What the Heck is Stabilizing Wood?
What is stabilizing wood. It is a process to help wood reduce seasonal movement and it’s reaction to changing humidity. Sometimes the wood movement in certain woods would actually spider crack the Cyano-acrylate (Superglue) finish I applied before I started stabilizing. The stabilizing also gives wood a higher density which helps with the turning of the wood and the tone of the calls. Wood stabilizing is also used in knife making and pen turning.
To begin the stabilizing process, the wood blanks need to be dry, very dry. The wood blanks have been cut, pre-bored and acclimating in the shop for a while. The call blanks are put in the oven for 24 hours at 200 degrees to remove the remaining moisture. After they are out of the oven they are either put in the vacuum chamber or put into a zip lock bag so moisture doesn’t equalize back into the wood..
The vacuum chamber is a sealed acrylic box that I hook a vacuum pump to. The whole idea is to remove all the air from the wood call blanks as much as possible. The blanks are stacked in the vacuum chamber, weighted down and then a heat activated resin (Cactus Juice) is poured over the blanks so they are submerged. The vacuum pump is turned on and the air begins to be sucked out of the chamber. The resin has a very thin viscosity (almost like water). The vacuum sucks the air out of wood creating bubbles that rise to the top, out of the resin and then sucked out by the vacuum pump. After about 1 1/2 – 2 hours, most all of the all the air is out of the wood. The vacuum is released and the resin submerged wood takes in the resin where the air was before. I usually soak the wood in the resin for at least double the time that it took to get the air of the wood. Sometimes I’ll soak the blanks over night with especially low density wood. When the wood no longer floats, that indicates good resin saturation into the wood.
Since the resin is heat activated I need to bake the blanks again to set the resin within the blank. The call blanks can’t directly touch each other or they will permanently stick together when the resin hardens. I let the excess resin drip from the blank before rolling it in aluminum foil. I can put multiple blanks into one piece foil by simply rolling them up without touching another blank. I put the foiled blanks back into the oven at 200 degrees for about 2-3 hours to activate the resin. After the blanks are baked and cooled, I simply peel the foil of the the resin infused blanks and run drill bit to clean resin out of the drilled holes.
I can feel the difference in the weight of the call blanks after stabilization. The stabilized call blank now have the density of other wood I don’t have to stabilize. The palm woods are very stringy and tear out severely when turning before stabilizing. After, they turn really smooth and the waste comes off as dust instead of chunks and strings. I have never had a stabilized call spider crack the finish. A totally worthwhile step in building quality calls with beautiful but lower density woods.
If you are interested in wood stabilizing in your own shop, contact Curtis at http://www.turntex.com/. He can get you setup and answer all your questions.