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Chuck I use DNA drying all the time and have had really good luck with it in 2 1/2 yrs. I have only lost one bowl. I turn the bowl down to 10% of the width. A 12" bowl I will leave the walls 1" thick so when it warps or moves you can get it back round again. I most generally don't go any thinner than 3/4" no matter how small. I let mine soak 48 hrs or so. I have left them in a week when I forgot with no problems. I take them out and let them flash dry (till the surface is dry). I then wrap them in brown grocery sack like a Christmas present taped with masking tape. In the bowl part I cut it open just to the edge of the bowl lip. I got several cooling racks from wal-mart for a couple of bucks each and turn them upside down in a coolish (not hot) place where there is not much air movement. I leave them to dry from 2 to 4 weeks and they are ready to go back on the lathe. I put the inside of the bowl up against the chuck since you have to finish the inside anyway, bring up the tailstock to hold it and true up the tenon. Turn it around and finish turning. Here is a site by Dave Smith that I followed pretty close. Hope this clears some things up and helps.

http://www.woodcentral.com/cgi-bin/readarticle.pl?dir=turning&file=articles_473.shtml
 
My version of Bernie's answer:

How long does it need to soak to displace the water?

24 hours, plus or minus. Plus is better than minus. Like Bernie, I've forgotten a few in the drink for a week or so with no ill effects.

How long does it take to dry after?

Again, as Bernie said, usually about 2 to 4 weeks. I don't have a moisture meter, but I figure it's pretty much dry when it's no longer cool to the touch. (That's probably less scientific than a divining rod, but so far it's worked for me.)

And what is with putting it in a brown paper bag?

Because it looks so darned cool. :p

The idea behind wrapping it is to regulate or temper the drying...to slow it down a bit, but not too much. I'm different from a lot of guys on this. I tend to wrap a piece in 3 to 6 layers of newspaper, taped on however it'll stay, and I don't cut the hole in the middle like a lot of folks do. But, there's usually an air gap there, since I stretch the paper across the opening of the bowl instead of fitting it to the inside contour. On bigger pieces that are too big to fit within a single sheet of newsprint, I'll sometimes double or triple bag them loosely in brown paper bags, using the second bag to cover the opening of the first. I dry mine inside the house, so they are treated to heat in the winter and AC in the summer.

I know a lot of guys are much more meticulous than me about how they wrap and store their drying pieces, but so far I've had a good success rate.
 
I guess my answer to that Chuck would be I don't know. I have never tried it that way. I always have just wrapped and taped it up then cut the opening in the bowl part. Date it and turn it upside down on a cooling rack. I really don't know if that would work but I think now that you mention it I will try it on the next one I turn.
 
Ok so to see if i have this right. One would fill a bucket with DNA and soak the piece in it. Not paint it on. Let it swim for a day Then take it out and let it sit until it is dry to the touch (guessing 5 minutes or less) Here is where I get fuzzy Could One just stick the piece in a brown paper bag or does the paper need to touch the surface?
You're right on target...it swims in the bucket for a day or so. (I often use some lead fishing weights to keep the bowl from floating.) Seal the bucket with a lid. (I eventually got one of the screw-top lids for storing dog food and other dry goods.) When your pieces are too big for a 5 gallon bucket, there are other approaches. (I need to post a thread one of these days about my big vacuum-sealed DNA tub.)

After pulling it out of the drink, I let it dry a bit. Sometimes a few minutes, sometimes a few hours until I remember I'm supposed to wrap it up. From what I've seen, a tight wrap is no different from a loose wrap. You can just put it in one or two paper bags, with the openings rolled up or taped shut. I'm very lax about the exact wrapping procedure, and I've seen no real difference between one method or another. As I mentioned earlier, I usually use newspaper, but that's just because I've usually got more of that around the house than brown paper bags.

I really don't think it's as exacting of a science as some like to think. Thing is, even under the most careful laboratory conditions, no two pieces of wood will react the same. So nobody really knows what's the best way. They only know (and tend to stick with) what works best for them. Mess around a bit with a few variations and see which one seems to feel best to you.
 
I have tried this on only one sycamore bowl, I soaked it for 24 hours and then only covered the inside of the bowl with paper sack. Guess that is totally opposite from what Bernie said, but it worked. It has been siting on top of my refrigerator for 3 weeks and has no cracks. It did warp a little but nothing that can't be fixed because I left it pretty thick. Seemed to work pretty good. As soon as the mustard gets here I will finish it up.
 
Chuck,
I use the DNA method as well. I've had much better success with this method than letting them dry on a rack.

Once soaked for 24 hours or so, I let mine dry for 5-15 min to allow the alcohol to flash off. Then I bag my pieces in grocery sacks with the top of the bag folded 2-3 times to seal it and leave them to dry. In your climate (NH) this process should work well. In drier climates you may need to double up on paper sacks.

DNA can be purchased from paint stores in 5 gal containers for as little as $35. Big box stores charge $14/gal (ouch). Sometimes your local hardware store like Ace will have the best prices at $8/gal.

Dave Smith has written articles on the subject and is very knowledgeable. Here is a link to his post on WoodCentral:

http://www.woodcentral.com/cgi-bin/readarticle.pl?dir=turning&file=articles_473.shtml
 
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