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I've seen old time sign painters use it for gold leaf signage; might check sign painters supply houses

Filippo: Gold leaf sold at art supply stores may be what you are after. Very hard to handle and usually applied with a flat brush via static,I think. Sizing is brushed on object to be coat and gold leaf applied and allow to dry then buffed all over to remove excess.Again I think,never used it myself.
Tom

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A person who has never made a mistake has never made anything!!!

If you are looking for gold in 'veneer/purfling thickness' then jewellery supply springs to mind. If you have a serious jeweller craftsman nearby, he/she will have a hand rolling mill and can probably make you what you need.

I don't think gold leaf will be thick enough to be visible viewed on edge. I've only ordered gold wire from them (side dots), but I've had good luck with this company:

http://www.pasternakfindings.com/catego ... elry_strip

They have .080"x.008" strips in various karats.They're in Israel, but when I ordered last, they had the best price I could find. They have a toll free U.S. number.

Depends on what you have in mind, Filippo. If you mean gold-colored metal foils, that's one way to go but they tend to oxidize over time and are not very durable. You can find these at art and framing supply stores. If, on the other hand, you mean real gold, I would urge you toward 23.5k yellow foil for keum boo as it will look better and stand up to greater wear.

http://tinyurl.com/KeumBooFoil, or
http://tinyurl.com/22point5k

But if you're wanting thin, elegant bands of gold between layers of veneer, you would need something at least as thick as cloisonne wire, and perhaps twice that. Cloisonne wire is very thin (but highly visible) when viewed on edge and is rectangular in section, running .0035" by .06". As cloisonne must be 24k so as not to oxidize during enamel firings, it's not necessarily your best bang for the buck at $38/ft currently, as most would be hidden below the surface.

http://tinyurl.com/CloisonneGold

I'd still suggest a high karat gold, however, for richness of color and resistance to oxidation, so 22k would be my recommendation. Certainly nothing less than 18k, which is considerably springier and less rich looking. An advantage of 22k is it's workability. For example, you could easily flatten 22g wire from .025" to half that and get it to behave in a channel with little waste below the line of vision. You can get 22k yellow gold wire from some non-wholesale jewelry suppliers, such as Rio Grande or Otto Frei.

http://www.riogrande.com/
http://www.ottofrei.com/

Now if you want a wider band, that's doable, too, and might cost about the same. You would simply inlay the flat strip into a very shallow channel.

None of these things are terribly challenging (even kids can do it) nor involve special tools - your fingers, a small stick, cotton swabs and an X-acto knife would do the job. Maybe you can elaborate on what you envision and I can be of greater help. How many bands? How wide? And so on. Feel free to PM me if you like.

Funny this should come up as I was just talking about making a rosette incorporating Etruscan granulation.

Oh, that's easy. What you need is tombac, or rich low brass, (also called Merlin's gold, jeweler's bronze, et al), which is 85% Cu and 15% Zn. It's a good match for the CuSn15Fe1Ti0.1, which I've been considering, as well. Both are in the 10k to 14k color range. It's cheap and easy to work in the thicknesses you're talking about. A 6"x6" sheet in 24g (0.020") is a whopping $3.60.

Problem is, if you wish to avoid breaks in your strips you'd need longer sheet, so... the cheapest solution would be to flatten some 20g wire, ideally with a rolling mill (and no, don't flatten it with the pasta press), but you can hammer and sand it into submission and it'll only set you back $3.50 for 20 feet. If I had any I'd just roll it out for you, but it's been years since I've seen the stuff. Metalliferous carries it though.

http://tinyurl.com/RosetteGold

David

[Just a note, if someone offers you tonval, from a craft jeweler's supply, be aware it has lead in it.]

RioGrande has 24K gold bezel wire that's .010" X 1/8" but can be ordered in special widths or use to be able to order . It makes for nice side purfs or lines. Have you considered gold MOP for the rosette?
I'm also interested in whether the brass will tarnish. The gold won't. I have a brass penny whistle that is lacquered and it has tarnished.

Filippo,

To answer your first question, surprisingly, tombac does not easily tarnish as one might suppose, and if well sealed is usually not a problem. The adverse conditions that would bring it about might well be as deleterious, if not moreso, to the rest of the guitar. I have seen pieces that were older than I am in still-bright condition. Also, most boulle has endured under its original FP and would be rather more susceptible to tarnish and patination than tombac.

CA and/or epoxy would both be good protective films when cured but might initially react with the metal, so test first, of course. I've seen brass and commercial bronze under CA that looked fine, though, so probably not an issue.

As for slicing long binding strips, a large paper cutter with a well-sharpened blade will do the trick up to about 22g, although 24g might be more forgiving. Nick the leading edge before starting the cut and then maintain a steady and somewhat fast stroke. Sometimes backing it with a very thin and hard tracing vellum seems to help with less-sharp blades but try it without first. Edge distortion is minimized compared to other methods, although one can (and one has) cleanly cut long metal strips with a sharp chisel. The technique here is to sandwich the sheet between two wide strips of mild steel or brass, one higher than the other, then sliding the chisel corner along the ledge until the deed's done. One develops a feel for starting the cut and continuing at a steady speed. I like to pull the chisel toward me, but it works either way. It dulls the chisel corner but gets the job done. Shears distort, saws are slow, unless you have a micro-TS.

As for flattening round stock, it's easier to grab a couple different gauges of wire, whack 'em, mike 'em, and see what you get rather than calculate. If it looks right, you're there.

I love this stuff.

David

You're absolutely right, Chris, 24k will simply not tarnish. I work only in high karat golds, almost exclusively 22k, which is for all practical purposes impervious, as well. I alloy an analog to alluvial placer to replicate ancient Mycenaean, Etruscan, Egyptian gold techniques (loop-in-loop chain, granulation, and so on) and have yet to see it discolor or dull. No brass or bronze around my shop. Fine silver's okay, though, too.

I'm not too sure now about that being 24K it might be 14K but it was about 8 years ago. At the time it was $300 for 5' enough to do side purfs on top and back. So the Tombac will be a great savings if I have the need for it on a future project if I want a substitude.

I have a love/hate relationship with gold foil. Never used it on a rosette or in purfling, but have done several picture frame fixes with it. For me it was hard to work with. Very thin, very fragile. But that might be just me. As suggested, you need real gold foil and not simulated leaf. The real stuff will not tarnish, and if protected will last a very long time. The West Virginia Capital Building Dome is covered with Gold leaf. Pretty stuff.

Well, gilding capitol domes is over-the-top (groan).

While I've seen other gilt musical instruments, most are gold leaf rather than wire or sheet inlay. Obviously, harpsichords and other early keyboard instruments come to mind. One I used to play (and tune, grrr) had shell gold (finely powdered), applied over glair then burnished. I've used shell gold on vellum to highlight raised letters as it can be left more matte than leaf, which is more to my taste.

Of course, wire inlay into wood is entirely doable but it helps to use 24k or a soft enough alloy to avoid chipping or damaging the inlay channel, which is usually undercut with a graver to lock in the wire. Filing and scraping it flat completes the process.

The Pimentel jazz classical with 14k wire inlay rosette and tie block, doesn't appear to be done this way as the thin outlining veneer strips obviously wouldn't stand up to punch setting or burnishing pressures, so I'd assume it's strip inlay. I'll also assume the photograph doesn't do it justice. The close-up of the rosette looks a bit uneven, especially in the 11 o'clock position, but maybe I'm too picky, heh.


http://tinyurl.com/14kWireInlayRosette

http://tinyurl.com/PimentelNylon