Michael Darnton Violin Maker

Michael Darnton is a violin maker, restorer, writer and teacher who lives in Chicago...

More Ground Samples

more varnish and ground tests

In the last year my sample set has grown to about 40 tests. I don’t feel like I’ve solved anything, but from the samples, and my observations of old instruments, both in my hand and through the microscope, have given me a full set of criteria that a nice varnish ground needs to meet. At the top of the list are two things: sparkling wood fibers when lit from any direction, and maximum transparency–the ability for the microscope to see down through layers of wood cells into lower layers, which depends on very transparent wood structure. On older Cremonese violins that is much more the case than on anything new that I’ve seen.

Grinding Pigments

grinding tools

I’ve often used home-brewed pigments for varnish colors. When they’re finished, they are clumped, and sometimes gritty, in large pieces. To put them into varnish, one first needs to grind them to a fine powder.

When I worked at Bein and Fushi there wasn’t a lot of interest in raw pigments in the art world, so we had to look around to find dry pigments and the tools for grinding them. The hardest thing to get was a muller. Mullers look like upside-down mushrooms with flat tops, and are used against a piece of ground glass to break up pigment clumps and disperse them into varnish (or oil, if you’re making oil colors). The real grinding is done with a mortar and pestle: a muller isn’t a grinding tool as much as a mixing one, to make sure that every particle of pigment gets wetted with solvent or oil. [factoid: glass mullers show up on airport x-rays as completely opaque, and when the inspectors pull them out of your luggage, they still don’t have any idea what they’re looking at, of course…  which reminds me of the time I tried to take a chinrest key into a federal courthouse.]

The first one was so hard to find, that for a while after that I went hog-wild buying them whenever I saw them. They turned out to be easier to find in England, so I came back from several trips with more of them (I was particularly pleased by the little ones with knob handles which came from a wonderful artist’s store near the British Museum in London, Cornellisen’s –if you ever go to London, put it on your list of places to visit. Unlike the US where the exterior may not be mirrored inside, the inside of Cornellisen’s is even better than the facade).

I have more than the ones in the photo. The lean one in the back is the first one. The steel “muller” is actually a meat pounder I bought in a cooking store. I haven’t ever tried it, but for $6, I couldn’t resist. The big one in the front was a going-away present from the guys in the B&F shop, and has my name, all their names, and some other things sand-blasted into it (you can read “CHICAGO MICHAEL” on the top of the handle).

Mortars and pestles, which are necessary if you’re making pigments from scratch, but not always if using commercially-made ones, are easier to find, of course, so I have a variety of sizes, and one that’s just for a single one of my home made pigments that tends to stain everything it touches.

In Renaissance art studios, grinding pigments was childs’ work, and one of the primary jobs of the very young apprentices. It doesn’t take any skill, just lots of patience and time.

More Varnish Texture

German violin texture

This one’s interesting mainly because of its lack of great age: it’s from 1944, made in Hamburg, Germany; not a time and place you see many violins from. Usually I would associate this type of mud-crack surface with a soft varnish that’s been overcoated with something much harder (violating the painter’s fat over lean rule), where expansion and contraction of the softer underlayer has caused the over coat to break up gracelessly the way ice breaks up on water, but I’m pretty sure this particular violin has nothing over the original varnish.

In real life the surface of this violin looks leathery; it’s an attractive surface, but better in some places than others. Nevertheless, the whole effect is positive on a violin of a type that you’d normally see polished up like a bowling ball.

Experimenting with Ground Coats

bridges with ground testing

I started a series of tests this week, something I’ve always meant to do. I have a lot of scraps of wood with various things painted on them, but never have gone about it in an orderly fashion. Yesterday, I took a bunch of cheap bridges, scraped one side of each, and started putting a different ground coat on each one. Some dried right away, and I have some ideas about which of those I like. Others are going to take weeks or months to dry completely, but this time, when I look at them in a year, I’ll know what they are. (I have one little scrap of wood from about 20 years ago, stuck in a notebook, with nothing written on it, that if I knew what I’d done, that’s the varnish I’d be using.)

So far I’m testing Kusmi shellac, spray shellac, mastic, Ace spar varnish, oxidized turpentine, raw linseed oil, stand oil, propolis, gum arabic, and casein emulsion. As other ideas enter my mind, I’ll try them, too. Eventually I hope to have a sample of everything imaginable.

What started this whole thing was reading Jacques Maroger’s book, The Secret Formulas and Techniques of the Masters. It’s his analysis of the materials of the first Renaissance oil painters, and a couple of the things he mentions in the book made me wonder how they’d work as grounds. Maroger’s work is one contribution to how I originally got the idea for my uncooked mastic/linseed oil varnish (which is not the same as anything in his book), but I’ve never read his book before, because it’s hard to land at a price I could afford.

Modern Texture

A friend of mine brought in one of his older violins the other day. He uses a variation of my varnish that’s a bit more complex. His violin, which is around 15 years old and well-used, has acquired a really nice texture to it. It’s the most extreme on the ribs under the tailpiece, where it’s exposed to constant heat and moisture from the player’s neck:

violin texture

On the back, where the player’s shoulder touches, it’s less extreme, and still very attractive:

more varnish texture

I’ve never seen my own recipe do anything like this, so I assume the changes he’s made to it are responsible. As modern natural textures go (as opposed to the synthetic ones makers put on intentionally), it’s maybe one of the most attractive variations I’ve seen.

Texture

I have quite a few shots of varnish texture in my collection. This very attractive example is on a Gand & Bernardel violin from the 1860s.

Gand & Bernardel varnish texture

Sometimes texture only shows in protected or low spots, like the location above. This particular violin had it all over–here’s another shot:

Gand & Bernardel varnish texture #2

Printed Antiquing

I’ve seen maple curls that were painted on, but how about some stamped-on antiquing?

printed on antiquing

Varnish Pinholes

Guadagnini varnish pinholes

Old violins often have pinholes in the varnish. No one knows exactly how they got there, but they imply some things about how makers 300 years ago varnished, and what was important to them (pinholes obviously didn’t bother them much). This probably wouldn’t happen if the wood under the varnish was too well sealed, except we can see that sealer is there and that it has prevented the varnish from going into the wood, and pinholes aren’t compatible with that. It’s one of those little mysteries.

The violin in the photo is a very early G.B. Guadagnini from Piacenza, with bright red varnish. The size of the area in the photo is probably about 12mm across.