dna

[allen thunem]

I have been reading the posts and questions on dna for drying wet wood.
I have two questions that may have already been asked but am gonna ask em again.
First is in regard to "nesting" wet wood in shavings.
Can or will someone explain this method to me in detail?:confused: i.e. how deep the savings need to be, how much of the turning needs to be covered, how wet the shavings need to be etc etc.


Secondly I assume most of you rough turn and then immerse your turnings directly into the dna for drying without sealing with anchor seal or whatever your chosen sealer is.
Sorry if I am beating a dead horse.

[Ken Hill]

I take a brown grocery bag, fill it 1/4 way with the shavings from the rough out, then place the rough out in the bag, cover it with more shavings, shake the bag then fold the top over taught and staple it shut. There is a few inches of shavings surrounding the bowl, and yes, no sealer but I would imagine some will still use sealer on endgrain or maybe on a highly figured piece or one that is prone to cracking.

The DNA soak uses no sealer, just immerse and keep it in there until you decide its had enough.

[Steve Vaughan]

Allen, I think you're asking about this - Sometime, when my rough-turned bowl is larger than my 5 gallon bucket, I'll use the shavings to create a nest. I'll fit the bowl into the pile of shavings, with the top of the shavings above the edge of the bowl. Then, I'll take the bowl out of the nest I just created, put it in the bottom of a trash bag, and set the trash bag with bowl back into the fitted nest. Then I'll pour the dna right into my trash bag, filling the outer edges of bowl, and putting a good quantity in the middle of the bowl. On the outside of the bowl, because it's fitted into a nest of shavings, it will not require much dna at all to get coverage. I don't usually fill the inside of the bowl completely, and I'll twist my trash opening up tight to get out most of the air. I do like to leave a little bit of give in the bag so I can go to it every little while and splash the dna all over the inside of the bowl (because I didn't fill it up completely). Hope that helps.

[Lee Koepke]

I think the basic theory behind drying is consistency of airflow and creating the most even environment for all surfaces to dry at the same rate. so the reason for shavings is to keep part of the bowl away from the paper.

Here the paper snugged up against the bowl, may allow for more vapor transmission in that specific area of contact, so the chips help with the even-ness of the drying

[James Combs]

Maybe to clarify things a little more (or muddy the water, not sure) but there are two steps to the DNA drying process. Well four if you consider rough turning as the first step and finish turning as the last step. After rough turning so that the thickness is about 10% of the width of the bowl or vessel it is placed into the DNA. Either directly in a large container or the nested plastic trash bag method noted above. In either case it will remain in the DNA from a few hours to a few days depending on the overall size of the turning. After the soaking time it is allowed to "flash" off the wet DNA for maybe an hour and then it is put into a brown paper bag that covers the outside of the vessel. The center/inside of the vessel is left exposed to the air. There after drying time is a few days to a few weeks.

If the DNA process is not used then the DNA soak/flash-off is skipped but the bagging process is still used. As noted above some put shavings into the bag others do not. But the over all attempt is to slow down the drying of the outside surface to prevent stresses on the outside. Drying on the inside first put stresses on the wood that tend to pull it together where as on the outside will tend to pull it apart. (or so I have heard and read) If the DNA process is skipped then the vessel remains in the bag/chips until dry, typically several months.

[Barbara Gill]

Maybe to clarify things a little more (or muddy the water, not sure) but there are two steps to the DNA drying process. Well four if you consider rough turning as the first step and finish turning as the last step. After rough turning so that the thickness is about 10% of the width of the bowl or vessel it is placed into the DNA.

Actually according to the original instructions the bowl should be <10% of the width for the denatured alcohol soak.

[Carol Kinney]

Hello Allen,
This is the process I go through and for the most part (except with less detail) have this posted so I can follow it on my wall. Thanks to Steve Vaughan helping me when I first started, I now use much less DNA then my previous method (thank you Steve). I think we all for the most part do it the same.
Here's how I've been doing the DNA method:
DNA

1. Rough turn piece leaving it about .75 to 1.5 inches thick in all areas (some say leave bowl less than 10% - I just keep it simple). My only bowl that has cracked using DNA was from it being too thin (it was less than 1/2 inch) – I just make them a little thicker now.

2. Get a container and put a bunch of shaving on the bottom and sides. The size of the container doesn’t matter as long as it is larger than the item(s) you’ll be placing in it. I use a larger sized storage containers (either 10 gallon or 20 gallon) so I can do a lot at the same time.

3. Put the bowl in a bag then place the bag with the bowl inside into the container that has the shavings. Move the bowl around to make a nest for the bowl to lie in. The shavings will come up the sides of the bag so you’ll displace as much empty space as possible which is the main purpose in doing this - the only reason we use the shavings in the DNA process is save on the amount of DNA we have to use (displacement). Other than that it isn’t necessary (before I was told about the “nesting” I used a large container and a lot of DNA!

4. After the nest has been made and the bowl in the bag is placed in the nest, I then pour DNA into the bowl – I completely submerge my bowls inside the bowl and outside the bowl.

5. After I’m satisfied with the amount of DNA I’ve put into the bag, I seal it up removing as much air as possible. I’ll move the shavings around to help displace more air at this time.

6. I normally wait 24 hours before I remove the bowl from the bag – I’m new at this so I just use a time limit of 24 hours and so far it has worked.

7. I then put the bowl on a rack upside down for 1 hour to drain as much DNA as possible.

8. Then it goes into a brown paper bag, I tape it somewhat tight on the sides so the bag doesn’t fall off then cut the paper out of the center area.

9. I check on them after two weeks and normally will turn them after a month (most likely I could do it earlier and if I needed the wood to turn I think it would be safe).

Another way I've dried my wood has been as follows: rough turn the piece, place in a paper bag then put it on a shelf. After a few weeks or whenever I remember I'll check on it. This is what I've done with most of the leftovers after cutting wood up all day - it does work . . . most of the time.
Carol

[David T gray]

i rough turned 14 12x5+ bowls, the 10 i gave out of xmas didn't crack and were turned and finished but the 4 i didn't give away and just left sitting out of the bags all cracked about a week later they were not finished :( always leave them in the bags or wait longer then 2 weeks. none of the bowls i gave out cracked.

[allen thunem]

thanks to all
that does clear the water some

[Jon Nuckles]

Carol, Thank you for taking the time to post such detailed instructions. I am saving them to post on my own wall when it is time to try this.