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William McAloney
11-23-2019, 9:24 AM
Hello all,
I've acquired a large stock of cherry and am now experimenting with drying roughed-out bowls, mostly 12" dia x 4" thick, and some a little larger. I'm turning to 10% wall thickness. The microwave method, using techniques described by others on this forum, has produced mixed results. I've been considering the kiln method, but wonder if it is effective in an unheated shop in winter. I have a space heater to keep the shop warm enough to work in during the day (45*F), but overnight the temperature drops to the outdoor ambient. The shop temp will fluctuate by 40 to 60 degrees daily.
Will a well-insulated kiln(I'm thinking junk dishwasher) resist the temperature swings? Should I use somewhat greater wattage bulbs in this season? Should vent holes be downsized? Should I just stick with microwaving until spring returns?
Others of you must have encountered this. I'd like to hear your methods and suggestions.

Bill in Maine

Steve Eure
11-23-2019, 9:58 AM
I have used an old dishwasher to dry blanks with mixed results. I used a 75 watt bulb normally, but when temps were low, switched to a 100 watt. I was getting around 90% success this way. As far as cold temps, I can't help much. I live in the lower SE where it rarely gets to freezing. I do use the bag and box method with wet shavings to dry. That method takes a little longer, but the results are better for me.

Peter Blair
11-23-2019, 10:02 AM
I'm no expert but I have not had much luck with thicker pieces in my freezer kiln. Now I only dry thin turned to finish pieces and I have about a 95% success rate. Here's a day by day reduction in weight on this piece of Maple. It was turned about 3/16" thick but I leave a bit of a base to rechuck. Sometimes cracks will occur in the thicker bottom that is in the chuck which then migrate up into the base so I usually use a thin parting tool to cut a channel next to the bottom. If anyone needs more information I could provide more photos.
420134

Kyle Iwamoto
11-25-2019, 1:25 PM
I'm not sure how a dishwasher compares to a fridge/freezer as far as thermal insulation, but I would think the inside will fluctuate as the temperatures do, but much much less. Give it a try. I like my freezer kiln. My temperature swings are much less than yours though. You may need bigger wattage bulb(s) and/or a thermostat controlled heater. Got a beer fridge in the shop? If you beers don't freeze I would assume the insulation is good enough. Not that I support drinking and working, which I personally never do.

Peter Blair
11-26-2019, 9:23 AM
Kyle, if you referring to my post those are the weights in grams recorded daily till it stopped loosing weight.

Alex Zeller
11-27-2019, 8:50 PM
I've had much better luck with the microwave method by starting off using the wood shavings method. I use one of the cheap moisture meters and when the moisture gets to about 25% I then try to finish it off in the microwave. I'm now leaving the wood in log form (usually 8') and letting it sit for a year or two. The moisture ferments and seams to come out of the wood with less damage. If I time it right I get the added advantage of fungus staining the wood.