Rough Outs heading to the Kiln

[Bob Bergstrom]

These were turned over the past couple weeks. They were stored in a contractors bag. I achor sealed them and will take them to my Woodturners club's workshop and put them in a converted upright freezer. I will start with a 40 watt bulb. Last time I loaded it with walnut. And over a period of 5 weeks they dried to about 10%. As the weeks progressed the temperature rose from 80 degrees to over 120. I prefer to load as many as possible to keep drying slower than it would be with a small number of bowls. I will also wrap the oak bowls in paper from lawn waste bags. After three weeks I will turn on a small fan located insid on the door. Bowls are oak, walnut, ash, cherry and soft maple.
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[daryl moses]

Looks to be a good assortment of sizes and species. Anxious to see the results after they have been completed.

[Steve Doerr]

Nice job. I'm sure your club members will really appreciate it.

[Dave Fritz]

Do you notice less movement doing it in a kiln over just air drying?

[Peter Blair]

In addition to Dave's question I wonder about what percent do you get without cracks and how long had the tree been cut down before you roughed these out?

[John Keeton]

Bob, I don't do many roughouts, or bowls for that matter. But, when I do them I seal only the exterior and the rim and that permits drying from the inside. I have had excellent success doing that, but it does take a few months. I am curious what would happen in your kiln with that approach. On the next round of them, would you mind sealing one in that manner just to see whether it is more subject to crack and whether it dries any faster than your others?

[Bob Bergstrom]

To answer all three questions, a lot depends on species, wetness, and where the wood came from on the tree. Veneer quality logs result in few cracks. Reactionary wood or oak, crack much easier. The last batch I had 16 walnut from a nice straight log from 7" to 20" no cracks and turn like butter. Had oak with some wild grain it it cracked in a number of places.
John I've air dried probably 500 bowls over 40 years of turning and the only constant is some move, some crack and there is always some that come out great. So is nature. The oak bowls I posted last week were sealed, paper bag wrapped and put at the lowest level in the garage. Some cracked and some didn't. I believe your technique has merit. Very few crack on the inside. I have been wondering if I used 6" shrink wrap stretching it vertically over and across the opening and down and around bottom. This would leave the side grain open on the outside with openings on the inside close to the side grain for moisture to escape. In total the moisture on the endgain would escape internally or out the side grain. Using shreak wrap on the rim has certainly helped cut down on cracked rims on my large bowls. Two maple in the picture above will have the rims wrapped and the oak will have lawn bag paper wrapped around them.