I've been given a fiddle in the white, and am just starting to investigate the mysteries of violin varnish. I've done a good bit of setup and minor repairs over the years, but have deliberately avoided messing with finishing.
I understand the idea of sealing the pores, so the varnish doesn't soak into the wood, but when it comes to fiddles, everything sure does tend to go off in the direction of magic and alchemy whenever them that know start talking shop...
A lot of folks recommend something protein-based, often casein, giving a recipe based on milk powder.
- - Isn't Elmer's® casein glue? If it is, could it be used (diluted) as a ground (with or without pumice, fuller's earth, or whatever filler added)?
-- Wouldn't thin hide glue work?
-- What about dilute shellac+mineral filler? (I've seen just a thin coat of shellac recommended, but others say it's not flexible enough).
-- Any other ideas?
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Originally posted by Dan GellertI've been given a fiddle in the white, and am just starting to investigate the mysteries of violin varnish. I've done a good bit of setup and minor repairs over the years, but have deliberately avoided messing with finishing.
I understand the idea of sealing the pores, so the varnish doesn't soak into the wood, but when it comes to fiddles, everything sure does tend to go off in the direction of magic and alchemy whenever them that know start talking shop...
A lot of folks recommend something protein-based, often casein, giving a recipe based on milk powder.
- - Isn't Elmer's® casein glue? If it is, could it be used (diluted) as a ground (with or without pumice, fuller's earth, or whatever filler added)?
-- Wouldn't thin hide glue work?
-- What about dilute shellac+mineral filler? (I've seen just a thin coat of shellac recommended, but others say it's not flexible enough).
-- Any other ideas?
I'm with you on trying to do away with magic and alchemy. I always use a thin coat of fairly thin shellac which works fine for whatever you put over it. I don't understand why it wouldn't be flexible enough, or what that's supposed to mean. I've heard that thin hide glue works, and I'm sure other things work as well. The only reason I see for dealing with convoluted recepies is if you like that sort of thing.
That’s a tough one. There are so many options to choose from. I’m not a varnish expert, but here is how I would paraphrase things:
There are two functional parts and sometimes one aesthetic part to the ground. One can start by lightly staining the wood with something like linseed oil, gamboge, tea, coffee, nitrates, vegetable dyes, or the horse urine/feces mixture that’s popular lately. This is done just to make the wood look less bright white so it doesn’t look so brand new. After this is done (if you decide to use a stain), something is used to fill pores so they won’t absorb color later and make the wood look “burned.” Pore fillers are supposed to fill pores but not penetrate too deeply into the wood. Once the pores are filled a sealer is put on top to make the ground more permanent and lock the pore filler and stain in. Varnish wears off over time with heavy use and abuse but you want your ground to last, even if the varnish gets stripped.
Some grounds take care of more than one of these things or all of them in one shot. In Mittenwald it was the practice to liberally coat a white violin with linseed oil and then hang it up to dry for a year for the next class to varnish. The oil hardens over time and can make instruments hard sounding and it can go right through the wood. Be careful.
Hide glue has been used in the past. Glue does seal and fill if it’s a good viscosity. It does make instruments very hard and harsh, though, so it’s generally not the favored method.
Shellac is a popular and easy choice. Just recently I read a Maestronet post by Jackson Maberry about shellac. He recommended using thick shellac, not thin, because thin shellac is full of alcohol and will penetrate too deeply. I’ve used shellac and been happy with it recently for some white violins.
Casein is quite popular, especially after Roger Hargrave wrote about it years ago. I would not recommend just using glue though. I’m not sure the formula for Elmer’s would be appropriate for violin coating and I think it would likely be too much like plastic. A colleague of mine made some for his own making and quite liked it. I haven’t tried it myself but I’m curious.
Hargrave has written about the slaked plaster ground in his Making a Bass thread/book. This ground has gotten a lot of attention and has inspired a lot of makers lately. I’ve been thinking about trying it on a white violin if I ever get the time.
Egg white is a good ground that I’ve heard a lot of people recommend. It’s an easy ground to prepare and goes on well without going too deep from what I gather.
Just like varnishing, there are many ways to arrive at a good result, and a group of makers using the same system will get varying results. I would prioritize finding something that’s user-friendly and not too toxic to start and making sure it doesn’t penetrate too deeply into the wood.
I've seen that equine poop and pee thing referred to a lot, but always in the sense of "you wouldn't believe some of the stuff the old masters used to do." Are you saying there are lots of folks actually staining new violins that way now?
The ingredients certainly are plentiful in my neighborhood, but coffee sounds a whole lot more appealing to me.
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Originally posted by Dan GellertI've seen that equine poop and pee thing referred to a lot, but always in the sense of "you wouldn't believe some of the stuff the old masters used to do." Are you saying there are lots of folks actually staining new violins that way now?
The ingredients certainly are plentiful in my neighborhood, but coffee sounds a whole lot more appealing to me.
Joe Thrift, who spent some time with Roger, has been promoting that formula in his violin making workshops over the last several years. The "Roubo sauce," as it's been nicknamed, is based on an old formula that was in use centuries ago for staining wood. No one really knows if it was actually used in violin making, but it was a recipe with which woodworkers may well have been familiar in the 1600s. But in any case, I think the practitioners have decided that they are less interested in whether it was used by the Cremonese makers than in the appearance they can get using it. As I understand it, the formula has been chemically analyzed so that it could be synthesized without the need of a horse.
I looked up Elmer's. It originally was a casein glue, but the current formula is synthetic.
Also, it seems casein glue is a whole lot easier to make than it looked from the recipes those fancy luthiers were suggesting.
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Originally posted by Dan GellertI looked up Elmer's. It originally was a casein glue, but the current formula is synthetic.
Also, it seems casein glue is a whole lot easier to make than it looked from the recipes those fancy luthiers were suggesting.
A colleague gave me a recipe for making it. It wasn't complicated at all, I just haven't had the occasion to try it yet.
A buddy sent me a recipe for homemade "hide glue" that is essentially gelatin. Could it be used in this instance as sealer? Probably hard and harsh too though
https://blog.lostartpress.com/2023/09/26/how-to-make-our-glue/
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Originally posted by ChickenManA buddy sent me a recipe for homemade "hide glue" that is essentially gelatin. Could it be used in this instance as sealer? Probably hard and harsh too though
https://blog.lostartpress.com/2023/09/26/how-to-make-our-glue/
Gelatin is used as a sealer often. I'm not sure why the salt is added to the recipe linked, so I'm not sure about its application instead of regular gelatin, but it doesn't sound too substantially different. I do think glue sealers can make the wood too hard, but if they're applied in such a way as to seal without hardening the wood too much, they can work reasonably well.
I bought a Vicks brand vaporizer. For humidification in the winter. The top of the vaporizer stated,"if your water doesn't vaporizer easily, add a bit of table salt."
I had to do this. Just a bit of salt makes a great difference. This property could be the reason to add salt.
I attended a varnishing workshop ages ago where we used water glass and then oil of turpentine. The water glass was in flakes and we added water to make a sludge that we brushed on and then mostly rubbed off. The idea was to get the fine mica into the pores and then seal it in with oil. Although the instructor got a passable result, ever my single student had issues with it. The flakes just seemed to remain no matter how careful one was to try to get rid of them, and as we brushed on coats of varnish, the brushes were constantly getting polluted. I ended up stripping the violins I brought. Perhaps if the mica were ground with a mortar and pestle it would yield better results, but I certainly don’t plan on using that method on a nice instrument again any time soon.
I would recommend egg white, gelatin, or thick shellac for getting started. Or you could always invest in a system like Old Wood, Violin Varnish Cremona, or Joe Robson’s varnish. They’re costly but have a good track record.
I think I'll pass on the poop and piss sealed fiddles, thank you very much.
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Originally posted by wrench13I think I'll pass on the poop and piss sealed fiddles, thank you very much.
When I was working at my first shop, Roger Hargrave posted on Maestronet about learning from the folks at the Aubert factory that they used rabbit urine to color their higher level bridges. This led my co-workers to seek out and obtain a gallon of rabbit urine online (how on earth was it collected?). When it arrived it was opened, and the smell was so potent that everyone agreed it needed to be stored in a shed outside. According to information someone had found, the smell was supposed to dissipate after a few weeks, but that did not happen to this jug. It stayed in that shed for years until it was thrown away long after the shop moved to another location and it was never used in any experiments.
As far as I can see, food gelatin is exactly the same as hide glue, just finely ground vs pellets. People have built guitars using plain Knox gelatin. Perhaps the fine powder makes it suspend slightly differently in water, but for gluing purposes, I believe it is just hide glue.
Maybe in a decade or two when I have made my own instrument with jello, I can report back for certain.
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Originally posted by amwildmanAs far as I can see, food gelatin is exactly the same as hide glue, just finely ground vs pellets. People have built guitars using plain Knox gelatin. Perhaps the fine powder makes it suspend slightly differently in water, but for gluing purposes, I believe it is just hide glue.
Maybe in a decade or two when I have made my own instrument with jello, I can report back for certain.
Not exactly. Gelatin is much more refined than hide glue, which is why it's so much clearer. It's a bit like apple cider vs. apple juice--both are made from the juice of pressed apples, but the products are not quite the same.
Gelatin can be used for many things, but it's important to make sure it's strong enough for the intended purpose.
Strength of Knox gelatin is 225. Typical violin hide glue is 192. Same range. Strength is not the question. Other properties would be untested, like brittleness/stiffness and longevity.
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Originally posted by amwildmanStrength of Knox gelatin is 225. Typical violin hide glue is 192. Same range. Strength is not the question. Other properties would be untested, like brittleness/stiffness and longevity.
General purpose hide glue for woodworking is 192 to 210 or so, but 315 is often used for instrument making. Bloom strength is one factor, although not the only determinant. Some makers use 192 for the longer working time.
A colleague told me that his shop used to repair cracks with gelatin so that the glue lines were even less visible. As an experiment, I ordered some to try and glued an open seam and a fingerboard with it. While it initially seemed fairly stable, both glue joints failed within several days. It took a lot more gelatin than expected when making the batch to achieve a consistency that passed the finger test. Regluing both joints with hide glue was successful and lasting. I kept the jar of gelatin to try for other purposes, but I wouldn't trust it for anything structural after seeing it fail.
