Violin Forum/Message Board

Geemac · Posted: Tue Aug 04, 2009 4:21 pm Post subject: I made my own varnish

DANGER - WARNING - If you are going to try this, do it outside. If you have an old electric hotplate use it as it does not have an open flame to set your work on fire. Use gentle heat and slowly warm the stuff. This is a very dangerous operation and you are completely responsible for your own safety. If you have any doubts about doing this, buy your varnish from Luscombe and stay safe.

Saturday, on a whim, I stopped into a tac (horse equipment) shop and asked for Venetian Turpentine. The kid behind the counter walked over to a shelf and got me a can. I thought finding the stuff would be difficult. Nope. It's made by Hawthorne. I believe it was originally used to harden the hooves of the Italian cavalry's horses back in the days of Strad et al and it still is used for that purpose.

Venetian Turps is mentioned in oil varnish recipes from those early days. It smells like regular turpentine, but is about as thick as molasses. I slowly cooked my first attempt, in my backyard, yesterday and threw in a few ingredients that I think the masters added to their varnishes.

To make it I ground some gum lac to a powder and added a bit of alcohol to disolve it.

Two parts gum lac to one part raw linseed oil. I guessed at the amount of Venetian turps to use. It was about the same amount as the gum lac. I added some alcohol and using very little heat and stiring the goo, I slowly cooked it outside on an old camping stove for a short while.

The cooked varnish in the jar has a medium dark brown color, but when it is spread thinly the orange of the gum lac shows through revealing an orange brown standard violin color.

Outside in the sun, I spread a bit on a test board and in an hour or so it was dry, but a bit greasy to the touch.

DANGER - WARNING - If you are going to try this, do it outside. If you have an old electric hotplate use it as it does not have an open flame to set your work on fire. Use gentle heat and slowly warm the stuff while stiring. This is a very dangerous operation and you are completely responsible for your own safety. If you have any doubts about doing this, buy your varnish from Luscombe and stay safe.

** Follow up the next day.

With the quick success I had on the test piece, I went on to put a coat on a violin top that I am refinishing. I put it in the sun for a few minutes then the clouds moved in. This morning it was sunnier and the varnish was almost dry overnight. Nevertheless, I put it out in the sun so that the molecular change could complete just in case it hadn't. I am pleased with the result and delighted with the varnish making process. However, please be careful if you plan to give this a try.

PS - Jesus is coming - Try to look busy.
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GeeMac

MANFIO · Posted: Tue Aug 04, 2009 6:16 pm Post subject:

Good! Have you followed a recipe? I think it's good following a recipe. Varnishes may be impredictable. They may look good today and horroble in ten years, sometimes even less.
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byacey · Posted: Wed Aug 05, 2009 11:59 am Post subject:

I was wondering what those fumes were coming from the southwest. Wink

I'm not sure if venetian turpentine is any better than using dry rosin. You have to cook all the moisture and volatile oils out of it for it to dry properly, essentially what rosin is. The longer you cook it before adding the oil, the darker the color will be.
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Bill

Geemac · Posted: Wed Aug 05, 2009 1:03 pm Post subject:

I was inspired by this web site. http://www.leroydouglasviolins.com/varnish.htm

But, being an experimenter Smile

I added salt, borax and epsom salts to the mix. They all disolved and are invisible in the varnish, but add some of the chemistry that is found in cremonan varnishes. Magnesium, sodium, clorine, boron which are found in Tony's varnish with an electron microscope (as noted on the web connection above.) Unlike Saint Albert, where it rains far too much for violin finishing, I can dry my varnish in sunny Spruce Grove.
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GeeMac

byacey · Posted: Wed Aug 05, 2009 7:54 pm Post subject:

Geemac · Posted: Thu Aug 06, 2009 8:44 am Post subject:

I put the minerals in before I cooked the varnish. The website shows a layer of minerals under the varnish, so a mineral mix was probably applied, dried and smoothed before the varnish was applied, but I thought I'd try it this way. You must remember that my violins are really ugly so I have no trouble trying out ideas or stripping them and starting again.

I did have a good result when I boiled the top wood before carving it. Next time I will carve it then boil it and apply a mineral layer. The thinking is that the masters in Cremona appled the minerals to prevent insect damage.

Research indicates that they used material called 'salt of gems'. I snooped around, thought for a while and deduced that salt of gems was probably epsom salt which is magnesium sulfate crystals. It was available in those days as was salt. You can see in the chart on the website that magnesium is present.

7 Aug 09 Did more digging into the probable source for the minerals found on Toni's violins. There is evidence of calcium hydroxide being used. This material is also known as lime, which when mixed with the pumice, the makers used, becomes a well known form of Roman cement that is still used to this day.

So far we have added Magnesium, Calcium, Sodium, Aluminum, Boron, Sulphur, Silicon and Clorine using methods and products that were available three to four hundred years ago.

With what has been uncovered so far we can cautiously conclude that likely some form of chemical paste or slury was mixed for each violin and it was used as an insect repellant and also served as a ground. But, as always, the proof is in the pudding.
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GeeMac