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Alcohol soaking method
for drying green wood
(90% denatured ethanol)
 
During the tests, please write down the wood species and take pictures that will be added to the Web Gallery in order to create a database on the method taking into account the differences due to the various wood species. Thank you.

Hello everybody, I'm beginning to test American wood turner David R Smith's method of drying green wood. I want to share this method with you and collect returns of experiments.

The process is to soak the wood blank in 90% denatured ethanol.

Water and alcohol being miscible, it seems that there is an exchange between the water contained in the green wood and the alcohol in the container until an equilibrium is reached.

Drying is then made easier because the mix water/alcohol evaporates faster from green wood.
 
This might be a lead!

On Spruce:
W. Liese, at the Institute of Applied Mycology and Wood Protection at Hann.-Münden, which is under the direction of H. Zycha, has carried out investigations on impregnation with oily wood preservatives. He found that the poor absorption capacity of spruce is due to an irreversible closing of the tracheids. In air-dried wood the closing of the tracheids can he arrested or relaxed by various treatments. In green wood, preliminary alcohol or acetone applications, keep the tracheids open, and the timber can be fully impregnated with oil.





Here is his method
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- Roughly turn a blank with a thickness of:
- 10 to 13 mm for a diameter up to 16 cm:
- 16 to 25 mm for platters up to 40 cm in diameter:
 
- Put the blank in a plastic container (preferably with a lid) and fill it with enough alcohol to cover the blank completely.
 
- Let it soak for 24 hours to insure thorough penetration.
  
- Take the bowl out and let it drain off for an hour.
 
- Wrap the outside of the bowl in heavy paper and secure it with masking tape. Put it upside down on a grid.
 
.  
According to his theory, wrapping the outside of the object causes the inside to dry and shrink first, this puts strain on the outside and compresses it. This force minimizes cracking during the drying process.
 
- In order to check when the object is dry, it must be weighed to a gram every day with a precision scale.
When there is  no change in weight for 2 to 3 consecutive days, the object can be considered dry.
 - You will notice it takes 5 to 6 days for small 1 cm thick objects to dry. It should take around 10 to 15 days for larger objects to dry and 3 weeks to a month for objects with a narrow neck.
The rest of it coming soon....
 
The same alcohol can be used several times as long as the alcohol concentration remains above 60%.



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