Alcohol Soaking

Presentation at SWAT

2007-05-25T11:44:00.000-07:00

I will be a demonstrator at SouthWest Association of Turners(SWAT) symposium October 5-7, 2007 in Wichita Falls, Texas. The presentation will be on drying turned pieces using the alcohol drying protocol I developed.

At the present time there are two sessions scheduled.

Key points

• Development of the alcohol drying protocol
• Methanol and ethanol health and safety
• Understanding Material Safety Data Sheets (MSDS)
• Alcohol drying protocol
• Determining alcohol concentration in a solution
• Removing water from used soaking solution

Attendees will learn

• Alcohol soaking protocol theory
• Difference between methanol and ethanol health threat
• How to process a roughed turned bowl
• Determining when a roughed turned bowl is dry
• What a MSDS is for and how to decipher it
• How to determine alcohol concentration

See you at SWAT.

Vine Maple Goblet

2006-11-29T09:00:00.000-08:00

On Wood Central’s Turning Forum Steven Lewis asked about turning goblets from green wood. I decided to give it a try using the alcohol drying method. The only green wood readily available to me is vine maple.

The limb was about 2 ½" in diameter. As you can see the limb was not straight so I expected the stem would warp when drying.

Bowl thickness is about 3/8"

The roughed out goblet is about 2" in diameter and 6" long. and the stem is ½" in diameter.

The piece soaked over night for my convenience. An hour or two in the alcohol would have probably been sufficient. After removing from the soaking container the goblet is wrapped in paper leaving the bowl uncovered.

The goblet is weighed.

Placed upside down on a rack for drying.

Weight in Grams.
11/20 - 1000 - 143
11/21 - 0830 - 117
11/22 - 0700 - 110
11/24 - 2130 - 106
11/25 - 1230 - 106
11/25 - 2100 - 105
11/26 - 1300 - 106
11/27 - 1100 - 105

At 10:00AM November 20th the goblet weighed 143g. Four and a half days later it weighed 106g. By the 27h it hadn’t lost anymore weight so I finished turned the goblet.

The bowl did not distort very much.

Since the pith was in the stem I figured the stem would warp and I was not wrong.

With the tool rest set at the center line I adjusted the goblet to have the stem centered.

Bottom and stem are rounded.

After further refinement of the stem the pith is revealed.

Tenon is glued into a waste block mounted in the chuck.

Steady rest provided stability for finishing the inside.

Goblet is stabilized with a wooden plug on the live center.

Unfinished goblet stands straight and tall.

After two days and two coats of Rocklers Gel Polyurethane the goblet stem remains straight.

Yew box.

2006-11-29T08:39:00.000-08:00

This yew wood came from a tree that had died during the previous summer. Recently cut down the wood was wet but not as wet as a live tree freshly cut. Other turners got to the tree first so I am left with smaller limbs to work with. A box was hollowed from a limb section.

The top portion roughed out to 1/4" wall thickness. The inside is rounded to a center thickness of approximately 3/8. The bottom portion roughed out to 5/16" thickness. The inside rounded to a center thickness of approximately ½".

The pieces soaked in alcohol overnight for my convenience. An hour or two in the alcohol would have probably been sufficient.

After removing from the container the two pieces were butted end to end with the box interior exposed on each end.

This procedure for wrapping boxes was instigated by Ron Sardo, or was it Phil Duffy, shortly after I published the alcohol drying procedure in November of 2004.

Wraped and on the drying rack.

11/20 - 1000 - 126
11/21 - 0830 - 111
11/22 - 0700 - 109
11/24 - 2130 - 108
11/25 - 1230 - 108
11/25 - 2100 - 108
11/26 - 1300 - 108

At 10:00AM November 20th the box weighed 126g. Four and a half days later it weighed 108g. By the 26h it hadn’t lost anymore weight so I finished turned the box.

No degradation and very little warping.

In retrospect I should have turned the sap wood away when rough turning to reveal the rich colored heartwood. I will do that with the next box I turn from a yew limb..

Determining Alcohol Percentage

2006-11-23T20:05:00.000-08:00

Calculating alcohol concentration by weight.

The phenomenon of miscibility is key to drying wood by alcohol soaking. Miscible liquids will reach a uniform concentration when combined in a container. An example is a bottle of wine which maintains a uniform consistency of alcohol and water no matter how long it sets undisturbed.

When a piece of wood is placed in an alcohol solution the phenomenon of miscibility will cause the water in the wood and the alcohol in the solution to migrate until they reach equilibrium. The final alcohol concentration in the wood will always be less than the starting alcohol concentration of the soaking solution.

Replacing water in wood with alcohol is the key mechanism for drying wood faster. Alcohol readily moves through cell walls and has a lower vapor pressure than water. As the concentration of alcohol in the wood goes down the drying time increases. Therefore, it is useful to know the alcohol concentration of the soaking solution.

A hydrometer is one way to measure alcohol concentration. To be more accurate the temperature of the solution needs to be measured to correct for density changes due to temperature. The easiest way to measure temperature is to use a hydrometer with an integrated thermometer. Hydrometers are expensive and breakable. Since a scale is needed to track the drying of wood pieces a method of determining alcohol concentration by weight would utilize existing equipment and minimize cost.

Knowing that alcohol and water have different densities I concluded that the alcohol concentration of a solution could be calculated by a ratio of weights. I contacted Professor Shawn Bearden in Pocatello, ID and ask him if he could help me devise a procedure. Shawn developed the graph and table used in this procedure.

The procedure requires the following:

A scale capable of measuring a minimum of 1 gram(g) increments.

A see through container with a narrow neck to increase the accuracy of the sample size to be weighed.

A copy of the Alcohol Percentage Graph and Table.

This water bottle has a color change near
the top which is used for the measuring line.

1. Select a narrow neck vessel for weighing the samples. I prefer to use plastic since I am sure I will drop it sooner or later. A salad dressing bottle or water bottle make good sample vessels.

2. Draw a line about an inch below the top of the sample container. The line needs to be narrow enough to accurately measure each sample.

3. Weigh the empty container and record the weight.

4. Fill the container to the line with water.

5. Weigh the sample and record the weigh.

6. Empty the container and fill it with soaking solution to the measuring line.

7. Weigh the sample and record the weight.

Calculating the weight ratio.

The ratio is calculated by dividing weight of the water by weight of the solution. To be more accurate subtract the weight of the empty bottle from water and solution weights.

(Weight of water) - (weight of bottle) /(Weight of solution) - (weight of bottle)

Example calculation:

Empty bottle weight equals 23g.

Water sample weight equals 632g.

Solution sample weight equals 550g.

632g - 23g /550g - 23g

609g /527g = 1.155597

The resulting quotient is the ratio and will be a number greater than 1.

Rounded to 4 dismal places, ratio = 1.1556

Converting the quotient to percentage of alcohol concentration.

Using the graph find the ratio on the horizontal or X axis. Read the alcohol concentration on the vertical or Y axis.

Using the table find the ratio and the corresponding alcohol concentration.

After calculating the ratio round the number to 4 dismal places. The first two decimals correspond to the numbers on the chart and graph. The third and forth decimals are used to interpolate the concentration between the values given.

The first 3 numbers of the example ratio 1.15 correspond to the number on the chart for 62.20% alcohol concentration. The next higher ratio is 1.16 which corresponds to 65.79% alcohol concentration.

The last two numbers are used to interpolate between the ratios 1.15 and 1.16. Treat the last two numbers as a percentage of the value between 62.2 and 65.79. In the example the last two numbers become 56% (0.56) of the difference between 65.79 and 62.20.

65.79 - 62.20 = 3.59

3.59 x .56 = 2.01

62.2 + 2.01 = 64.21

Add the difference to the lower number which yields the alcohol concentration.

For alcohol soaking purpose it is not necessary to do the math to determine an exact percentage of alcohol concentration. A ballpark number is good enough.

Experience has shown that higher concentrations of alcohol in the soaking solution will produce the best results of faster drying times with less degradation of the piece. Therefore it is recommended that the starting alcohol concentration be greater than 60%.

Wood can be successfully dried with lower concentrations but the advantages of soaking in alcohol are diminished. Drying time will increase. Because there is more water in the wood, which does not migrate out of the wood as easily as alcohol, more stress will develop across the walls of a piece which increases the probability of cracking.

It is only necessary to weigh the water once as long as the same bottle is used for weighing the solution sample. The water weight for the bottle used in the example will always be 609g. For subsequent test it will only be necessary to weigh a solution sample.

After weighing the solution rinse out the bottle with a small amount of alcohol and add it to the solution container. Compressed air blown into the inverted bottle will insure it is dry.

Alcohol Percentage Graph and Table is available in PDF format. Print a copy of the chart for your convenience.

Order your shirts before they are gone.

2006-11-04T18:26:00.000-08:00

There are only a few alcohol soaking shirts left. At the present I do not plan to order more shirts unless there are a large number of requests. The shirts are $14.95 plus $4.50 shipping and handling to United States addresses. You can order the shirts here.

As of Saturday evening November 4th the remaining number of shirts:

Time is Fine
6 - Large
2 - Medium

Don't Turn
1 - Extra Large
4 - Large
3 - Medium

Shirt sales have been the main source of financial support to offset the cost of testing and perfecting the alcohol drying protocol. I continue to refine the process and disseminate information as time permits. Thanks to all the people who purchased shirts and supported my efforts.

Several people have suggested I produce a video on the alcohol drying process. At this time I have not been convinced that sales of a video would yield enough return to justify the cost. Please take the time to email me your thoughs on the issue.

Silktree Closed Form

2006-06-10T22:19:00.000-07:00

I started turning this piece about 2 weeks ago. I had it roughed out and just started to hollow it when I had to set it aside. Put it into a paper bag packed in wet shavings. The log was cut last November and sat outside with the ends sealed until the end of May. The pith is not sound but I wanted to turn a whole log hollow form to show off the grain.

I applied super glue to the cracks around the pith before packing the partially turned piece in shavings.

When I put the roughed out piece into the alcohol there was no further cracking. I have successfully dried pieces with the pith in the sides using the alcohol soaking protocol. This is my first attempt with silktree.
I did not check the concentration of alcohol before putting the piece in the bucket. If the ending alcohol percentage is above 70% then I expect the piece to be dry in 5 to 7 days. Silktree is quite porous which allows it to lose moisture quickly.

Fresh out of the alcohol.

After drying for one hour the piece was wrapped, weighed, and put on a rack.

Even though the ending solution is below 70% I expect the piece to be dry in 5 to 7 days.

Silktree from Gresham. OR. Cut down 11 November 2005.
Diameter: 7.5"
Height: 7.5" including tenon
Wall thickness: 0.5"
Rim opening: 2.5"
Bowl into alcohol solution: 2145, 06/10/2006
Bowl out of soaking solution:
Alcohol percentage of solution:
Begin soak: Did not measure.
End soak: 65.5% *

Weight in grams
06/11 - 1100 - 1286
06/11 - 2145 - 1184
06/12 - 0905 - 1112
06/12 - 2115 - 1070
06/13 - 0815 - 1034
06/13 - 2130 - 1002
06/14 - 0930 - 979
06/14 - 2300 - 956
06/15 - 1330 - 937
06/16 - 1245 - 907
06/17 - 0715 - 883
06/18 - 0915 - 857
06/19 - 1400 - 840
06/20 - 1330 - 828
06/21 - 2015 - 812
06/22 - 1400 - 807
6/23 - 2200 - 795
6/24 - 1400 - 794
6/25 - 1530 - 793
6/26 - 1500 - 791
6/27 - 2000 - 790
6/28 - 1500 - 788
6/29 - 1530 - 790
7/16 - 1000 - 789

Silktree
Click on picture to enlarge
* - I have had success soaking bowls in solutions as low as 50% but after further research I don't recommend it. I will add dry alcohol to the solution to bring it to a concentration greater than 70%.

06/24/2006 - Looks as if I missed the drying time on this piece. A combination of low alcohol concentration and the small opening probably lead to the slower drying time. Still, 13 days to dry a closed form is not bad. The piece will probably not lose any significant weight from now on. I will continue to record data for a few more days then unwrap it. There are no indications of degradationon the inside and the pith is intact. Final pictures in a few days.

07/16/2006 - Unwrapped and started to finish the hollow form. Final weight take today is 789 grams. No change in over 2 weeks. Since the 24th of June when I called the piece dry enough for turning it lost a total of 5 grams which represents 1% of the total weight loss.

Data Cards

Bottom has very little distortion.

No degradation of the CA glue I applied to the cracks developing around the pith during rough out.

Top nearly flat with very little distortion of opening.

The final measurements at the widest diameter are 7 7/16" by 7 1/4". The piece remounted tightly in the chuck which indicates how little the foot distorted while drying.

Very little material was removed to reture the top opening and the bottom tenon.

After turning and power sanding to 150 the piece is ready for a coat of finish.

Since silktree is porous and soft. I apply a coat of finish before making any decorative cuts like rings I intend to turn around the opening. The CA glue has been turned away from one pith but is still visible in the other. The crack on the inside is barely visible so I could turn away more material to reduce the crack size visible on the outside.

At this point I haven't decided if I want to add a collar.

Finish brings out the contrast in the different layers of wood.
The finished piece is available for purchase in the Gift Shop at Wood n Heart.

Finished pictures added 12/22/06.

White Oak Bowl Drying Process

2006-06-08T08:55:00.000-07:00

I turned this bowl from a tree I obtained the beginning of May 2006. About 11 1/4" in diameter.

Click on pictures to enlarge.

I turn bowls close to the pith as can be seen here. I have found that even if the pith area cracks it is going to be turned away when returing the rim. Even if I trimmed an inch from the pith when roughing out the blank, as most people suggest, the end grain edge will deform upward requiring further reduction in bowl height. I seldom ever have to trim the walls lower because of cracks extending from the pith.

The wall thickness is 3/4" and the rim is about 1" thick. The rule of thumb is to rough bowls to 10% of the diameter. Following that rule I would have turned the walls to 1 1/8". The rim is thicker because I plan to form a bead on the outside of the bowl to facilitate lifting it with one hand.

The bowl was placed in a 13 quart stainless steel bowl. No problem with green white oak it goes right to the bottom.

The cover I use is made by placing a heavy piece of plastic sheeting over the bowl then wrapping the rim with plastic shipping tape. By stretching the tape a reasonably tight fit is achieved. This is only the second cover I have made in five years.

After soaking about 20 hours the bowls was removed. The bowl could have been removed sooner but the longer soak time suited my schedule.

After allowing to dry for about one half hour it was ready for wrapping in a brown paper grocery bag.

After cutting the paper roughly to size it is helpful to tape down two sides to keep the paper in place while taping.

Gather the paper as you wrap tape around the rim.

Trim the paper to the in side edge of the rim.

Weigh the wrapped bowl and place it upside down on a rack to allow air to circulate inside the bowl.

A data card is not necessary but at least write the date, time , and initial weight on the paper. This will allow you to estimate when to start checking the bowl weight if you want to turn it as soon as possible. Most bowls are dry in about 2 weeks. I expect this white oak bowl to stop losing weight in 8 to 10 days.

My intent was to post this information the day the bowl was wrapped and set aside to dry. Then post the weight each day so turners could follow the progress. Life sometimes gets in the way of good intentions.

White oak from Red Lion Motel, Kelso, WA. Cut down 1 May 2006.
Diameter: 11.25"
Height: 3"
Wall thickness: 0.75"
Rim thickness: 1"
Recess cut in bottom for expanding grip with chuck jaws: 0.25" deep, 3.25" diameter
Bowl into alcohol solution: 1515, 06/01/2006
Bowl out of soaking solution: 1030, 06/02/2006
Alcohol percentage of solution:
Begin soak: 75.3%
End soak: 73.1%

Weight in grams.
06/02 - 1115 - 1490
06/03 - 0040 - 1366
06/03 - 0625 - 1324
06/03 - 1520 - 1250
06/04 - 1045 - 1198
06/04 - 2025 - 1176
06/05 - 0840 - 1144
06/06 - 0055 - 1112
06/06 - 0835 - 1106
06/06 - 2150 - 1082
06/07 - 0800 - 1072
06/07 - 2000 - 1058
06/08 - 0830 - 1048
06/08 - 2015 - 1038
06/09 - 0740 - 1026
06/09 - 2010 - 1016

Click on picture to enlarge.

The paper is very loose and the pith is hanging in there.

Picture taken 06/09/2030.

06/10 - 1015 - 1012
06/10 - 2145 - 1008
06/11 - 0905 - 1006
06/11 - 2145 - 1000
06/12 - 0905 - 997
06/12 - 2115 - 998
06/13 - 0815 - 995
06/13 - 2130 - 992
06/14 - 0930 - 991
06/14 - 2300 - 992
06/15 - 1330 - 991
06/16 - 1245 - 991
06/17 - 0715 - 989
06/18 - 0915 - 986
06/19 - 1400 - 985

White Oak bowl drying curve.
Click on the chart to enlarge.

The charted weight and time data yields a curve which is typical of an alcohol soaked piece. At this point the bowl weight will fluctuate with the shop humidity. I consider the piece dry and ready for turning. I will continue to record data for several days and up date the chart in a few days.

06/17/2006 - After 2 weeks the bowl weight is changing in relation to shop humidity. .

06/21/2006 - Removed the paper yesterday and took several pictures of the white oak bowl. There were three small cracks on one end of the bowl that do not go all the way through. My experience has been that the cracks will turn away.

The paper became very loose as the wood shrank.

Recess ovaled to 3 9/16" x 3 13/16"

Narrowest outside diameter is 10 5/8"

Widest outside diameter is 11 1/8"

Pith raised about 1/4"

Bottom distortion is less than 1/8"

Three small cracks on the outside wall of one end

My experience is that the cracks will be turned away.

Alcohol Bowl Drying on David Marks Website

2006-04-20T08:15:00.000-07:00

Dick Parr hosted David Marks at his home after a demonstration to the local turning club in 2005. Dick explained the alcohol drying process while showing his turnings to David. David used the procedure on a large redwood burl piece he needed to complete in a limited time frame. The piece was successfully dried, completed, and delivered on time. David has subsequently added the alcohol drying process to his Alternative Ways To Dry Wood Turnings
on his web site.

Alcohol Brands and Sources

2006-03-10T16:20:00.000-08:00

My recommendation is to use denatured alcohol that has a low percentage of methanol. I have identified several brands that meet this criteria. When possible I have consulted a Material Safety Data Sheet(MSDS) to confirm the contents and relative concentration. I will add to this list as information become available. If you know of a product that is not listed here please notify me. Alcohol sold as denatured can be any where from 100% methanol to less than 5%. Ethanol percentage can be from 0% to 95%. Most ethanol is denatured by addition one or more of the following: methanol, methyl isobutyl ketone, ethyl acetate, and gasoline. Ethanol is the least harmful of the ingredients so it is logical to use a substance that is highest in ethanol and lowest in other ingredients.

True Value Hardware brand denatured alcohol.
UPC for one gallon can is 42909 04814.
Listed ingredients on can:
Ethyl Alcohol
Methanol <4%
Methyl Isobutyl Ketone
Ethyl Acetate

Parks, division of Zinsser Co., denatured alcohol
Listed ingredients in MSDS dated: 08/09/02
Ethyl Alcohol: 87-92%
Methanol: 5-10%
Methyl Isobutyl Ketone: 1-5%
Ethyl Acetate: 1-5%
Rubber Solvent: 1-5%

Sunnyside brand denatured alcohol.
MSDS dated 1/25/06, Percentage by weight.
Ethyl Alcohol: 85.7%
Methanol: 3.6%
Methyl Isobutyl Ketone: 1.9%
Ethyl Acetate: 1%
Naphtha: 0.8%

Mohawk Shellac Reducer
MSDS, Percentage by weight.
Ethyl Alcohol: 81% - 90%
N-Propyl Acetate: 1% - 10%
Isobutanol: 1% - 10%
Isopropanol: 1% - 10%

It is incumbent on each individual to become familiar with the chemicals they are using and the consequences of their exposure to them. The information listed here is for information only and is not deemed to be a substitute for a Material Safety Data Sheet(MSDS) that each manufacture is required by United States law to provide fee of charge to any user. Unfortunately not all manufactures have easy on line access to their products MSDS. My opinion is that all MSDS should be required to be available on line without any incumbrance for quick and easy access.

Here are a couple links to locate stores that carry denatured ethanol.

Sunnyside
http://www.sunnysidecorp.com/whereto.htm

True Value Hardware
http://www.truevaluecompany.com/storelocator/

Mohawk
Distributor Lookup

Turner feedback on alcohol soaking

2005-12-11T14:46:00.000-08:00

The following is some of the feedback I have received from turners that have tried using the alcohol drying process. I will add more responses as time permits.

I had to start the post with my favorite feedback message because of this one sentence, "I have been using the paper bag and wet chip system for some time and last week took 2 cherry bowls out to check them and threw them in the burn pile." That pretty much sums it up for me.

Email 12/14/2005

Dave I have started using the alcohol soak. I have about 6 bowls wrapped now and finished one cherry bowl. 14" and 2 1/2 deep. Soaked it for 3 hours and set aside for a couple of weeks. Last night I unwrapped it and was surprised it did not look like a potato chip. I have been using the paper bag and wet chip system for some time and last week took 2 cherry bowls out to check them and threw them in the burn pile.

The one I soaked had no cracks and did not warp much at all. I had no trouble retruing the bowl what so ever. I have a oak burl and 4 walnut bowls drying now.

Will keep testing and let you know. As of now I love the system.

Dick Hines

Email 3/27/05

Alcohol Bowl Drying Results
Kevin Gerstenecker

Dave, here are my results of my experience in drying green, rough turned bowls using your method involving Denatured Alcohol. To say I have been impressed with the success of this method would be an understatement. Listed below are the techniques I have found that have provided excellent results for me.

To date, I have roughed and dried, from green turning stock approximately 45 bowls. (There may be a couple that snuck by me when keeping track of my progress.) ;-)

Species: Using the Alcohol Drying Method, I have dried the following with excellent results:
Apple - Both Crabapple and Fruiting Tree Wood
Ash - Green Ash, White Ash
Beech
Box Elder
Bradford Pear
Cherry - Black Cherry and Pin Cherry
Cedar - Eastern Red Cedar
Dogwood - 1 small piece
Elm - Chinese, Red
Hawthorn - Washington, Cockspur
Maple - Silver, Norway, Red
Osage Orange
Sycamore
Walnut - Black

Problem Species: The only problems I have experienced using the Alcohol Drying Method have been with Ash and Walnut. I have roughed, soaked and dried about 8 Ash Bowls, and I have had some cracking in the end grain area of each bowl. To date, only one has been severe enough to not be able to turn the cracks away during the finish turn. Most of the cracking is light, and shallow. I have different wall thickness on my rough turned bowls, but it seems to make little different. All of the Ash Bowls have been above 6" in size. I have one Natural Edge Ash Bowl drying that showed cracking within 8 hours of removal from the Alcohol. One Walnut Bowl has some end grain cracks as well, but I have hopes they will turn away during the finish turning process.

Wall thickness: I think it is very important in the success of this drying process to pay attention to wall thickness of your rough turned items. On bowls up to 6" in diameter, I try to maintain a 3/8" to 1/2" wall thickness on the rough turned bowl. I have found on some species, where movement is limited, that is not necessary, and on other species, like Apple, it is essential to have good thickness due to the severe movement of that species.
On larger bowl, of which I have used the Alcohol Drying Method on bowls up to 15" in diameter, I try to maintain a wall thickness of 5/8" up to 1", depending on the species. (As a side note to the Ash bowl cracking problems, those were all larger bowls, in excess of 6", and had thick walls, at least 3/4 or more. I think wall thickness, in this case too thick, is a direct contributor to the cracking I have experienced. Others I have talked with have dried Ash with no problems.)

My Process: Here is the process I use drying my green, rough turned bowls using a Denatured Alcohol Soak.

My blanks are cut round on the Band saw, and turned right away. I rough turn the bowls, and either blow them clean with air, or brush away any dust and shavings, to help keep the Alcohol debris-free.

I submerge the rough turned bowl in Alcohol immediately after they are rough turned. If they tend to float, I use scraps of Corian placed in the bowl to hold them under the Alcohol. I soak the bowls standing upright, as they would be when finished.

I soak all of my rough turned, green bowls a minimum of 24 hours. This is mostly due to convienience for me. If I turn a bowl on a weekday evening, I soak it, and remove it the next evening after work. On the weekend, I just remove it the next day, but it is more times than not a 24 hour soak. My results have been so good, I will continue this timeline.

Upon removal of the bowls from the Alcohol, I wipe the exterior surface lightly with a paper towel, or shop rag. I wrap my bowls immediately using brown grocery bag paper, and I secure the paper with one wrap of masking tape around the exterior of the bowl, near the rim. I always make sure the paper is folded tightly over the rim in into the inside of the bowl about 1/2" to 1" or so. I trim away any excess paper inside the bowl that could impede proper air circulation.

I dry my bowls on a plastic shelving unit that has grate-like shelves with large openings. The bowls are dried bottoms up, with the interior facing down, like Dave suggests. I also write the date on the masking tape on each bowl, so I know when it was removed from the Alcohol for drying. I have finish turned small bowls in as soon as 6 days of drying, but I now wait at least 2 weeks, and I have been unwrapping the bowls after 14 days and letting them air dry "naked", facing down, for another week, or when I can get to them. I find no problem doing it this way, as the bowls are dry enough after 2 weeks to be problem free. Another thing I think contributes to the success I have had using Dave Smith's Alcohol method is the environment where I dry my bowls. I have a basement shop, and I feel that the conditions in my basement are perfect for drying these Alcohol soaked bowls. It stays cool, without a lot of air circulation directly on the bowls. The humidity is constant, but not really high, as I use a dehumidifier. The humidity is still a bit high though, as it is in most basements. With a dedicated shop in the plans, I will still be drying my Alcohol soaked bowl in my basement, as I think the environment there is ideal for the task.

In summary, I have had what I consider excellent results in drying rough turned, green wood using this method. Some of the wood I have used this on was turned as soon as 1 day after being harvested, and without saying, it was VERY wet. Literally "dripping wet" in some instances. I have had very little movement in the finished bowls I have turned using Dave's method. The bowls that did exhibit some movement were turned before a minimum 2 week drying period. Some of the historically "difficult" woods to dry, Sycamore and Apple come to mind, have been the most problem free for me. On the bowls that I have allowed 2 weeks or more for drying before the finish turn, have had no movement, or movement that is hardly discernable.

Dave Smith should be highly commended for bringing this technique to the turners of the world. It is very effective, and I will not turn green wood without an Alcohol Bath waiting. This method helped me fill last years Christmas Bowl Orders before the holiday deadline, of which would have never been possible otherwise. This has brought much joy and satisfaction to my "turning affliction", and I am forever grateful for the foresight and work Dave has put into this technique. I am even more grateful for Dave's visit last October when he told me about this process. I have been using this method since, and I will use it as long as I am turning. Good Lord willing, that will be a long time!

Thanks Dave!!!!!!, you have made a pleasurable experience just that much more enjoyable. For that, I offer my heartfelt thanks!

Email 4/29/2005

Dave,

I tried other suggestions for drying such as dishwashing detergent, and boiling. I did not have a lot of success with these methods so I went back to coating my bowls with Anchorseal and setting them aside to dry for a long time span. When I heard about your new method I decided to try it because of the reliable turners that had used it for a year, and recommended it. I have had remarkable success with it, recommended it to fellow turners, and as you know I let turners know about it on the web. I appreciate your work in developing the method of using DNA, and letting us know about it, and I am impressed you did all of this with no profit comming to you. Thanks Dave, from South Georgia. If you are ever in this neck of the woods stop by and visit.

Glenn Hodges
Nashville, Ga

Email 10/17/2005
Ultimate alky test

Hey Dave.

I've been using your alcohol soaking protocol for several months with great success. When I came across a Pear downed by hurricane Katrina, I snatched it up. It had a cluster of 2 crotches side by side that I just had to try a hollow form from the entire cluster. I'm not sure if you remember me posting it on SMC and the WOW sites. To me, it was the ultimate test for the alky soak, and it worked like a charm! The turning has a total of 6 piths around the circumference, every single one came through perfectly intact. I was discussing it with Jim Ketron in chat, and told him it could be the poster child for alcohol soaking. I just wanted to drop you a line of Thanks again, for bringing this out.

Sure, you have my permission to put it on your site, that would be great. The finished size ended up at 10.5" in diameter x 5.5" tall, with wall thickness just over 1/4". I had roughed turned the walls between 1/2" and 5/8". It was soaked about 24 hrs. If I'm not mistaken, it was a total of 17 days from the time I wrapped it until I took the finished pics.

Travis Stinson

Email 3/19/2006

Hello,

My name is Jeff, I am from Massachusetts, I found your site about a year ago. You know looking for a way to dry wood faster and effectively, ethanol alcohol works very well. I've done big bowsl to vessels, big and small. I just wanna say Thank You!!! for putting up such useful information! I could not find ethanol any where that had it in 95% or better. I had to go on line and order it $135.00 for 5 gal. The only problem wood I had was modrone burl from OU, but that was do to human error not the ethanol.

Thank You again,

Jeff

*Note to the reader.*

Read the Alcohol Source article for info to locate a source for denatured alcohol with a high ethanol content. Do It Best has Sunnyside denatured alcohol in 5 gallon containers for $41.49. Some affiliates will take free delivery of on line orders.

Posted 5/28/2006 on Woodturner's Rescource Woodturning Forums

For the last month I have been using the DNA method for drying and wanted to pass along the results.

Quantity 11 bowls rough turned 1" thick for every 12
" in diamiter. Placed in bucket of DNA overnight, then one hour drying on rack, then bottoms covered in craft paper placed upside down for 2 weeks.

Wood used Maple, Birch, Chestnut, Mohagany.

Results: on all pieces noticed less wood movement, all dry after 2 weeks, one piece of birch cracked alittle, but not sure if the crack was already there or not.

This is my new preferred method and will use this now on for green turnings. I get quite a bit of free green wood and now always have dry rough turnings to finish is great.

Just a little info to pass on.

Larry
Yakima, WA.

Posted on penturners.org

6/1/2006
I read your article over at WoodCentral 'bout a year ago on using DNA, experimented around with it, and have used it countless times since. I also introduced it to a number of our club members in a Saturday demo I did on drying wood. Even had a chemist friend at the demo (when mentioning 'bonding water and alcohol I needed someone much smarter than me :)

Your process has worked amazingly well for me.

Sorry, didn't mean to ramble on in the ad area (did I mention I am totally impressed with your process/work :)

6/2/2006
And you are more than welcome to add my post to your blog.

I would add pictures but the bowls I have completed have (happily) been sold
Woods used have mostly been spalted beech, walnut,cedar, pecan, cherry, mulberry,poplar, and holly.

John P
Chesapeake, VA

Posted on Wood Central Turning forum
Friday, 20 October 2006, at 3:08 p.m.

Here's a photo of a Ambrosia Maple bowl I just finished. Watco finish but still needs to be buffed. 12" by 3.5". This was alcohol dried and was a log 3 weeks ago. Thanks for looking and all comments and critiques welcome.

Tony

Posted on Wood Central Turning forum
Saturday, 21 October 2006, at 2:23 p.m.

Sycamore bowl measures 14.5" by 3.5" Wall thickness is a heavy 1/8". Bowl weighs 13 ounces. This is another alcohol dried piece. Sycamore responds well to this method of drying. Watco finish. I think on the next one I'm going to try bleaching the wood. Does Sycamore bleach well? As usual all comments and critques are welcome.

Tony

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Alcohol Soaking Q and A

2005-12-05T23:41:00.000-08:00

I have answered many questions since publishing the alcohol drying process in November 2004. My intent here is to compile a collection Q & A to make it easier for people to understand the process.

The following 4 questions were asked by Greg in an email dated 12/04/2005

Q: Does the alcohol itself take on water as the bowl takes on alcohol? Meaning do they exchange liquids?
A: Yes, water and alcohol are miscible. The water in the wood and the alcohol in the container will exchange until they are at equilibrium.

Q: Does alcohol retard mold, staining etc.?
A: Alcohol in high enough concentration will kill most organisms. The same process that causes alcohol to achieve equilibrium with water in wood will essentially dehydrate an organism which isn't good for it. Once the alcohol evaporates new organisms can colonize the surface of the wood. Some people speculate that natural mold inhibitors in wood are destroyed by soaking in alcohol or boiling. This is not something I am inclined to delve into since the alcohol process drys pieces in a short time making the wood too dry for most organisms to flourish.

Q: Does the alcohol lose strength with use?
A: Yes, alcohol concentration in the soaking solution will decrease over time. In my initial testing I used fairly small pieces in a small container. I added alcohol as the level in the container decreased which kept the concentration from drooping too low. I have done some tracking of alcohol concentration recently to identify a lower limit in which the process is effective. I hope to have more on that soon.

Q: I currently boil per Steve Russel's method. ...Would you recommend alcohol soaking over boiling? It would be much easier to throw bowls in a large container rather than boiling.
A: I am familiar with Steve Russel's method. Steve has done a lot of work developing the boiling process and has freely shared his information with the turning world. I used boiling for a while but it is inconvenient especially if you are only doing an occasional turning. Also, boiling does not speed the drying process. One of my goals was to devise a passive method for improving the bowl drying process. Just drop the piece in a bucket of alcohol and take it out the next day or next week if you want. I haven’t boiled a bowl in over three years so you can conclude that I recommend alcohol soaking over boiling.

A few more questions from Greg in an email dated 12/08/2005

Q: With the alcohol soak method is the tendency of the wood to distort diminished, if so, how much?
A: Bowls do not distort as much when soaked in alcohol before drying. It is counter intuitive to think thinner walls result in less distortion. I found it to be true when I started testing the process.

Q: Do I ignore the 10%wall thickness rule?
A: I don't use the 10% rule with alcohol soaking. When I started the testing process instead of starting with the 10% rule of thumb I started at 1/2" which I thought was extremely thin. It turns out that 1/2" is usually a good thickness for up to 8" bowls. I usually turn small bowls to 3/8" thickness and finish turn to about 1/4". There are a lot of factors in bowl distortion so my wall thickness recommendation are just an other rule of thumb.

Q: Once the bowl is dry is there any odor from the booze and will polymerized tung oil be compatible as a finish?
A: Alcohol will completely vaporize and leave no odor. There will be no problem with any finish you use on the dry wood. Most people forget that shellac is thinned with denatured alcohol and once the alcohol evaporates the finish is food safe.

Richard Dowling asked this via email on 1/3/06.

Q: "I picked up some Madrone in California last week. It's very green. Do you have any experience turning it?"

A: My experience with madrona is that it needs to be turned thinner than the 10% rule. Also, use fresh alcohol and soak the roughed out bowl at least 24 hours. I had some spectacular failures when I left the walls too thick and soaked them in an old solution that had a low percentage of alcohol. Subsequent pieces that were turned thinners and soaked in fresh alcohol had very few problems.

Madrona needs to be turned soon after cutting. It splits every which way you can imagine. It needs to be sealed on all surfaces and kept out of drafts and sunlight. Madrona is also susceptible to blue stain which will develop in the sealed blanks.

Questions from Barb and Mike Hays. Email dated 2/26/06.

Please let us know about how long to soak 10 pen blanks taped together. Green maple.

The following answers assume the wood in question is straight grained with no defects.

Q: How long do we soak them?
A: Seperate the blanks before placing in alcohol. Soak them over night or about 8 hours.

Q: Then what do we do with them?
A: After removing them from the alcohol set the blanks on a rack and let the surface dry. It takes about an hour. Once the surface is relatively dry, coat the ends with an end grain sealer. Coat the sides about 1/2" from the end. Leave the rest of the blank unsealed. Place the coated blanks on a rack. It take between one to two weeks for the blanks to stabilize. I cut pen blanks from 1/2" to 1" square with lengths from 4 1/2" to 6".

An alternative to sealing the end grain after soaking in alcohol is to put the blanks in a paper bag and close the opening. This method leads to more end grain checks and extends the drying time. However, it is expedient when generating large numbers of small blanks.

We enjoyed your program at the Olympia woodturners meeting last month.

Barb and Mike Hays

Questions from Terry Bourk.
Email dated 2/26/06.

Q: Is there some reason why you don't give the composition of the DNA sold by Home Depot on your blog??

A: I have listed the brands of DNA that are mostly ethanol. Klean-Strip SLX
brand is about 45% ethanol and over 50% methanol. I also miss read the MSDS for SLX brand DNA. After someone on WoodCentral commented on the deception I took a closer look. That is when I put the info on my blog about brands that have high ethanol content.

Question from Michael Stadulis
Email dated 6/13/2006

Q: Maybe you've written this someplace, but I'm curious if you have any empirical data about how much less warpage you get this way(alcohol drying process)....?

A: When I began investigating methods for shortening the drying process I decided trying to quantify warpage was going to be very difficult. I decided the easiest way was a go, no go test. Can I turn a finished bowl from the dried piece? As you may guess nearly every piece passed the test. A while back I began measuring the maximum thickness I could turn from a dried bowl. What I do is retrue the rim of the bowl and then scribe the largest and smallest circles and measure the difference. From the small amount of data I have gathered a bowl roughed to 5/8" will yield a finished piece with wall thickness of about 7/16". I abandoned making control pieces early in the experiment because I was not writing a Masters Thesis. I just continued with what worked and used it.

Question from Suzanne
Comment dated 10/21/2010

Q: I have some fresh walnut blanks that are 3" x 3" x 11". Do you think there's any chance of drying them using your DNA method?

A: Yes, it is possible to dry the turning squares using the DNA method. Soak the squares in denatured alcohol over night. Remove and coat the ends and about 1/2" of the sides with end grain sealer or wax. Stand the pieces on end and allow to dry. Although I can't prove it helps the drying process, I flip the squares end for end each time I weigh them. Walnut is a porous wood and will dry fairly quickly.

Question from Anonymous
Comment dated 12/25/2010

Q: David, when we pull our blanks from the DNA and begin drying them...what are we removing during the drying process? Are we removing water, or has most of the water in the bowl been replaced with DNA, and we are now waiting for the DNA to migrate to the surface, to evaporate off?

A: When the bowl is submerged in alcohol water in the wood will exchange with alcohol in the solution until an equilibrium is reached. When the bowl is removed from the solution alcohol will evaporate quicker than water because of a higher vapor pressure.

Question from Dora
Comment posted 11/25/2010

Q: I design jewelry in wax, and I am interested in locating pure solvent alcohol for heating the instruments I use. I have not had much luck finding it lately. I have only been able to find denatured alcohol. Unfortunately, this type of alcohol emits a strong odor and smoke and leaves an oily residue. I was wondering if you have an idea of where I could locate the pure solvent alcohol. I would appreciate any information you can provide me. By the way, I live in Houston, Texas.

A: Pure ethanol is Everclear liquor and is highly taxed. Find a brand of denatured alcohol that has a high ethanol content of 90%. Three brands I am familiar with are Parks, True Value and Sunnyside.

Question from Anonymous
Comment dated 01/19/2011

Q: You mentioned that you also tried isopropyll alcohol, but didn't like its smell. I can get isopropyll alcohol that is 99% alcohol....better than denatured. Does the smell finally leave the wood, like denatured does?

A: I did not pursue drying bowls using isopropyl alcohol. A few people reported satisfactory results using isopropyl alcohol. Remember isopropyl alcohol is poisonous. Consult the manufacture's MSDS for precautions when using isopropyl alcohol.

The odor did disipate which is to be expected since isopropyl alcohol has a high vapor pressure. If you do use isopropyl alcohol for drying bowls please notify me of your results so I can share your finding with others.

Small rhododendron NE hollow form.

2005-11-27T01:05:00.000-08:00

Rhododendron burl from wood I was given in August. The tree had been down and cut into firewood lengths for about a week before it was given to me. The waxed blank sat outside my shop until early November when I roughed it out. I wrote the date on the bottom with a new gel pen and it disappeared while soaking in alcohol. Not all gel pens are created equal.
The data card for the hollow form. I took the piece out of the alcohol on the 12th and wrapped it but didn’t take the first weight until 24 hours later. All weights are in grams. The piece was effectively dry on the 17th when I took a long weekend. It only lost 3 grams over the next week before final turning it on the 24th. The number (224) is the sample weight of the soaking solution when I took the piece out and corresponds to 92% alcohol.
The roughed out hollow form soaked about a week before I had a chance to take it out. It was roughed out to about 1/4".
The black line on the base insicates where the inside bottm is.
Nice eyes on the low side. Base 1 1/4". Body 2 1/4 maximum and neck 1 3/4".Some flame figure on the high side. Height is 3 7/8". Top through the neck is 1/16" thick. Thickness increases midway through the body to 1/8" at the base. Finished piece weighs 33 grams.

Sanded to 600 initially and between coats. Finished with 2 coats of Rockler’s Gel Polyurethane. No buffing.

I asked about turning rhododendron a couple months ago and the advise was it will crack and split no matter what I do. I beg to differ with the advise. I also have two crotch bowls that also dried without cracking or excessive warping.

Comments welcome.

Dave

Alcohol soaking method for drying bowls.

2005-11-25T10:57:00.000-08:00

I stated looking for a method to decrease the time it takes to dry wood
bowls in 2001. By the end of that year I had refined a method of quickly drying bowls which is consistent and cost effective for both hobbyist and professional turners.

After a year of testing by other turners an article describing the process was published in the November 2004 issue of More Wooddturning. The information was disseminated Saturday November 13th on several internet woodworking forums. The thread on Woodcentral provoked a lot of discussion and answers a lot of frequently ask questions. Drying rough turned bowls quickly. A condensed version of the published article was put in the Articles section of Woodcentral on 16 November 2004. Alcohol soaking method for drying bowls.

The article has several pictures which help explain the process used to soak and dry wood bowls.

One aspect that I had not anticipated was the availability of denatured ethanol alcohol outside the United States. In Canada and the UK denatured alcohol is methyl hydrate or methanol. I do not recommend the use of methanol due to health safety concerns. It is also important to obtain a Material Safety Data Sheet(MSDS) to access the dangers of using alcohol. Both ethanol and methanol are labeled highly flammable so appropriate safety measures need to be implemented when using alcohol. Ethanol is listed as harmful while methanol is considered toxic. It is incumbent upon anyone using the alcohol soaking procedure to read, understand and follow all precautions listed on the containers. Do not do anything you are not comfortable with. The information I have provided is my experience. You assume all responsibility for any results stemming from using any part of this procedure.

More information will be added to this web site in the future. Until then please refer to the above mentioned sites for information on the alcohol soaking process for drying rough turned wood bowls.