Stradivarius wood curing; a recipe for curing wood for exceptional musical instruments.

Fact 1: Stradivarius violins, from scanning electron microscopes, reveilles that most of the Plasmodesmata of the wood cell are missing. Plasmodesmata is the thinnest part of a wood cell and where nutrients and waste are passed to and from the cell.

In Italy, at the time Stradivarius (1644 to 18 Dec. 1737) was building his famous instruments, the major place to purchase wood, in his town of Cremonese Italy, an ocean port, was at the dock. The wood was sold from broken up rafts. What we are interested in is the journey of these logs from trees to market at this ocean port because it is important part of Stradivarius’ secret of curing his wood. The rafts of wood came from inland trees felled, skidded, with oxen or horses to nearest stream. A number of logs were bound together into raft. When several rafts were assembled they would be floated down stream to ocean. As note, the wood often spent several weeks in fresh water on its journey to the market. It has been conjectured that Stradivarius chose wood from high in mountains. This would yield wood with close growth rings and it would also add to the time the logs were immersed in fresh water.

Once the rafts reached the ocean they would be floated to a port for sale. Again several days in salt water. Then depending on how soon the wood was sold it could spend weeks in the salt water at the dock.

 

By immersing fresh cut wood in water, the ions and salts from once living cells would cause inrush of the water into the structure cells in an attempt to equalize osmotic pressures. As the logs soaked more and more of the cells would become saturated. This indicial inrush may have weakened plasmodesmata. or ruptured it. The remaining plasmodesmata when the wood went from fresh water to ocean salt water, causing the water in the cells to flow out of the cell to equalize the osmotic pressure rupturing the rest.

So the wood delivery system accounts for empty cell structure.

Fact 2: Stradivarius violins have six times more gold in the wood structure than would be accounted for in normal tree growth.

This is my conjecture that I will share with you. From my chemistry, I reason that the gold came from a process that Stradivarius used. I got out my CRC handbook and started looking for substances and crystals with gold that could be used to dry wood. I found: Aqueous Regis (gold of the king) A white hydrophilic salt. Kings like to keep this salt because when nitric acid is dumped on it, it will yield gold. Hydrophilic means it draws water into the crystal structure drying what ever is packed in the crystals. It is a great way to dry ocean-water-soaked wood. At these very high concentrations of salt whatever was left of the Plasmodesmata probably gave up. As the water moves out of the wood, in the drying process elements comprising the crystal would also move into the wood.

You probably will not be able to get this crystal because it is gold salt of cyanide! So Strad’s drying his wood this way also added a preservative in the form of cyanide! So do not chew on Stradivarius.

My recipe for curing wood:

I first experimented was with Birdseye Maple in very small quantities (strips big enough to make banjo bridges ¾” X ¼” about 12” long). I found a one-piece cutting board of Birdseye Maple in a department store. I bought it, and proceed to cut it into strips, for banjo bridges, to the dismay of my wife, who though I had bought it for our kitchen. I soaked part of the strips in rainwater for two weeks. The other half of the cutting board strips I placed attic of my house. We had an old fashion roof catch system to a cistern; distilled water or reverse osmosis water would be equal or better. You can get it from a store or from your kitchen sink’s special faucet. You would not be getting minerals and salts from my roof shingles. During that time the wood soaked, a scum appeared on the surface of the water, oils resins or whatever else came out of the wood and floated to the surface. Perhaps other things settled out to the bottom of the capped PVC pipe I used. These strips were of cured wood.

1. Soak your wood in pure water for two weeks

After the two weeks, I poured off about half the water into a pail and added rock salt stirring it in until I had just few crystals that would not dissolve. Then I poured the salt water (brine) and the crystals back into the PVC pipe. The rock salt was left over from making homemade ice cream. For the next several each day I repeated the procedure until the salt started to crystallize at the surface of the vertically standing PVC pipe. I let the wood strips sit in salt saturated water for another week.

I would recommend water softener salt instead or rock salt. It is very much cheaper and just little less pure than rock salt.

2. Daily add salt to the water by pouring half off and mixing in salt and pouring it back in your vessel.

I decanted the brine. (For those of you that were my old neighbors in rural America) I poured off and disposed of the salt water that the wood was soaking in.

3. Pour off your salt water.

I packed the strips of wood in desiccating silica. I was an Aircraft Mechanic (the old timers term for Aviation Maintenance Technician). Almost all the important aircraft parts are and were packed with bags of these wonderful crystals to keep moisture out. Some engine crates would have as much a 10 pounds of these wonderful crystals. Rather than disposing of these crystals, I took the bags home with me. I would cut the bags open and spread the crystals on a cookie sheet and dry them in my oven in the evening after supper. In a garbage bag in my attic, I laid down a layer of these crystals and then lay the strips of wood from the brine on the crystals. Then I covered the wood strips with crystals. Adding layers. I had about three layers. I closed the bag with a twist wrap from grocery store next to set of strips that were in the attic all this time (The Control).

4. Pack your wood in drying crystals for drying in sealed atmosphere for about three weeks.

For the first few days I would open the bag and take out all crystals and dry them in the oven. As the wood dried I could go several days without drying the crystals. At the end of three weeks I removed the strips from the bag and they were considerable different from the strips next to the bag from the same board. They were lighter in weight (noticeably by holding them). They were lighter in color with more defined grain. In making a banjo bridge the ones from the bag were far superior.

This method works well with thinner woods, however I decided to try it with heavier woods.

We were cutting hedgerows around local fields and I cut down many beautiful Black Cheery trees. Most became firewood for the impending winter for me but some of more beautiful pieces I saved to build banjoes. I took a 2” X 14” X 14” slab and immersed it, treating it like the smaller strips, in a plastic garbage can. I brined it. I added considerable time to process because of the thickness of the wood about time five times. When the process was complete there was no checking or cracking in the slab. It had a noticeable ring over air dried Cherry.

I will leave you to decide what you will do.

John Alden Robinson

jrobinson@maliposamusic.com

Maliposa Music

17415 N. 75 Ave

Glendale, AZ 85308

Maliposamusic.com