dhallnc
Member
What is the use of each as wood turning goes?
I won't go near any raw wood with DNA due to the fact that it is hygroscopic (it means that it absorbs moisture , even from the air ) . The last thing you want is to get water on bare wood then try to put a finish on it . You trap the moisture under the finish and end up with a cloudy finish , been there done that . Acetone is not hygroscopic so it is safe to use on bare wood . What ever you use make sure to give it time to evaporate before you put your finish on .
CA accelerator is the best thing to use to wipe down your blanks but gets expensive so acetone is the next best thing .
Thanks, I do want to make some of my own pen blanks from trees on our land. I'll try that.As Butch said Acetone is great for cleaning your blanks just before finishing.
DNA is great for speeding up the drying process of green wood. I have rough turned bowl blanks minutes after cutting the tree and soaking them for a day in DNA. I take them out and wrap them in brown paper with a small hole in the top side of the bowl and then place them upside down on a wire rack for about three weeks. Unwrap and finish turn the dry blank.
You could do the same basic thing for pen blanks if you cut a tree and wanted to turn a pen out of it.
Bruce
As Butch said Acetone is great for cleaning your blanks just before finishing.
DNA is great for speeding up the drying process of green wood. I have rough turned bowl blanks minutes after cutting the tree and soaking them for a day in DNA. I take them out and wrap them in brown paper with a small hole in the top side of the bowl and then place them upside down on a wire rack for about three weeks. Unwrap and finish turn the dry blank.
You could do the same basic thing for pen blanks if you cut a tree and wanted to turn a pen out of it.
Bruce
This works well for the very reason you don't want to use it on an already dry piece of wood . The DNA absorbs allot of the moisture in the wet wood then evaporates taking most , but not all , of the water with it leaving your blanks at about 20% . To avoid finishing problems you want small pieces like pen blanks to be under 10% (6% to 8% is best) , however you have to remember the wood will gain moisture content from the air it is stored in , so too dry will cause wood movement problems like cracking and twisting . Always let your blanks come to equilibrium with your shop , this can take a couple of weeks .
A word about oily woods , DNA does take the oil off the surface of the blank but replaces it with more moisture . In most cases this small amount of moisture don't matter but to be safe Acetone removes the oils better then DNA without adding any moisture so it is a better choice for this purpose as well .
This works well for the very reason you don't want to use it on an already dry piece of wood . The DNA absorbs allot of the moisture in the wet wood then evaporates taking most , but not all , of the water with it leaving your blanks at about 20% . To avoid finishing problems you want small pieces like pen blanks to be under 10% (6% to 8% is best) , however you have to remember the wood will gain moisture content from the air it is stored in , so too dry will cause wood movement problems like cracking and twisting . Always let your blanks come to equilibrium with your shop , this can take a couple of weeks .
A word about oily woods , DNA does take the oil off the surface of the blank but replaces it with more moisture . In most cases this small amount of moisture don't matter but to be safe Acetone removes the oils better then DNA without adding any moisture so it is a better choice for this purpose as well .
Not quite true. Denatured alcohol is 95% ethanol denatured with 5% methanol to make it undrinkable and legal to sell without all the taxes.
Both alcohols dissolve water diluting it's purity. If your alcohol is leaving 20% water it probably means your supply is nolonger dry. As the alcohol evaporates it leaves behind the water it contained, the way a still works. Also because of the heat of evaporation (latent heat) it cools the wood and causes condensation if the atmosphere is high humidity. Put some alcohol on your hand, let it dry and you will feel the heat being extracted and causing cooling. If water was in the alcohol it would not be a good solvent for shellac. Wet alcohol causes shellac to salt out leaving the solution cloudy white.
Acetone is a better solvent for oils but will also dissolve most plastics including CA. Acetone doesn't appear to cause the same degree of moisture problems because of it's lower boiling point and lower latent heat requirements. In other words it evaporates quicker and doesn't chill the workpiece as much causing less condensation. Acetone also dissolves water so it can also become contaminated. Interesting, acetone will not dissolve shellac. DNA is the solvent of choice for shellac and waxes.
Hope this doesn't confuse the issue more and cause eye glazing.