Drying Peppermill Blanks

Several weeks ago, I asked on this forum about drying wet turning squares to make peppermills. The advice was it would be better to use kiln dried wood.

My R&D background led me to run some drying tests on several wet (30% MC) 3x3x12 squares. Sample 1 was maple rough turned to about 2.5 inch diameter and a 1 inch hole was drilled through the center. It was then soaked in DNA for 24 hrs, placed in a paper bag and set aside to dry. Sample 2 was treated like the first sample but not treated with DNA. Sample 3 was a soft wood (red gum) and treated like sample 1 (including DNA). Sample 4 was a 3x3x12 redgum square and then boiled in water for 3 hours (just to see if the boiling water method would work with thicker wood).

Sample 1 was allowed to come to constant weight and at this time (20 days), all the samples were weighed and measured. The results are:

Sample 1 lost 20% of its weight-no cracks observed. The difference between the maximum and minimum outside diameter (outside deviation) was 0.02 inch. The difference between the maximum and minimum inside diameter (inside deviation) was 0.02 inch.

Sample 2 lost 13% of its weight. The outside deviation was 0.06 inch and the inside deviation was 0.04 inch.

Sample 3 lost 22% of its weight and the outside deviation was 0.09 inch and inside was 0.05 inch.

Sample 4-complete failure--checking and very slow weight loss.

Hope you find this info useful. Not as exhaustive as it could have been but it does seem to suggest that drying wet peppermill blanks without excessive checking or distortion is possible. Obviously, returning and redrilling to get the final peppermill would be required.

Hello Charles,
after all is said and done, if sales are your objective, isnt it cheaper to buy kiln dried? If it isnt, then you contributed a good service.Since I live in Texas, I am using Mesquite, and the only loss of time for me is to wait till the next day for the surface moisture to dry, then apply the finish that suits the mill.
Anyway, that is how I do it. By the way, where are you?Max

I have made several now for wedding presents. I wouldn't use anything but kiln dried lumber. One I made from Mara was 24" tall. There was a lot of heat generated by the forstner bit going 22" into end grain. I would think if there is too much moisture that would crack or warp over time. The best that you can get with air drying is reaching equillibrium where you live. If you send that pepper mill somewhere where the climatic conditions are quite a bit different than where you live there will be trouble. Once wood reaches equillibrium where you are located it doesn't get any drier. THat point is usually reached in 6-8 months and wood doesn't get any drier no matter how long it sits.

I hope that helps.

Quinn

I have made perhaps a couple hundred mills, mostly for craft sales, some gifts.. At first I bot all my blanks at CSUSA or WC. TOOO Expensive, leaving no room for profit. Recycling $'s is not my idea of profit.
I traded pens and pepper mills for 8 logs from a sawyer and he cut them into 14/4 sticks, with remainder in 5/4. Now air drying in back yard. Should be ready for topping off in a kiln late Spring.
I will try DNA before taking to kiln so your comments are very timely. I will experiment with boiling water also, to see if air drying first changes the outcome from yours. Very timely post for me. Thnks

Harvey, I don't sell anything-just interested in using some unusual wood I have (I'm located north of Tulsa).

Quinn, you are correct about equilibrium MC-I just give them away around here so not too concerned about big changes in MC (if they move to another location, they lose their money back guarantee;)).

Brian, I find kiln dried 3x3 turning stock is not always readily available and not always cheap. I recommend the DNA treatment and the hole in the center really speeds things up-good luck.

Charles - Thanks again for the timely post - I will try DNA as soon as I can get a stick of Walnut out of the snow. I'll try to remember and let you know how it turns out.;)

Brian, hope it works for you (looks like I'm not the only one who keeps crazy hours:)).

I know nothing of using DNA, and I am new to the turning game. But, I have used a lot of air dried and kiln dried wood over the years. Quinn is correct on his points on equilibrium. And, I would add that regardless of the drying method used wood will always "move" with changes in temperature and relative humidity. It will always seek an "equilibrium" given those two conditions.

I prefer air dried wood for a variety of reasons, but if I make a piece in KY, of air dried or kiln dried, and ship it to Arizona, there will be changes in that piece. For that matter, a piece will change seasonally, as well, even in the same geographic location.

Brian, I know that you don't want to wait the 3-4 years on the walnut to air dry, but it has such a beautiful color and better texture when not kilned!:)

Charles, interesting experiment! Sounds like it has merit if one is not into production mode.

You may have left one factor out of the experimentation procedure - mother nature. To make a more conclusive test you need to use 10 samples at least (per treatment) and have blanks come from various logs of the same tree. The same treatment may work for one piece and not for the second. They are after all quite different.
You may be able to get years of experience summed on both DNA and boiling online.
Thanks,
Norm

Norm, you are absolutely correct. If I was still doing this sort of thing for a living, the "experiment" would have looked a lot different. I did not intend for this to be an exhaustive test but just to tell me if the squares in which I was interested could reasonably be used for a peppermill or two and thought some on this forum might be able to use this info. I hope everyone looking at these data understand the limitations of the test. I surely would want no one to use this info without also understanding the test limitations and understanding that in someone elses hands, these type of blanks might give completely different results--to coin a phrase, let the user of this techinque beware!

John, I too am relatively new to turning and suspect some long time turners will find my post rather simplistic but in my opinion, that is the best way to learn. I have been watching your turned items with great interest and am truly impressed with the turnings you have posted recently-congratulations!

Thanks, Charles.:o

Thanks Charles you have saved me alot of time.

Charles,
I remember reading a study by Steve Russell on drying with different methods( hundreds of bowls).I know he covered bagging, boiling, dna soaking, and a few others.I tried to find the link in his on-line lathe talk -(which is a great free monthly resource) but was unable to find it. I know a lot of other creekers follow his newsletter, maybe one of them has the link?
Tom

I found the link to boiling by searching the creek
http://www.sawmillcreek.org/showthre...=steve+russell