# DNA vs ACETONE



## dhallnc (Jan 2, 2011)

What is the use of each as wood turning goes?


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## ldb2000 (Jan 2, 2011)

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 .


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## Rick_G (Jan 2, 2011)

Acetone is good to get that blank you glued to your finger off.  Also if you drop your CA coated bushings into a jar of it the CA will be dissolved.   

DNA I use mainly to wipe down oily blanks before applying CA.  Dissolves the surface oil so the CA will stick a little better.  Also dissolve shellac flakes in DNA when I want to use shellac as a finish.  (Not for pens)


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## dhallnc (Jan 2, 2011)

ldb2000 said:


> 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 .



Well guess what I've been using to clean the blanks after sanding

I'll add acetone to my Walmart list.


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## Gofer (Jan 2, 2011)

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


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## dhallnc (Jan 2, 2011)

Gofer said:


> 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.
> 
> ...


 Thanks, I do want to make some of my own pen blanks from trees on our land. I'll try that.


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## ldb2000 (Jan 2, 2011)

Gofer said:


> 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.
> 
> ...


 
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 .


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## dhallnc (Jan 2, 2011)

Thanks. Learning a little everyday.


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## Larry in Harrow (Jan 2, 2011)

ldb2000 said:


> 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.


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## ldb2000 (Jan 2, 2011)

Larry in Harrow said:


> ldb2000 said:
> 
> 
> > 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 .
> ...


 
Well to avoid everyones eyes from glazing over or confuse the issue any more then it already is I will go into the details of how the DNA dries the wood but only just enough to set the record straight . 
Alcohol as I stated is "Hygroscopic" as such it absorbs water into solution . Any Alcohol whether it be Ethanol , Methanol , Isopropyl alcohol or any one of several other chemicals with an Alcohol base has this same property . This is why they are used as "Fuel Driers" (Dry Gas) , they absorb water and hold it in solution so that it can be burnt in the engine . All Alcohols have a certain amount of water in solution straight out of the can , from as little as 5% in a new can of DNA to 30% in a bottle of Isopropyl alcohol . These amounts rapidly increase as soon as the container is opened .
As for how a still works , the fermented mash is heated and since the alcohol has a lower boiling point then water the Alcohol boils out of the fermented water/alcohol solution and is then cooled in the condenser
coil and then collected .
When it comes to the drying of wood , the Alcohol soaks into the wood where it absorbs the water in the cells of the wood displacing most of the water , but not all , then being heavier then the Alcohol the water settles out of solution leaving mostly Alcohol in the cells . When you remove the wood from the soak pot the Alcohol evaporates from the wood leaving very little water behind . 
As I'm sure that EVERYONES eyes are glazed over now so I suggest that anyone who wants more information , just google "drying wood with alcohol" there is allot of info out there .


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## Larry in Harrow (Jan 2, 2011)

Sorry to butt in Butch.  Won't happen again.:biggrin:


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## Larry in Harrow (Jan 3, 2011)

The original post concerned the use of solvents DNA versus acetone.* The difference is between the evaporation rate and soluability of the two materials.
Acetone evaporates much faster, too fast for applying finishes or dyes and stains.* However it readily disolves oils and many plastics, including CA.* Therefore it is good for wiping down oily woods in preparation for finishing and for cleaning gear contaminated with CA.
Denatured alcohol evaporates more slowly making the even application of dyes and finish possible.* Non grain raising dyes disolved in DNA do not raise grain as water based products would.* DNA is the solvent of choice for shellac.* DNA will also disolve most waxes and can be used as a wipe to remove wax contamination.
Neither of the two is particularly good at removing moisture from wet wood.* The principle of soaking green wood in DNA mostly ignores the number one rule in woodworking: "Wood Moves".
Sure the alcohol may penetrate to the core of the piece and disolve the moisture but the wood has simply "moved" to accommodate the extra volume.* When you remove the wood from the alcohol it will be saturated with the alcohol/water solution some of which may run off.* The core will remain saturated until the alcohol evaporates leaving it's load of water behind.* The wood will shrink back to it's previous size and very little is gained as far as drying is concerned.
Hope this answers the original question. 
When I need to clean a wood barrel before finishing with CA I use accelerator, a better choice as Butch says.


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## Wildman (Jan 3, 2011)

Acetone and DNA have a place in your shop.  Both are great solvents for different applications. Depending upon the application lacquer thinner and mineral spirits do a good job too!

For gluing and finishing oily/resinous woods acetone has the advantage over DNA. For cleaning up CA glue acetone has the advantage over DNA.  Some people prefer to use lacquer thinner on resinous woods.

DNA is great for sanding because it does not raise the grain. Also for cleaning bushing and sanding dust on wood. I use DNA to clean acrylic blanks or look for scratches, would never use acetone. If you want a high sheen finish on wood DNA is preferable to mineral spirits. I have not found that to be true. 

I did use mineral spirits to sand and remove sanding dust on some projects. Find myself using DNA more because it evaporates and easier to remove with less fumes. 

I still use water to final sand and polish a finish on wood and acrylics.


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