French Polish vs Nitro Finish

[mercy]

what is called violin varnish is actually shellac so maybe thats part of the confusion along with their being French and not fully acculturated in English.

[Wade Hampton]

Originally Posted by mercy

what is called violin varnish is actually shellac so maybe thats part of the confusion along with their being French and not fully acculturated in English.

Yeah, I don’t want to give any credit to those French guys, so I call the finish on those three instruments “Freedom polish”....


whm

[Rosewood99]

Originally Posted by Wade Hampton

Yeah, I don’t want to give any credit to those French guys, so I call the finish on those three instruments “Freedom polish”....


whm

Je ne comprends pas?

[musicman1951]

The Eastman site calls the finish antique varnish, so I'm not sure where the French polish came in. I don't think you should be at all unhappy, you might be better off with varnish.

French polish is a bit of a fussy, labor intensive finish. I'd be surprised to see it on a guitar in this price range.

[Pura Vida]

It came from their website, describing the process:

https://www.eastmanguitars.com/antiq...e_varnish_hero

"A six step process starting with a basecoat application to fill the grain, moving to color application, concluding with a french polish, resulting in a finish that’s softer than lacquer, with a smoother tone."

[Pura Vida]

Originally Posted by Alan Carruth

The question is, assuming guitars do change over time, what's changing? Is most of the change in the finish/glue, as some think, or is it the wood? IMO it's the wood, so the type of finish used is going to be less of an issue than how much was used.

Most makers feel that finish is a necessary evil. You need to have it to protect the wood from moisture, dirt, and grease, all of which will harm the wood over time. The finish does add mass, though, and although it can add stiffness, particularly across the grain on the top, that may or may not be what you want. Of course, a really nice finish can also bring up the look of a pretty piece of wood, and we all appreciate that, but once you've got 'enough' to protect the wood and make it look nice, any more is a drag. The big advantage of FP is that it goes on thinner than any other finish that offers similar protection against moisture, dirt, and grease. It is also very easy to touch up or renew, once you know how.

That's an important point. The fact is that a couple of thousandths of an inch of any sort of finish is not really much protection. FP is not as hard as some other finishes, particularly the modern synthetics, so it wears faster. It's also less resistant to common chemicals than many other finishes: shellac is soluble in both alcohol and alkaline water solutions, which, for some folks, equals sweat. Don't be surprised if you start seeing wood through the finish in some spots on the neck or the edges. In the old days it was not uncommon for repairmen to touch up the polish on a guitar as matter of course every time it came in for some sort of adjustment. One nice thing about it is that shellac does become less soluble with age. The problem is that it takes about 75 years for it to really become impervious.

The bottom line, IMO is that most of the 'open' sound of a new FP finish has to do with the thin coating the doesn't impede the tone much. Since I feel that most of the change in tone comes from changes in the wood over time, I would not expect the finish to have much of an effect in that respect.

When making comparisons, of course, you're going to be looking at some finishes that really do hurt the sound, and can take quite some time to become less of an issue, if ever. Some of the water based finishes I tried years ago were, almost literally, a heavy wet blanket. They went on thick, and stayed relatively soft for a long time, and really 'ate' sound. Nitro goes on thicker than FP, but can be held to a fairly thin coat with care. Since it breaks down chemically fairly fast (as such things go) the tone may well develop noticeably due to finish change. UV cure polyester, which a lot of the manufacturers and some small shops use, is very hard, and should be quite stable over time, so I would not expect that to contribute much to a change in timbre. Some of the Ovations I worked on years ago, back when I did that sort of thing, had as much as .040" of epoxy on the soundboard for a finish. You're never going to wear off an appreciable amount of that, so the mass is always there, but eventually it starts to crack and that might free things up a bit.

Alan, I was hoping you might chime in. This is really helpful and gets to the core of my question (bold and italic added for emphasis).

Thank you!

[gitarro]

French polish in that price range is indeed a welxome development!

[Mr. Jelly]

I own a Waterloo WL-S and a Waterloo WL-S Deluxe. They are made the same with the same woods. One has a thin nitro finish and the other a varnish finish. The varnish has a slightly smoother sound.

[redir]

My guess is that it's not actually French Polished as that is a very labor intensive endeavour but rather it's sprayed on and buffed out shellac. Still a perfectly good way to finish an instrument but it's probably thicker then an FP finish. Finishing arguments are sort of like glue arguments. From my experience for example I cannot tell a difference between hide glue or Titebond but I absolutely definitely notice that FP has a positive impact on tone.

[zhunter]

In my experience this is a confusing subject. I tend to go with the narrow definition of French polish which is a technique that uses lac flakes dissolved in alcohol and applied with a pad. Often with a grain filling base/ground layer that incorporates very fine pumice on the pad along with the shellac.

I *think* some, maybe most, of the confusion stems from terminology. Lac in alcohol is sometimes referred to as spirit varnish. Similarly lac flakes can be dissolved in oil creating oil varnish. The two produce different results on the final product. And varnish can be other things too. It can contain modern ingredients to affect cure times etc and may not contain any lac at all.

To further add to the confusion, lac alcohol (spirit varnish) French polish can be applied over other varnishes to produce a nicer surface while the even softer oil varnish cures. Which means the finish is technically French polished but will behave differently from a ground up shellac French polish. And some may call any finish applied with a pad French polish.

After all that I still have no real idea what is in many of the "French polished" or varnish finishes offered by various makers. No doubt there are, by my definition, true French polish finishes out there but I suspect the term is used rather liberally and can mean a lot of different finish types to folks.

Hoping an expert can step in and help me understand further.

hunter

[k_russell]

Originally Posted by Wade Hampton

The missal wrote:



You’re a poet! I didn’t know New Jersey had any poets!!


Wade Hampton “Not From Jersey” Miller

Of course New Jersey has poets.......Joyce Kilmer even has a rest stop named after him on the NJ Turnpike.


I have 2 classical guitars with French polish finish. I have been playing one for about 10 years, the other for 8 years. I like the response, the look and the tone quality and the sound seems to be pretty consistent over time.

I don't own a steel string guitar with French polish. Those that I have heard sound better to me than those with nitro, but finish is only one of many variables.

[Pura Vida]

Hunter, thanks for your insight. Lots of good info here.

To the others, I appreciate your input, as well. Alan hit upon my question, which is how a guitar may react over time to a thinner finish, irrespective of what we want to call it. Based on what I've read and photos I've seen online, it definite appears to be a hand-applied finish, not sprayed on, as some have assumed. Most of Eastman's processes are still done by hand, which is something that sets them apart from other builders.

I'm loving the vibe on this guitar. It's super responsive, has great tone, volume, and sustain... and I am sure I'll continue to enjoy it as it evolves over time.

[Monsoon1]

Originally Posted by Wade Hampton

The missal wrote:



You’re a poet! I didn’t know New Jersey had any poets!!


Wade Hampton “Not From Jersey” Miller

I think Springsteen is from Jersey...

[Alan Carruth]

I've never heard of dissolving lac flakes in oil: so far as I know lac resin is soluble in alcohol and in alkaline water solutions, but not in plain oil.

Traditional oil-resin varnish is made by cooking a drying oil, such as linseed, with a resin at a high enough temperature to form a co-polymer. The resulting thick goo is 'cut' with a 'vehicle', such as turpentine or mineral spirits, to achieve a brushing consistency, and painted on the surface. The vehicle evaporates, and the varnish hardens by oxidation and polymerization. The hardened film is not soluble in the original vehicle/solvent to any great extent once it has fully cured, since it is no longer the same stuff. This type of varnish thus has much of the film forming ability and stability of the resin, the flexibility and toughness of the oil, and can be quite resistant to chemicals. Some oil-resin varnishes an be, or become, alcohol soluble in time.

The full-blown 'French polish' finish is traditionally applied with a pad from start to finish. That may, in part, simply be due to the fact that they didn't have spray guns in the Olde Days. In some respects the real 'heart' of the technique is not so much in the application as in the actual polishing stage, which is akin to 'spit shine' on shoes. That is, once the requisite amount of shellac (or other alcohol soluble resin) has been applied to the surface, a small amount of oil is introduced to the pad. The oil keeps the pad from sticking to the soft shellac as it is worked out smooth with pressure from the pad. Over time the amount of alcohol on the pad is reduced, the shellac on the surface hardens, and the pad picks up all of the oil, which, if left on the surface, would prevent the shellac from hardening. It's possible that Godin had dispensed with the tedious process of building up finish with a pad in favor of spraying or brushing it. They may then use sandpaper to level it out, and finally a quick 'spit shine' to polish the surface, instead of buffing mechanically as you would with lacquer. Shellac melts at a low enough temperature that it's fussy to buff mechanically, but can be polished up rather quickly with oil and alcohol, once the surface is level.

[Pura Vida]

Alan, based on their website description, do you have any thoughts on how Eastman is doing for their Antique Varnish series? They're usually very responsive, so I may send them an email, as well.

https://www.eastmanguitars.com/antiq...e_varnish_hero