Natural edge question

[Jim Slovik]

If you were to turn a natural edge bowl to about 1/4" thickness, how long would you have let it dry before you could put a finish on it? Would you give it a DNA soak or just let it dry?
Thanks,
Jim

[Jeff Myroup]

If you were to turn a natural edge bowl to about 1/4" thickness, how long would you have let it dry before you could put a finish on it? Would you give it a DNA soak or just let it dry?
Thanks,
Jim
I finish it as soon as I am done turning.

[JerHall]

Loaded open-ended question! What kind of wood? How green? What kind of cut - no pith? balanced grain? quarter sawn? What kind of Finish? But one answer is a few days in a paper sack indoors with nice winter heating. Or you can zap it once or twice in a plastic bag in a microwave till hot to the touch. Let it cool down a bit in the bag and then remove the bag and let the surface dry. Repeat in a few hours. Sometimes I will finish sand and put the first coat of Watco the next day. I have an empirical theory that a nice heavy coat of penetrating oil like Watco replaces some of the water that has evaporated and cuts down on minor surface cracking somewhat. More coats of Watco, with light burnishing with steel or bronze wool in between coats. When well dry (two weeks maybe) buff. You still might have to attend to some cracks or bark separation with filler (instant coffee maybe and thin CA.) It's all an experiment. Turn several such bowls. And vary your strategy. Evaluate. There is no one "right way." Woods of different species and even trees vary a lot in behaviour. In my area Oak among the easiest, Madrone among the most difficult. But 1/4" thick walls in say an 8" diameter bowl gives you a lot of room for the wood to freely wiggle without much cracking.

[Chip Sutherland]

How wide is your bowl? If it is green wood, you may have turned it too far at 1/4" thick. The general rule is to turn the thickness to 1/10 of the width of the bowl (eg. 10" bowl/1" rim thickness). Then use one of the drying techniques which for me is DNA. However, I think all my NE bowls were dry. If you've gone too thin, I'd toss it in DNA to remove as much moisture as possible anyway.

You will likely see some warping as it dries. If you are lucky it will just enhance the piece. Otherwise, you can wedge some dowels on the inside of the bowl to control some of the warping, then tape them to stay in place. I've heard heavy rubber bands work but on a NE, I would think they would just pull the high ends inward and bow out the sides.

Wrap the bowl in brown paper put it in a bag. Check on it regularly to see if the dowels shift and fix as needed. Purest will weigh the bowl before and during the drying process to see when the weight loss plateaus. Duh...I don't have the time. I just flipping guess but I give it at least 4 weeks.

Depending on the amount of movement at the tenon, you may be able to re-mount the bowl on the lathe and do some light finishing. Had it been thicker, you would just re-turn the bowl with heavier cuts and eliminate much of the warping. If you cannot re-mount the bowl, get out the sand paper and finish it the hard way. Call it an educational moment.

As for finish, I like my NE's to be the true color of the wood so I turned to mineral oil as the tung oil finishes alter the color slightly. Takes mineral oil a little longer to cure but that's my 1st choice. 2nd choice is a WOP...cuz I'm lazy and ready to move on to another vortex project.

[William Bachtel]

As soon as I am finished sanding I put the finish on it, I have never had a problem, doing it this way. All my N/E pieces are turned green. General Finishes.

[Jim Slovik]

Thanks for the responses. The natural edge bowl I'm planning on will be walnut using a piece that is 6-8" in diameter. Very green. Any special concerns with keeping the bark on walnut?

[Bernie Weishapl]

Haven't had a problem much with keeping bark on walnut. Of course a lot depends on when it was cut. I have better luck keeping bark on when the wood is cut in the winter. Also when I do a NE I turn to finish, sand and soak with Antique Oil. I have never had a problem with cracking and not much warping either.

[Faust M. Ruggiero]

Jim,
If you don't mind the natural warping the bowl will do when it dries, sand it wet, clean up the bottom and give it a soak in DNA. One day will easily give the DNA time to do it's thing and won't raise the grain too badly. I am sure a light sanding after a week of drying will make the surface ready to accept finish. The DNA will not affect the bark unless it is already loose.
faust

[Reed Gray]

When I first heard about the DNA soaks, maybe 8 years or so back, I got set up for it and dried a lot of bowls that way. I turn everything green, to final thickness, and let them warp. I found out that, for the thin turned bowls, the DNA has no measurable or observable effect on drying thin turned pieces. It does seem to make the wood more difficult to sand out. On twice turned pieces, it may make a difference, and a lot of turners swear by it, but I have never experimented with it in that way. Walnut is a very stable wood for drying, and I have had minimal warping and cracking problems. I would not put dowels on the inside as if the wood tries to shrink, the dowel won't let it, and it will be stressed, possible to the point of cracking. Probably best to bag it, or at least start it out on the floor in a cool draft free place. Dry enough to sand in about 3 to 4 days, and totally dry in about 10.

The best way I have found to keep the bark on a NE piece is to determine that I want it to come off, then it sticks like glue. If I want it to stay on, it tends to fly off, all but about 1/4 of the bowl where you can barely sand it off. Murphy's law I guess.

robo hippy

[David E Keller]

The best way I have found to keep the bark on a NE piece is to determine that I want it to come off, then it sticks like glue. If I want it to stay on, it tends to fly off, all but about 1/4 of the bowl where you can barely sand it off. Murphy's law I guess.

robo hippy

Isn't that the truth?