sound.”
Based on the quote from Brune, French Polish is an excellent choice but may not meet other expectations you may have.
good luck.

Hi Robbie

Alot of stuff I have read says about wax being a real no no for instruments, but have often though it would be nice to use paste wax over oil, what is your take on the wax ?

Many thanks

Any finish I put on my instruments that will be rubbed out to a satin I apply and then "remove" a coat of fine quality paste wax. My take on wax is "why not?" It sure makes the finish look nice.

Thanks Robbie

Al Carruth and I had a discussion last Sunday on finishing and french polish. (When you go to a luthier's meeting, it seems that all anyone ever talks about is finish) At any rate, he said that over a long period of time wax will start to disolve the shellac and turn it into a mess. He said that this was noticable on tables and cabinets because no one ever waxed the side and legs which would be fine while the top was all sticky.

There is the possibility that I'm misremembering what Al said or misunderstood so it would be better to ask Al.

[QUOTE=RussellR]
He always maintains it is not the lacquer or any other finish that makes the difference, but the grain fill, he won't have grain filler used on any of his guitars, on the two I did for him I french polished the soundboard and oild finished the bodies.
[/QUOTE]

Russell,

I have heard this very thing from a few different sources. I've been playing classical guitar for 33 years, and I'm still much more a guitarist than I am a luthier, so I too am sensitive to this issue. In fact, I have used this very viewpoint as an excuse not to fill pores in my guitars up until my current build.

With the current one, I'm using pumice as part of a french polish finish. Honestly, I'm finding -- on this guitar at least -- that pumice is just kinda so-so as a pore filler. Most of it seems to get removed when I go back over the surface to remove the dried residue. Probably just my technique though.

I've french polished all my guitars, which, except for one, have all been classicals. I prefer the thin hard finish that shellac provides. But it is so much work trying to get the instrument to look halfway decent that I keep threatening to switch over to KTM-9. My fear is that the KTM product will not have the hardness or clarity that shellac provides.

Best,

Michael

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Live to Play, Play to Live

Michael

On the french polishing, I have made contact with a local furniture maker and I am going for some lessons in a couple of weeks, his technique for getting a fast and good quality finish as he describes it to me is to spray with a shellac based sanding sealer then spray, a couple of coats of shellac, and hand polish out from there. I will know more once I have been for my lessons.

Russell

Mike remembered what I said correctly. Whether it's _gospel_ or not is another matter. I remember reading something to that effec6t years ago: that you need to remove old wax once in a while or it will melt into the finish and turn it into goo. I've sure seen enough goo on table tops to make that plausible.

Oil does not form a protective film. It also penetrates deeply into the wood, adding a lot or weight as you build it up. Finally, oils have very high damping: they tend to 'eat' high frequencies in particular. For all of these reasons oil is probably not a great finish for a classical guitar, and particularly not on the soundboard. There are more gorey detaisl on this in a study published by Schleske in the Journal of the Catgut Acoustical Society several years ago, in which he compared a bunch of different finishes.

FP takes a while to do, does not protect against mechanical damage as well as many other finishes, is effected by too many solvents, and it less transparent than you might like. I still love it on a classical guitar. You really should learn to do it, even if you don't use it most of the time. It's as much 'standard practice' in the classical world as nitro is for steel strings.

This looks like a good spot to ask a question I've been pondering - Can you put a more durable finish over your French Polished work?

I got some cheap tops to practice fp and quickly learned to do some kind of pre-finish because when you do start filling you can get unpleasant streaks of color.

It seems to me that if you can put sanding sealer under FP, there should be a protective finish you can put OVER it. FP for depth without thickness and a modern urethane or epoxy to protect the surface from blood, sweat & tears. Feel free to chuckle but I think like that! 8^)

I can't really see why you couldn't as you can use Shellac as a seal coat under most things, but I'm not sure you would get the effect you are after, but I guess you would have to try it to see if you like the effect.

Mike Doolin claims that epoxy won't adhere to shellac. Just passing it along.

I have a can of Minwax gloss wipe-on poly (as in polyurethane), but I haven't tried it on guitars yet. Might work fine, but I personally don't like putting urethane on acoustic instruments. Maybe if it can be applied in thin enough coats, it'll work ok.

Best,

Michael

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Live to Play, Play to Live

Shellac is very durable, Unless you plan on dumping 180 proff Rum on it why put anything over top?

The problem with FP is often not so much the 'softness' of shellac as it is the thinness of the coating. That's the point, of course; less finish has less of a detrimental effect on the tone, but it offers less protection, too. You could always take the time to build it up more, particularly on the back, sides and neck.

It's amusing, really: a hundred years ago shellac was about the hardest finish around, and Gibson ads used to rail about the 'glassy hardness' of it (on thier competitors instruments). Now nitro, which is about 1/3 harder than shellac, is considered 'soft'.

I think one outcome of this move to ever harder finishes has been a sort of desensitization. People _expect_ their guitars to take the sort of abuse that, say, their car, or a Formica ccountertop, can. I'm always having to caution people to be careful of the tops on my French polished instruments, and often they simply don't seem to believe it, and scratch them up anyway. I've resigned myself to a month or so of polishing after every major show. :(

Shellac does react with alkaline water solutions, and for a lot of folks, that's sweat. There's no getting around this, except by the passage of time. Shellac continues to react long after it's 'dry', and after about 75 years it's insoluble in anything: stripper won't touch it.

Jimson:
What sort of shellac were you using that was giving you streaks? Some of them do have a lot of color, but if you get them even enough they won't make straks. I use seedlac, a pretty highly colored material, from start to finish on spruc tops with no problems. Maybe it's a surface prep issue? French polish is really all about surface prep.

Martin used to use a regular oil varnish over shellac. For that matter, it's entirely possible that Strad did, too. The main thing to watch for after adhesion problems is the old painters rule of 'fat over lean'. Always be sure that you don't put a hard finish over a soft one. The layer underneath will try to move and the stuff on top won't be able to move with it. Instant 'antique'.

Now, a lot of folks do use lacquer over shellac, and seem to have no problems. Perhaps they are using such a thin layer of shellac that it doesn't move enough to be an issue. I have seen lacquer over shellac check badly in a relatively short time.

At any rate, most varnishes are more flexible than shellac, so they'd be OK. But that leaves you with something softer that is hard to touch up as 'protection' over your easily repaired shellac surface. Hmm. Sort of like a gig bag?

I believe that if FP finish isn't tough enough for a player that it's likely to get scuffed and scratched, then they just don't have the respect for the instrument that it deserves. People like that should only be allowed to own Ovations! I can be so cruel.

Colin

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

Colin,
You are such a hoot!

[QUOTE=Colin S] I believe that if FP finish isn't tough enough for a player that it's likely to get scuffed and scratched, then they just don't have the respect for the instrument that it deserves. People like that should only be allowed to own Ovations! I can be so cruel.

Colin[/QUOTE]
Cruel? No you seem to be one of the lucky few who can be careful and have it work. Me, I'm a klutz. I respect and love my guitars and desperately try to keep them safe. All of this is to no avail. It always seem to be little unexpected things that get me. For example, one of the latches stayed in the upright position on a case once. When I went to put the guitar away, scratch. Once I was playing while sitting on the bed, I took my capo off and lightly tossed it on the bed about a foot away from the guitar. The capo bounced off the bed, straight back at me and hit the guitar giving me a nice little dent.

Usually, I have no idea how the dings and scratches end up on the guitar. I notice them well after they happen. The only thing that seem to work at keeping my guitars unblemished is to put it in the case and stare at it from across the room.

I'm with Colin on this one. Classical players who are buying high end guitars want a FP 99% of the time, and they seem to understand how to treat a delicately thin finish.

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Yeah, and remember, FP is one of the easiest finishes to touch up. Most little dings, and even some big ones, can be made to dissappear. Thank goodness.

And not to mention... its inexpensive, a rewarding process, and doesn't require a respirator.

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Web: https://www.jfrenchguitars.com/

Hmmm . . . Well, I haven't reached that "rewarding" stage yet, although I remain hopeful. :) Gotta agree about the ease of touch up and the lack of harmful fumes, though.

Best,

Michael

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Live to Play, Play to Live

[QUOTE=jfrench] And not to mention... its inexpensive, a rewarding process, and doesn't require a respirator.[/QUOTE]

As usual I have to totally agree with Joshua, I find french polishing to be one of the most therapeutic tasks you can do, something to do with the repetitive movements of the application. And rewarding, just go and look at the guitars on Joshua's site to see how rewarding it can be. No wonder they named the process after him!

And of course Alan's right, (when isn't he!) get a scratch, get the shellac out, ten minutes later no scratch.

Colin

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

Thanks guys, you've given me a lot to think about.