• Beware of Counterfeit Woodturning Tools (click here for details)
  • Johnathan Silwones is starting a new AAW chapter, Southern Alleghenies Woodturners, in Johnstown, PA. (click here for details)
  • Congratulations to Paul May for "Checkerboard (ver 3.0)" being selected as Turning of the Week for March 25, 2024 (click here for details)
  • Welcome new registering member. Your username must be your real First and Last name (for example: John Doe). "Screen names" and "handles" are not allowed and your registration will be deleted if you don't use your real name. Also, do not use all caps nor all lower case.

DNA for drying greenwood Vacuum or Pressure?

Joined
Jan 23, 2011
Messages
20
Likes
0
Location
Round Rock TX
I have read several articles about drying green wood with DNA. A few articles mention using a light vacuum to improve the process. Does the vacuum improve the penetration of the DNA into the wood fibers? Would pressurizing the container have the same effect?

Great forum BTW, great posts and a lifetime of learning contained herein.

thanks, John Wallace
 

Bill Boehme

Administrator
Staff member
Beta Tester
TOTW Team
Joined
Jan 27, 2005
Messages
12,886
Likes
5,168
Location
Dalworthington Gardens, TX
Website
pbase.com
There are some incorrect assumptions being made by those who believe that ethanol accelerates the drying process to any significant extent. A more accurate description of the mechanism is that the alcohol helps to soften the lignin enough to relieve some of the stresses that develop as water leaves the wood and it begins to shrink. Back in the early 20th century, there were several patents granted that involved using alcohol to accelerate the time to market when processing dimension lumber. None of the alcohol treatment methods proved to be commercially competitive with kiln drying. The claims that the patents were based on did not include faster drying. Instead, they were based on a method to stabilize the wood against things like checking, twisting, bowing, winding, and shake. The idea was to deliver stable wood more quickly to the customer regardless of its MC. Once it was stable, then it could air dry at the lumber yard.

Personally, I feel that soaking rough turned bowls in alcohol is a waste of time and money -- not that it does not help to reduce warping and cracking, but that there are much cheaper ways to accomplish the same goal and the small amount of time saved is offset by extra work.

As far as your question is concerned, a pressure vessel would be very expensive. If you already have a vacuum pump then making a vacuum enclosure is fairly simple. You could use the same type materials use for vacuum veneering. However, given the limited benefit of alcohol soaking, I would suggest that doing anything beyond just throwing the wood in a bucket of alcohol would, by comparison, make a WPA project look like serious business.
 
Back
Top