For those interested in DNA drying

[Dave Smith]

I have been documenting the drying of several bowls on my Alcohol Soaking blog. Lots of pictures and some graphs. I will be adding more as time permits.

If you know this process doesn't work then don't bother viewing to the blog.

Dave Smith

Sunshine, is this really Longview, WA?

 

[Bill Boehme]

And, what is the URL of your BLOG for those of us who don't know?

Bill

 

[Dave Smith]

Alcohol soaking blog

http://alcoholsoaking.blogspot.com/

 

[MichaelMouse]

I have been documenting the drying of several bowls on my Alcohol Soaking blog. Lots of pictures and some graphs. I will be adding more as time permits.

Sunshine, is this really Longview, WA?

Your blog is a fine documentation of evaporation. Having been to the area, I realize that what we elsewhere take for granted, that water evaporates, may not be a given up there.

Wouldn't happen to have gone without alcohol and documented that evaporative process, would you? Here a (actually the last eight) cherry bowl cut to 1-1.125 thickness dries from flinging green to 14%, the limit, given the relative humidity, in ~6 weeks. No alcohol, of course, though it would require a violation of the laws of chemistry and good sense for alcohol to make water evaporate faster or replace bound water in the wood. Hard maple takes a couple of weeks longer. Shrinkage is in line with the fine figures prepared through the comprehensive research of the FPL in Madison, as is the dry time.

Time to compare apples to pickled apples and see, because there seems nothing remarkable to be had for the expense.

 

[Ron Sardo]

I have been documenting the drying of several bowls on my Alcohol Soaking blog. Lots of pictures and some graphs. I will be adding more as time permits.

If you know this process doesn't work then don't bother viewing to the blog.

Dave Smith

Sunshine, is this really Longview, WA?

Thanks for the info Dave
Your process has always worked well for me

 

[Joe Fisher]

Time to compare apples to pickled apples and see, because there seems nothing remarkable to be had for the expense.

This is something I've wanted to do for quite some time.

I'm a skeptic and an engineer, so I had to test DNA drying for myself. I'm keeping a log of my actions here:

http://www.fisherwoodcraft.com/dna_test.php

I hope to update it daily, or at least as anything interesting happens.

-Joe

 

[Dave Smith]

Good luck Joe

I tested various ways to dry wood several years ago. Once I realized that nothing worked as well as alcohol soaking I concentrated on refining the process. Several people have kept data on drying bowls using alcohol soaking and their charted data was the same as the graphs on my blog. The protocol I have developed was not a hit or miss, guess and by-golly process as some seem to think.

I am glad you are doing the test because engineers have to do something while operators make the plant run. I spent a few years of my life with a Senior Reactor Operators License so you can see where I am coming from. If it works do it. If it doesn't work blame the Engineer.

Dave Smith

Time to take the chicken off the grill in Longview, WA.

 

[Joe Fisher]

I am glad you are doing the test because engineers have to do something while operators make the plant run.

Har har. 🙄 We're all friends here; no reason to take shots at my profession.

Let me make this clear, since your posts are coming across as defensive:

I don't doubt that your results were arrived at after much testing.
I don't think you pulled the method out of thin air, or a body part.
I don't doubt that you get the results you claim.
I don't doubt that other's results match yours.
I don't have any preconceived notions about what the results are going to be.

I'm a curious person. I've seen many, many claims of the magic of DNA drying, but I've never seen anyone test it against drying without DNA. I'm curious to how much of a difference there will be. I'm sure other turners are, as well, so I thought I'd share it.

Either way, I should get at least one finished bowl out of the deal, eh? 😉

-Joe

 

[Dave Smith]

Engineers are people?

I got nothing against engineers, my daughter is an engineer. Still trying to figure out where I went wrong.

I am a skeptic also. But with the scientific method you should be able to use the same procedure I used and get the same results. So I have no doubt you will get at least one bowl to finish turn. I would have turned the bowl to 5/8" wall thickness. Less thickness results in less stress across the wall. One of the most useless test questions I had on annual NRC license exams was to describe the stress changes across the reactor vessel during heat up and cool down. But that knowledge lead to the idea of wrapping the bowls in paper to keep the outside under compressive stress thus minimizing cracking.

Good luck.

Dave Smith

Doubting that Avogadro really counted that high in Longview, WA.

 

[MichaelMouse]

I'm a curious person. I've seen many, many claims of the magic of DNA drying, but I've never seen anyone test it against drying without DNA. I'm curious to how much of a difference there will be. I'm sure other turners are, as well, so I thought I'd share it.

I think you should have a couple of good ideas about what the results will be. Note that you're using alcohol enriched by distillation. Means that alcohol certainly doesn't accelerate evaporative water loss, but follows Raoult's law. Else distillation would be impossible.

Chemistry also says that the privilege of the hydrogen bond (bound water) goes to the more ionic compound. That's water, so alcohol shouldn't replace it chemically. If it does, all those vintners, distillers and brewers who've been storing their product in wood barrels have been watering it down all these years. The cask of amontillado would just be dilute grape juice.

 

[Andy Coates]

really?

But that knowledge lead to the idea of wrapping the bowls in paper to keep the outside under compressive stress thus minimizing cracking

Did you really intend to type this sentence? Surely you're not suggecting that somebrown paper and tape can provide enough "compressive stress" to prevent cracking? After all, the wood will begin to shrink almost immediatley, and as you say yourself in an earlier post, the paper becomes baggy due to to this factor. So where is the compressive stress? Any anti-stress compression would surely need to be provided by a material, rig, set-up that itself is stronger than the material in which the cracking was likely?

I'm not convinced so far by the claims for DNA as it is, but this claim seems even more spurious and doesn't help the debate.

Andy

 

[Ron Sardo]

Surely you're not suggecting that somebrown paper and tape can provide enough "compressive stress" to prevent cracking?

Andy

I think what Dave is saying is that the brown paper will slow down the evaporation on that side of the bowl causing the "drier" side to compress.

 

[MichaelMouse]

He may be saying it, but the open interior of a shape attempting to shrink in diameter will always and has always been under compressive stress. As the tangential shrinkage resulting from loss of bound water places the wood under such stress, coating the inside or wrapping it inside makes no sense. It couldn't split if it wanted to. How many have had bowls crack inside out?

All shrinkage, as politics, according to Tip O'Neill, is local. Round up four of your friends and grasp hands. Now pull. See what happens when you're in the middle versus on the end. Same thing happens to wood that has nothing but air to grip in one direction.

 

[Dave Smith]

Hi Andy,

I didn't type out the entire process because I have explained it in the original article and in subsequent post. The paper on the outside slows down the evaporation of moisture compared to the inside. The outside surface area is larger than the inside thus loses moisture faster. As the wood drys it shrinks and will pull apart under tensile stress on the outside leading to cracking. If the outside drys slower than the inside it will under go compressive stress as the inside drys. The outside will undergo the compressive stress as the inside is contracting.

Wally Dickerman has been drying bowls roughed out bowls for years by applying wax to the outside only. I found this out after I started to wrap the drying bowls in paper to reduce the cracking encountered when drying bowls in a paper bag. Wally says he has very few failures using his waxing method. He lives in a very dry area of Arizona.

Andy feel free to contact me if you would like to further discuss the process.

Dave Smith

Spent too much time on the forums already this morning in Longview, WA.