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| Builders and Repair Discussions for those with an interest in the construction and repair of mandolin family instruments. |
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#1 |
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Registered User
Join Date: May 2007
Location: Philadelphia
Posts: 53
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I have a 20's Gibson instrument that will soon be going through a restoration. I would not normally refinish an instrument but this one came to me stripped of all it's original finish so it necessary to apply a new one. The people who I have do my repair work, and who I trust, said that the best finish for it would be a varnish finish. The only problem they mentioned is that it might be difficult to get the actual varnish to use as there are laws prohibiting the shipping of such products. Any advice that either I could do or that I could pass on to them as to what can be done?
Thanks, Phil |
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#2 |
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formerly digger b
Join Date: Dec 2006
Location: n/c illinois
Posts: 45
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check in your area for an exotic woods or hardwoods dealer. They may have the correct finish in stock. Not all finishes are created equal.
Sounds like a great project. |
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#3 |
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Registered User
Join Date: Feb 2008
Posts: 246
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As an organic solvent, you will have to do a hazmat shipment to do it by mail. Fed Ex will ship hazmat for an extra charge, but it must be signed for by an actual person, not just left.
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#4 |
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Registered User
Join Date: Oct 2003
Location: Turlock, California
Posts: 1,087
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Have whoever is doing the restoration just make their own shellac based varnish, maybe with a little sandarac. It's easy. I refinished an F2 (once owned by Curly Seckler)with that formula and also a Larsen parlor guitar. The end result was very good. Check out my blog. Also, most Gibson products probably had a spirit based finish any way. At least the cheaper products. It's drying properties just makes sense for a large factory output. Lacquer wasn't around until the mid 20's, right? And oil finished just take too long to cure for factory output. None of the ingredients to a fine varnish require any shipping license or HAZMAT fee. Making finish,ESPECIALLY spirit based finishes is the best idea. Spirit(alcohol) continues to break down the ingredients and at some point the varnish loses it's drying properties. Fresh is always best.
OK here you go 1 part bleached or blond (or any color you want) shellac flakes 1/10 part sandarac 1/10 part mastic solve this in denatured alcohol.....filter it........and start application! Any luthier supplier has mastic and sandarac, and Home Depot carries denatured alcohol.
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vesselmandolins.blogspot.com |
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#5 |
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Registered User
Join Date: Mar 2006
Location: Sylva, NC
Posts: 976
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20's gibsons typically had a oil based violin style varnish base (nobody knows the exact formulation, I don't think) with a thin spirit varnish (shellac) French Polished top coat. Check with international violin or any of the luthiery supply shops, they should have both.
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#6 |
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Formerly F5JOURNL
Join Date: Feb 2003
Location: aiken, sc
Posts: 4,816
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I agree with Testore. I've done several '20's A models and it works well and blends with the original finish. I am convinced the A-models were nothing more than that until they changed to a soft lacquer in late 24 early 25. I have had good luck airbrushing it and you can do mixed in color coats underneath if you wish also
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#7 |
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Registered User
Join Date: Oct 2003
Location: Turlock, California
Posts: 1,087
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I've never seen a quality oil varnish that would dry quickly enough to make factory production possible. And when you look at the pre Loar stuff, the way it wears, it is absolutely a spirit finish. The exact formula isn't that important either. None of the spirit varnish recipes are very complex and the end results are fairly similar.
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vesselmandolins.blogspot.com |
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#8 |
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Registered User
Join Date: Sep 2002
Location: Grass Valley California
Posts: 2,579
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I have a '25 F4 in for some work, it has spirit varnish all over, and too thick I think. It has checked significantly along the grain lines from excessive moisture. I think a thinner application would be a better choice if applying new finish.
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http://www.michaellewisinstruments.com |
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#9 |
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Registered User
Join Date: May 2006
Location: Santa Cruz, CA
Posts: 1,352
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Loar's ViviTones look to be done in spirit varnish as well...and those are from the early 1930s.
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#10 | |
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Adrian Minarovic
Join Date: Oct 2003
Location: Banska Bystrica, Slovakia, Europe
Posts: 569
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Quote:
I believe they used this kind of finishing (at least) on higher models. The brushing marks, sags runs and finish on edges of trussrod pockets look like oil varnish. Shellac based spirit varnish will blend nicely with almost every finish so it's also good for restoration.
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Adrian |
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#11 |
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Registered User
Join Date: Oct 2005
Location: Kalamazoo, Michigan
Posts: 462
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What Adrian said. Old-fashioned q-d phenolic w/FP over. All the evidence is there, says I.
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~Bill~ |
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#12 |
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Capt. E
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The best way to apply a shellac based spirit varnish is in multiple THIN hand rubbed layers. A mandolin is identical to any fine furniture. One of the great things about a shellac finish is ease of removal and repair. It is also transparent and beautifully reveals the wood grain. It went out of favor in furniture primarily because it is sensitive to moisture. Ever seen those white rings left by the condensation from a glass? That's why coasters were invented. Not much of a problem with mandolins.
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Jammin' in South Austin with: '70's Shiro A '08 Weber Bighorn LeCapitaine Accordion Harmonica Penny Whistle My albums: http://www.mandolincafe.com/forum/album.php?u=7616 |
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#13 |
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Registered User
Join Date: Oct 2003
Location: Turlock, California
Posts: 1,087
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I'm mostly talking about the teens A's, low end F's and non Loar products of the 20's. I still find it hard to believe that they would spend days finishing an A model in 1918. With a spar finish,a few coats and 12 hours of drying time, then French polish? I don't believe it. With spirit finish the whole thing can be done in a few hours, ready for a rub down the next day. They had that figured out in Mirecourt France by 1870 in the school/factories there. Spar finish and French polish on a Loar...sure I have no problem with that. There certainly is a ton of difference in appearance between an F2 from 1918 and a Loar.
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vesselmandolins.blogspot.com |
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#14 |
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Adrian Minarovic
Join Date: Oct 2003
Location: Banska Bystrica, Slovakia, Europe
Posts: 569
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I'm not sure about lower end A's but F-4s of early 20's (and perhaps F-2s) were done this way, too, not only Loars.
They used aniline stains and spirit varnish would smear them more easily. Could be that they treated sunbursted instruments differently than simple brown or blonde.
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Adrian |
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#15 |
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Hester Mandolins
Join Date: Feb 2004
Location: Poulsbo, WA (Seattle)
Posts: 1,598
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Somewhere there is an old thread that showed a teens/20s Gibson factory picture of a Benjamin Moore can of oil varnish. It seems to me that if the finish was ever just spirit varnish it could be removed with the 95% alcohol I use for FP. I have not found that to be the case.
I don't claim to know what was in the earlier Gibson finishes although I believe it was oil varnish during the Loar era. I have read that hemp oil was common in furniture finishes of that period and it is a fast drying oil.
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Gail Hester Last edited by Gail Hester; 04-16-2009 at 02:02 PM. |
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#16 |
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Registered User
Join Date: Oct 2003
Location: Turlock, California
Posts: 1,087
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I've never stripped one, but oil varnishes strip with denatured too. Depending on formula.
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vesselmandolins.blogspot.com |
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#17 |
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Café habitué
Join Date: Sep 2003
Location: Santa Cruz, California
Posts: 4,160
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I agree with Gail - that old Gibson varnish is damned hard to strip or bite into with even acetone, much less alcohol or lacquer thinner. It's extremely susceptible to heat. It flexes, obviously, and the spirit varnish that Gary proposes, with sandarac, would mimic it, and would of course adhere and build, but I wonder if it's as tough as the old Gibson varnishes.
We know they did not spend days applying those finishes. We know they were applied with a pad, by hand. I sure wish we knew more than that. Like: what was the actual formula.
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. ph º º º º º º º º º º º º º º º Paul Hostetter, luthier Santa Cruz, California www.lutherie.net |
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#18 |
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Hester Mandolins
Join Date: Feb 2004
Location: Poulsbo, WA (Seattle)
Posts: 1,598
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Hey Gary, interesting discussion and I’m all ears as I would like to know what the finish is as well. I guess my point was, if the old finishes were alcohol based as in all of the constituents dissolve in alcohol, wouldn’t it soften or even come off with 95% grain alcohol? I have never been able to strip an old Gibson or get anything but the shine to react to alcohol.
Note: Posted at the same time as Paul.
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Gail Hester |
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#19 |
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Registered User
Join Date: Oct 2003
Location: Turlock, California
Posts: 1,087
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Gail,that's good to know. I've never stripped any Gibson finish off, so I'm glad to know it's that durable. Sounds like an oil base doesn't it? It must not have any turpene based ingredients(like cooked rosins, or similar ingredients) because that stuff flies off with alcohol. Strad varnish still does too. Hmmmmmm, Don't know. The f2's I've seen don't impress me much, but whatever they had was thin at least on the backs. Could have been a simple hand rubbed situation. BTW, I've been told that the violin factories in France had a spray system in place in the late 19th century for varnish application.????I don't know if it's true or not. When did compressed air come about? This is a fun topic, In the end it really doesn't matter very much does it. There are a TON of good finishes out there. Maybe even some better than Gibsons was.
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vesselmandolins.blogspot.com |
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#20 | |
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Adrian Minarovic
Join Date: Oct 2003
Location: Banska Bystrica, Slovakia, Europe
Posts: 569
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Quote:
"I've never stripped one, but oil varnishes strip with denatured too. Depending on formula." I have yet to see an oil varnish (based on drying oil like linseed) that dissolves in denatured. SOme violinmakers call "Oil varnish" also varnishes made from evaporating oils used to dissolve resins like simple oil of turpentine/damar gum varnish and similar. The comparison with Mirecourt is not good, they were making ten times more instruments than Gibson at any time and back then ingredients of spirit varnish were much cheaper that in 20's when synthetic resins for oil varnishes became quite cheap and worked very well. Application of spirit varnish and subsequent abrasive polishing would remove brush marks and runs which most Gibsons show even after 80+ years of use.
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Adrian |
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#21 |
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Café habitué
Join Date: Sep 2003
Location: Santa Cruz, California
Posts: 4,160
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Yoohoo:
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. ph º º º º º º º º º º º º º º º Paul Hostetter, luthier Santa Cruz, California www.lutherie.net |
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#22 |
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Registered User
Join Date: Oct 2005
Location: Kalamazoo, Michigan
Posts: 462
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Thanks, Paul.
Sorry folks, it's not a 'teens/20s Gibson factory photo -- that's a can of varnish that was very old when I obtained it from Al Lakey, I guess in the '60s or '70s, when I asked him if he knew what Gibson put on their mandolins before 1925. Al ran a paint and art store in Kalamazoo and knew a bit about the old days at Gibson, and the people who worked there. Of course he did not mean that can was from the '20s, but was merely indicating the type of stuff they used. I'm not sure how to do a successful search and I don't have time to re-write it now, but somewhere in the foggy past I posted my take on the whole thing based upon my restorative experiences and observations on layers, drips & sags, solvencies, wear & crackleur patterns, and so on. Probably still out there somewhere. Certainly not the last word, just history and food for thought.
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~Bill~ |
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#23 |
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Hester Mandolins
Join Date: Feb 2004
Location: Poulsbo, WA (Seattle)
Posts: 1,598
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Thanks Bill, I'm sure that's what I was referring to. I sure can spin a yarn in my head.
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Gail Hester |
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#24 |
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Registered User
Join Date: Aug 2008
Posts: 32
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If we are talking varnish composition, if im not mistaken, pure shellac over time becomes incredibly solvent resistant, and its the added soft resins like Sandarac or Gum Mastic that make it softer and work in a similar way to the plasticizers found in lacquer. A varnish with mastic will adhere well to itself and the wood. Benzoin will give a wonderful shine but is considered very soft. There are lots of resins that could have been used. But one important ingredient added in the old days was a hard resin called Copal. Its like fossilized tree sap and takes forever to dissolve. But im not sure if they used it at Gibson.
Best, Tony |
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#25 |
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Registered User
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I remember that can!
As for the "vintage" spraying concept, find an OLD art store and see if they have a grunbacher "Spray atomizer" they have been in production forever. Not saying this would be practical for applying a whole finish but, artists will use them for applying varnish to paintings. Must take a lot of lung power!
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Timothy F. Lewis |
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