Michael_Molnar

The Strad would rightfully have a fit with people bypassing their subscription. Google “bone ash”. Also, look into sciencedirect.com and Elsevier Masson.

Friends, you are going down a rabbit hole by not having read the article. However, I did find their original research paper: Stefan Zumbuhl, Balthazar Soulier, Christopher Zindel. ”Varnish technology during the 16th - 18th century: The use of pumice and bone ash as solid driers.” Journal of Cultural Heritage 47 (2021) 59-68. I subscribe to ScienceDirect.com to read this.

I now have had time to read The Strad article and like it. The researchers corroborate other work detecting burnt (calcined) bone and pumice as varnish driers. This could be an explanation of the rubble detected in some varnish systems. I really like how they presented the ancient varnish references by listing them chronologically. This makes a strong case for the researchers. However, the varnish driers have only a slight effect on what we see today because they are now practically invisible. This is only part of the saga of Cremonese varnishing.

I just got my October 2021 copy of The Strad and saw "Beneath the Surface" by B. Soulie, S. Zumbuhl and C. Zindel. They examine the minerals found in Cremonese varnishes and grounds. I am not done reading it but wanted to make this "heads up". It looks like some nice work.

BTW, when using measurements, use weights, preferably metric.

I add a lime slurry. It is mostly water. I slowly squirt it into the hot varnish while stirring.

Agreed. One cannot quantify artistic merit.

I have argued that the next step in understanding violin acoustics lies in Artificial Intelligence (AI) which uses neural networks to make predictions. A few months ago on a trip to California I discussed this idea with a Silicon Valley computer expert, Luis Trabb Pardo. He opined that the issue was not just simulating the violin but more so the listener. Well, as it happens, the September issue of The Strad has a timely article, Intelligent Design by Sebastian Gonzalez. The last paragraph rings loud and clear with this sentence, "So understanding what’s so special about Stradivari’s violins is not something that can be accomplished without studying the biological response music produces in human bodies." The article explains a first step in simulating violins using neural networks. I think we can agree that simulating the entire violin, not just components such as the free plates, must be the objective.

In your capacity as a legendary maker have you tried that fingerprint test?

Yes, but I think a lean varnish wears faster than a fat one.

I find that letting the protein ground be the wetting interface introduces adherence issues. The thin clear varnish layer does a nice solid interface as long as it dries thoroughly. Aging is indeed involved. Keep in mind that all natural organic materials degrade to one degree or another.

In a nutshell, I think John’s photos show stained wood. A stain infuses the wood structure enhancing its visibility. A layer of colored varnish alone cannot recreate this.

@Michael Szyper , I guess you also know that the washed raw oil must also then be heat treated before being cooked in a varnish. BTW, I forgot to say that salt is added to the wash water. Why anyone in this day and age would still process raw linseed oil, is beyond me. Try using Varnish Maker’s Linseed Oil at WoodFinishing Enterprises.

Add coarse sand to the water and oil mix. Shake like hell. Let it sit for 10 minutes. Pour off the clean oil.

Right. Artists have no issue with a little wax in their oil.

Washing the oil removes waxes that are indeed sticky. However, I think most of us use clean, washed oil. Hope I’m not being presumptuous.

Great photos. Thanks.

@jacobsaundersis the expert to contact.

You know, I too am thinking along those lines.

Here is the same stain off steroids, namely toned down (no pun.) Chemically the same but I applied it in many diluted coats to work it into the flames. Potassium caseinate overcoats the stain and contains some talc ground that researchers think is present. Optically, the caseinate wets the stained wood making it "pop". The talc rubble does nothing but fills voids which is one purpose of a ground, namely smooth the surface. On top of this I put on a very thin coat of a clear varnish that has just a hint of green meeting B&G's findings. My green tint might be too insipid. I think it does nothing. I took this photo under a hot fluorescent ceiling lamp. The paper is white, so you should adjust your monitor to make it pure white.

My findings agree.

I was a friend of Merle Frantz. I too am surprised that the business closed after he died. It was a good size operation. Anyhow, I too recommend John Tepper in Oregon. BTW, I do not use BigLeaf maple, FWIW.

This is the precipitate from skim milk treated with an acid such as vinegar. It is the simplest form of cheese that is dried and packaged.

I should have given the entire recipe which shows that the salt concentration is not ridiculously high. Sorry. 500 ml distilled water (this avoids dissolved minerals like iron) 14 g KOH (for a 0.25 M solution) 45 g acid casein (slowly dissolved) 80 g table salt as a preservative.

I agree about calcium; however, we could be wrong. In my case, it would not be the first time.