1927 Gibson A1 snake head - advice needed on color and refinishing

[Mike Keen]

Greetings from England.

 I've recently bought a 1927 blackface A1 (82390 in the Archive). It's very sound structurally, has a good voice and seems to be complete with all original fittings. Unfortunately the back has been badly oversprayed with black paint at some point and the front has been touched up. There are also several cosmetic blemishes. So it really does need to have some refinishing work done.

The untouched sides and back of the neck are dark brown and appear to be french polished, where as the untouched black peghead could be French polished or might have a top coat of nitrocellulose (haven't tested yet). I'm good at french polishing and so will probably refinish with french polish.

I wonder if the forum could give me some advice.

1. How can I make my french polish black to closely resemble the original colour - Indian ink???

2. How can I make some dark brown French polish to match the sides. It's very slightly lighter than 82103 on the Archive

3. Finally in the Archive some most of the backs of this model Gibson most LOOK black while some are dark brown. Should the back colour match the sides, or do some have brown sides and black back.

Thanks for your help.

Mike

[Dave Yelverton]

Mike..I think questions 1 and 2 are fairly easy to answer. French polish comes in several different natural colours. The lightes

[Dave Yelverton]

Don't know what happened with the first reply. Didn't seem to upload properly! Anyway....

Mike..I think questions 1 and 2 are fairly easy to answer. French polish comes in several different natural colours. The lightest is the transparent polish which is bleached shellac.Next is lemon shellac, then orange, then button and for a really rich dark brown you would use garnet polish. You can buy them already made; I suggest John Myland of London as very old established polishing supplier.

Of course if you want to make your own then you will need to buy shellac flakes and alcohol. Relics of Witney are a useful source: http://www.tryrelics.co.uk/catalogue/D/11
They supply ready made polish as well as flake shellac.
If you have read American articles about French polish, which insist on using 95% ethanol, forget it! Nanny State UK makes it practically impossible to obtain ethanol. However, if you look on Behlen's UK site you will find Behkohl which is a denatured product and may well be the nearest you can get!
Finney's also supply a superior uncoloured methanol for polishing. You can find them here: http://www.finneyswoodfinishes.co.uk/
Most suppliers will carry black polish (ebonising polish). I think it contains carbon (lamp black as in Indian ink) but I doubt if I could achieve as good a product mixing my own, so prefer to buy it ready made.

Achieving the exact shade you want might be tricky, so to give a little more flexibility, try either adjusting with spirit colours, or stain the underlying wood with water stain and cover with a light polish.
Hope that's some use.

Dave

[Mike Keen]

Thanks Dave

I didn't know it was possible to buy ebonising polish, will check it out tomorrow, and orf=der in some garnet shellac.

Best regards Mike

[Mike Keen]

I've now removed all the overspray and have got down to the original finish. The black face of the original finish is soluble in ethanol, the brown is also ethanol soluble but is much harder than the french polish on face or the french polish on my earlier A3.

I could still do with some more advice on matching the original dark brown colour on the back. I think the finish is called Sheraton brown.

Currently there are several places where the shellac has come off (the rest of the finish is sound). The wood is stained a light redish brown, but the finish on top also seems to contain opaque pigments. I've made up the Garnet French Polish as suggested but this is clear and is a lighter color.

Has anyone got experience of refinishing Old gibsons with this kind finish.

Cheers Mike

[Dave Yelverton]

If its opaque, sounds like pigments are being used. Liberon make a good range of earth pigments which I have made use of in odd touch-up jobs. Can't offer specific advice I'm afraid as I have never worked on this model, but perhaps Frank might have some pearls of wisdom to offer.

Dave

[Ned Knepp]

I own a black snake head too ( can't read the serial but I think it's a '24-'25 ) but I haven't worked on the finish. Looking at mine, it seem clear that the finish can't be just a dye in shellac. There is no sign the wood grain that I would expect to see with that technique though it's completely possible that they did this too. On my mandolin, there is a small area, right next to the tail piece, where the forearm rubs against the finish, that has worn through. Looking at that in the sunlight this morning, it appears that the wood was also stained. The color of the wood appears to be more of black/green. I can't say for sure that this is true but it appears that way on mine.

The back/sides are brown but, to my eyes, there is the slightest hint of red in it too. May this is Sheraton Brown. I've never actually seen the color defined anywhere. I've never seen a Gibson A with black back/side. I've seen higher end models with much more red back/sides but never black. BTW, the brown on my back/side set doesn't seem to be quite the same as the brown that was on the A junior that my brother had. That didn't seem to have the red component in it, at least on the top and I've heard this referred to as "Sheraton Brown" too. I can't remember for sure if the sides matched the top but it seems like they did.

Of course, this is Gibson so anything is possible.

Ned

[Mike Keen]

Dave and Ned thanks for your replies.

Yes Ned on mine you can't see the grain. The exposed section of wood (birch) is dyed pinkish brown. I've cleaned the original finish and it appears that over the stain there is another layer of very opaque browns dark pinky browns that have appear to have been vertically applied with a brush. On top of this is a very dark brown with a hint of pink. Not the most attractive gibson finish although the black face makes up for it.

I wonder if it's a form of nitrocellulose? Reading up on the net most nitrocelluloses are not soluble in ethanol. The finish is soluble in ethanol (and will french polish up), but is more resistant then the shellacs I've handled, and contains far more pigment.

Anyone else got any ideas?. I guess I could try patching the exposed section with acrylic paint topped with shellac.

[Mike Keen]

Just for information - I think I've worked out what finishing coating were used on this mando. This might be of interest as it's just when Gibson switched from French polish to Nitrocellulose. This mando is possibly an "experimental" batch.

The black top and front peghead is French polish and appears to have a thin coat of Nitrocellulose lacquer.

The back was first stained with a pinkish mahogany stain, it then had some kind of brown opaque stain applied vertically with a course brush (which hides the wood grain).

Except for the front and the peghead the mandolin was finished in a brown coloured or clear varnish (NOT French polish or Nitrocellulose), which is not touched by Ethanol or cellulose thinners (probably oil based).

[Paul Hostetter]

That mandolin would have had a nitro finish. Gibson never used simple French polish anyway, but rather a spirit (padded oil/shellac) varnish.

Gibsons ordinarily had dark brown sides and backs. Some were oversprayed at the factory in all black, usually those were refurbished seconds and returns.

India ink has no place in finishing.

My advice to you would be to turn this over to a pro who knows how to do good lacquer finishes. You'll save lots of time and money. The FP route is not a good one, especially if you want to doit balck again. You could FP over a black finish of some sort, but...why?.

[Mike Keen]

Hi Paul

Thanks for you reply

I was posting the information for people on this website. I know you're a professional luthier with many years experience, so please forgive me for questioning your reply. From what I've been able to find out this mandolin wouldn't have had a complete nitro finish as it's too early - in fact it's just at the point Gibson switched over to nitro, although for a few months they ran both processes. Also thanks for the advice, but I'm quite skilled at instrument renovation and don't feel I need to turn it over to a professional.

Also are you really sure about Gibson finishes? I've spoken at length to one of the key people involved in the Gibson Mandolin Archive. According to them, early Gibsons prior to the mid 1920s are French polished. This is confirmed by my 1921 A3 white face which has French polished back and sides (not sure what the white is). The finish readily dissolves in ethanol.

You refer to padded oil/varnish. I'm confused how is this different from the usual French polishing process?
I assume you're talking about the oil that's normally used in the French polishing process. A little bit of this may get incorporated into the finish, but this is part of the normal French polish process eryone now uses and surely not a technique in its own right. If it's a different technique can you provide me a link so I can read up about it.

According to the expert I've spoken to, he thought that the black face was usually French polish oversprayed with nitrocellulose. This appears to be the case with my black face and is how I'm restoring the finish. Is he mistaken - to your knowledge how were they finished?

Finally, it's well known that Gibson experimented with different finishes. Ned (earlier reply) seems to have a similar Blackface to me. It was obviously an experimental finish that they tried before deciding to use nitro as the standard finish.

So, once again, for general information on this forum: the original finish on the back of this mandolin does not appear to be either French polish or nitrocellulose but most likely some kind of oil-based varnish that is resistant to both ethanol and nitrocellulose thinners.

Hope this helps

Best Regards

Mike

[Paul Hostetter]

You refer to padded oil/varnish. I'm confused how is this different from the usual French polishing process?
I assume you're talking about the oil that's normally used in the French polishing process.

No, it's an entirely other substance known often as spirit varnish (though that is another confusing term). It's got a major component of oil, not just the dab of lube often found in padded shellac finishes. This topic has been discussed exhaustively on Mandolin Café. Check the archives there.

Gibson did not use rank-and-file French polish on its early instruments, a fact that becomes very evident if you try to remove that finish with alcohol. Or even acetone! (I have no idea how you managed to attack that A-3 with alcohol. Or, for that matter, why.) What is known is that the finish was applied by hand, and took awhile to dry, a fact that spurred Gibson to experiment with other finishes, settling finally on nitro lacquer. There is informed speculation that the varnish used then was this one:

It's a long-extinct product, but its composition was an oil blended with alcohol, which enabled quicker drying than a simple oil varnish. It's tough as nails, but softens easily with heat, even 80 years later. You can French polish over the old Gibson finishes easily, but in my experience, the only way to get them off is abrasion or really harsh chemicals which will trash the binding.

The above spirit or quick-dry varnishes came in lots of colors as well as clear and tinted transparent, it was also used as a car paint and general household paint. If Gibson used a black varnish, there is no reason they would have clear-coated it with anything. By the same token, if they were spraying nitro and wanted it black, they'd add the pigment to the lacquer and spray only that. Their early and late shaded or sunburst finishes were another issue, and entire other discussion.

Your description: "the original finish on the back of this mandolin does not appear to be either French polish or nitrocellulose but most likely some kind of oil-based varnish that is resistant to both ethanol and nitrocellulose thinners." is congruent with all I accept about early Gibson finishes. I wouldn't have thought one of the vintage of yours would still have that finish, but Gibson is nothing if not inconsistent!

[Mike Keen]

Paul

Thanks so much for the info, it seems I've been misinformed. The finish on the snakehead back certainly matches the charecteristic of the spirit varnish you describe. I'll check out the mandolin cafe archive.

At far as the A3. When I got it about a third original finish on the back had already been removed, probably by a belt buckle, and the rest was deeply scratched (and it had centre seam separation). The quickest option was to strip, fix and refinish. All I can say is it came off very easily with ethanol, I refinished with French polich and it now looks lovely.

Thanks again

Mike