the booze drying method, part...??? (long)

Re: the booze drying method, part...??? (long)

Dick Parr

>Tony I store mine in the shop, but I have gas heat and keep it around 56-58 when I'm not in the shop and 60-65 when I am in there, unless the sun is out and then it could get as warm as 75 before I open doors. I have two cherry bowls ready to finish as of yesterday and today (only soak one bowl at a time). A quick look today and the they looked good. Both show about 10-12% moisture content after drying for 10 days. I have processed 10 box elder bowls and 1 cherry bowl doing this process and have not lost any. All have cleaned up nicely and don't show any movement since finishing.

Good luck

Dick

Re: the booze drying method, part...??? (long)

William

>Tony,

I too, am in the process of drying some fresh cherry and as I write this, I have VERY fresh sycamore being soaked. Sycamore is notorious for not playing nice.

After soaking and drying, I wrapped them and stored them on a rack in my basement. The basement is on the cool side year round. So far it's been pretty good. I have noticed slight warping, no cracks.

The three cherry blanks have been drying since 12/16. The first couple of days, they were losing weight very quickly. Now it's about 1/8th of an ounce every several hours. So I haven't hit equilibrium yet. I had a 4th bowl that should've dried a little longer and I finished it. It has since warped slightly.

I am going to wait until I hit a steady weight for a 24-48hr. period.

William

Some thoughts about this

Dominic Greco at home in Richboro, PA

>Tony,

I hear you about the cherry blanks cracking at the slightest provocation. But then again, most fruitwoods (pear, apple, cherry, et) are like that.

I was reading your post and had some thoughts as to the cause of the cracking. My thoughts were that the cracking you're experiencing may not be the result of the alcohol soaked wood drying too fast. Rather, it may be from unequal stressing of the wood fibers. Allow me to explain:

When I first started turning, I lost a good amount of my roughed out cherry/pear bowls to cracking. This was not, as I first thought back then, from improper drying. I was wrapping then just as I had been taught. It was from cutting the bowl blanks with the grain "imbalanced".

When cutting up your log for bowl turning, you need to balance the way the grain will be on the blank. You should not have grain that is tightly spaced on one side, and widely spaced on the other in the same blank. You're asking for it to crack. The stresses will not be "equalized" when it dries and that's how a crack develops. I think that is what is happening to you.

I was included in the original group for Dave's Alcohol Soaking Technique Test. I tried it on some of the nastiest wood I could find (apple, cherry, pear, walnut, hickory, maple, osage orange, sweetgum, and sycamore). But all the blanks were cut with the grain as balanced as humanly possible. None of the blanks developed any cracks that were anything other than small surface fractures (which were easily turned away).

Bill Grumbine talks about balancing the grain in his video "Turned Bowls Made Easy". Another great DVD to view is the "Ascetics and Properties of Wood" by John Jordon. Both will explain it much better than I have.

See ya around,

Dominic

Re: Some thoughts about this

Tony Costine

>Hey Dom!

Thanks for weighing in. I've gotta tell you though, I try my hardest to line up the grain so it's even. I don't get the same sort of cracking on cherry that air dries.

In fact, I've never had any problem with cherry, unless it was something stupid I did...like leave the bottom too thick or whatever.

I don't know...it just seemed to me that 3 ounces in 24 hours might be a little quick, especially when you add in that the bowls came from being soaked in 30ish degree alcohol for a few days, then being set to dry while the shop temp was in the mid 40's and then inside where it's around 70 and dry--the woodstove dries everything like crazy--might have done it.

Also in the two blanks that cracked the grain was just a tiny bit curly--I thought the alcohol would take care of that, from what I've read. The straight grained bowls haven't cracked, in fact have barely warped.

The one that cracked the worst--really split--was around 5 inches and shallow. The other two that had the "stress cracks" were 6 and 8. All were taken to a half inch thickness.

I'm sure the process works, I'm just trying to figure out how best to work with it!

Thanks again,

--Tony

Re: the booze drying method, part...??? (long)

Doug Trembath

>Man, Tony, this stuff can get frustrating, can't it?

I think part of your problem can be attributed to drying in your house, in that the humidity level drops significantly with your type of heat. I've dried hundreds of bowl blanks, but never used the alcohol. It seems to me, though, that the alcohol will only accelerate the moisture loss, not control it. I rough, coat with Anchorseal, and store in an area that has the least air movement, in the lowest area, and wait until they're dry. I use an unheated small garage, or tractor shed, that was on my property when I moved here to store most of my wood and roughouts. I lose maybe one in a hundred blanks without boiling, alcohol, etc.

It stands to reason, however, from following Dave's protocol as it has been explained here, that you need to try to control the amount of evaporation on the outside of the bowl to help even out the tension in the blank. I agree that 4 oz in such a short amount of time is probably too much, and is contributing to the problem. The lower the temperature and the the higher the humidity, the slower the alcohol should evaporate, it seems to me, and vice versa. Try wrapping just the bottom of the bowl, placing them bottom up in a low area with relatively little air movement, and see if that helps. I learned my method from Mike Mahoney years ago, and took a hint from his choice of area to store them, which is a sub-basement in his wonderful old house in semi-arid Utah, where the relative humidity is very low. They lose moisture much slower this way, but I doubt if Mike has many crack, similar to my own experience. If you apply this reasoning to the rapid drying of the alcohol soaked bowls, it may help you in your experiments.

Doug Trembath

Studio in the Woods

Re: the booze drying method, part...??? (long)

Mike Schwing from Md.

>I have a few thoughts on this, too, of course.

First, I'm not sure why there is a thought that alcohol drying might help minimize cracking, but it seems to be a rumor if not an urban legend. I'm no scientist, nor chemist, but it just seems to me that the alcohol based drying simply alters the speed at which moisture is lost, nothing more. As it accelerates this process, I would tend to think that it would worsen the cracking.

My own experience in drying blanks as well as roughs has been very positive, both with anchorseal as well as alcohol. Everything gets dried out in my basement, which is always cool in the 60's F range, and has a year round moisture reading of 40-50% RH. In these conditions I can dry/store whole round blanks of silver maple and poplar without anchorseal or any other preparation - no cracks. Cherry and fruitwoods have to be waxed on all sides. Rough turned items are treated the same.

Since beginning to use the alcohol drying method I have had the same positive results - losses have been about the same - but I have not been coating or paper bagging any of them - just setting them on the shelf in my cool, moist basement.

I believe now that I have played with the alcohol drying method for several months that my conclusion is I'm in no hurry to dry things, and I'll stick with anchorseal. If I was in a hurry, I'd use alcohol.

Re: the booze drying method, part...??? (long)

Dinyar Chavda

>Mike:

You're being facetious, right?

You say "I'm not sure why there is a thought that alcohol drying might help minimize cracking, but it seems to be a rumor if not an urban legend." I remembered the impression I got reading the original posts on this approach, and went back and reread them. I am totally confused, and would like some clarification.

While there was no claim of 100% success in terms of splitting/cracks, etc., there were statements like "There have been some failures but they have been rare exceptions". In response to a comment that the person had " lost 5 bowls so far, which stinks big time", one of the early proponents said, "I decided to REALLY give his technique a try. I've been using this technique ever since with a great deal of success." And, one of the clearest statements was "Once I started wrapping the bowls on the outside the failure rate dropped to nearly zero."

To be fair, there were occasional stements about the fact that it "limits cracking", but, in general, my understanding was that this process reduces drying time, and "almost" eliminates cracking, which is what one would hope that any drying technique would do (otherwise, we could just bake the wood in an oven!)

Subsequent e-mails by more recent triers have reported failures, which have been attempted to be explained away by sap pockets, and imbalanced grain.

While one can infer that alcohol reduces/eliminates cracking, I'd like to obtain a definitive statement, and would like to have the following question answered. Which of the following is the true state of affairs:

1. The alcohol drying reduces drying time dramatically, and eliminates cracking and checking.

2. The alcohol drying reduces drying time dramatically, and cracking and checking is comparable to normal drying techniques of coating end-grain and wrapping, etc., i.e., approximately _ %.

3. The alcohol drying reduces drying time dramatically, and cracking and checking is reduced to approximately _ %.

The reason for my caution and persistence in this regard is a comment that Russ made to me, in which he expressed some concern about the impact of inhaling alcohol fumes over long periods of time. Given that I work in an unheated garage which is closed most of the winter, and that the drying bowls would also be stored there, I am concerned about this (my body also does not react well to alcohol), and want to have a clear pictre of cost vs benefit in my mind. I was not worried about the LDD process from a safety viewpoint (other than getting prune fingers). Likewise, the boiling process can also pose a danger, and I appreciated Steve Russels' clear description (in Woodturning Plus, a non-scientific journal)of what it is that he did and what he was able to achieve in his experiments.

It seems to me.............

Russ Fairfield

>Although they are related, drying rate and cracking are two different issues.

Drying is the removal of moisture from the wood by evaporation on the surface of the wood. That is one problem.

Cracking is the result of internal tensile stresses that exceed the strength of the wood. That is another problem.

One of the causes of these tensile stresses is wood shrinkage as the moisture is removed during drying. Other cracks, also caused bt moisture evaporation, start as soon as the tree is cut, long before we ever put it in the lathe. Cherry starts getting visible end-checking (small cracks) out from the pith within 5-minutes after cutting the tree. Then there are the cracks from wind and growth stresses within the tree, and these can be a karge number in some species.

The only sure ways that I know to eliminate cracks are, preventing them from happening BEFORE we put it on the lathe, and doing what we can to prevent them from happening AFTER we have removed it from the lathe.

If the cracks happened between the standing tree and the lathe, there is no way that we can put them back together again except with glue. There is nothing that we can soak the wood in that will make it grow back together again. These cracks we have to live with. I am beginning to believe that the greater majority of the cracking we experience is of this type.

Those that happen after the lathe can be controlled by:

1.Turning the wood to a thickness and shape such that it can shrink and move without developing any tensile stresses that are greater than the strength of the wood. Yes, it will warp, but it won't crack.

2. Remove the moisture during drying such that the wood can adjust to its new shape and size without exceeding the strength of the wood. We usually do this by slowing the drying rate with barriers (wrapping with paper) or controlling the environment around it.

3. Internal stresses can be relieved by softening the lignin that bonds the wood together. The only way that I know how to do that is through heat. Lignin is not soluble in alcohol, that I know of.

Yes, alcohol can be used to dry the wood faster, because the alcohol soaks easily into the wood where it will absorb the moisture in the wood, the new alcohol/water solution will behave like an alcohol and move more freely through the wood, carrying the moisture to the surface where it will evaporate. If it can do that while not letting the internal tensile stresses exceed the strength of the wood, it can be done without cracking. I don't believe it can. There are other things that have to be done besides just soaking the wood in something.

There is no free lunch, and there is no magic elixer that will solve all of our problems.

Re: It seems to me.............

Tony Costine

>Okay, so what is optimum? I was taught (self taught, but studied firmly at the page of Mr. Raffan) and my own experience has borne out that: small bowls seem to warp more than large ones--everything else being equal, and perhaps small bowls should be roughed thicker to compensate.

So everything under 6-8 inches becomes between half and 3/4 of an inch.

I attempt mightily to maintin a certain thickness, sometimes even leaving the bottom thinner than the upper walls--because others have reported success with that.

I'm not sure what else I can do.

I'll further state, for the record, that the hemlock I soaked didn't crack or check. The beech didn't either. So one could it down to cherry being "notorious", yes?

Hey, it's all process, and it's all interesting. I'd just like to be able to get a better handle on the whole thing!

--T.

Re: the booze drying method, part...??? (long)

Mike Schwing from Md.

>Not really Dinyar. I didn't keep paper records of what I've done with alcohol, so the only records are what I might have posted and what my brain can accurately recall (but who knows?). My brain tells me that the alcohol soak does indeed speed up the drying time, but that cracks/checks occur at about the same rate. I guess I'd pick number 2 on your list.

Right now I have a few 12" maple burl platter blanks soaking in alcohol. I'm going to leave them in for a week or so. My goal is to allow them to dry completely as blanks and resell them. Dry, ready to turn maple burl blanks are very valuable. Plus, I have another pallet of maple and madrone burl at the shipping depot waiting for me to pick up.

Anyway - since maple burl is very stable on its own, I expect that they'll fully dry out within a few months.

Other than that, I don't plan on using the alcohol drying method any longer. It works well enough, but as stated, I'm in no hurry, and would prefer to let Mother Nature dry my stuff out on her own with just a little wax barrier.

BTW, my 5 gallon bucket of alcohol sits outside, and the first day of drying after soaking also occurs outdoors. I don't like the smell either. You've been in my basement - too small and confined for noxious gases.

Re: the booze drying method, part...??? (long)

Dinyar Chavda

>Mike:

My question re your being facetious referred to the "rumor and urban legend" (that alcohol drying reduces cracking. To me the source of that "rumor /urban legend" was the the statements made in the earlier thread.

What you are saying actually does make more intuitive sense than the earlier threads which, at least to me, made it seem like alcohol-drying would reduce (almost eliminate)the failure rate, even on problem woods. Careful reading of the thread shows that you had never made that claim, and so you are being consistent in what you say. However, it makes me wonder what the experience of the other testers was. While I would certainly try a method that did reduce checking (given what I make, I'm not as concerned about warpage), I would hesitate if all that it did was speed things up (which I can do in a microwave, and, like you, usually don't care to)

Dinyar