micro wave drying technique

[allen thunem]

Ok here is my dilemma
xmas is coming and i have over 50 roughed out bowls that is a conservative number. these bowls have been roughed out starting back in oct.
none are dry enough to finish turn. I need a few suggestions on how to speed up the process, i.e. micro wave drying, alcohol drying etc.
can anyone assist?
allen

[Cathy Schaewe]

I've used the microwave on a number of pieces recently for getting Christmas presents to the point where I can final turn them, and it's been very successful. Maple, cherry and walnut. There's an article in the most recent edition of Woodturning about it. I haven't followed those rules, though. They talk about putting it in a bag, and wrapping the edges with cling wrap, and they may turn the power down too, and they do it for a couple of minutes at a time, if I remember correctly. What I've done is put it in the microwave for 35 seconds at full power. Let it cool down completely. Do it again, and again, until it stops losing weight. I do it over the course of a couple of days. Then wait a couple of days. In all cases, the piece actually gained about an ounce after waiting. At that point, it's been completely dry and ready to turn. If there's a crack in the piece to start, though, I wouldn't do it. Never burned any wood this way. YMMV.

[allen thunem]

ymmv?????
im gonna give it a try
most of what im trying to dry is english elm and some cottonwood
and a bit of box elder
tanks cathy

[Cathy Schaewe]

ymmv?????
im gonna give it a try
most of what im trying to dry is english elm and some cottonwood
and a bit of box elder
tanks cathy

Sorry. "Your Mileage May Vary."

[dan carter]

You better make sure your better half is gone when you do the elm; I remember years ago I used the microwave in the teacher's lounge, he heh the principal was really steaming when she came down to the shop. My partner in crime did what all partners do, he took the hit for me; he was the first shop teacher she ran into, boy did I owe him. :-)

[Cecil Walborn]

I have used Microwave drying and worked good. I put a piece of wet box elder in for about one minute on high power then let cool down till cool and repeated it for four times then let it set for four days then finish it. It was good and dry when I finished it. One minute on high did not on this piece burn it any. It maybe a different time on other woods. Would watch and set time to each wood to be sure it does not burn. The also did not warp any so worked great on this piece.

[Bernie Weishapl]

I have used a microwave with some success. I use the defrost cycle and leave the high power for the last cycle or two. I also let them sit for a day or two after and before turning.

[Ron Stadler]

I read an article on drying wood in the Microwave that I found pretty interesting, this man told how he put his bowls in a sealed up zip lock bag, then stuck it in the microwave on High, when the bowl get hot enough steam will form and fill up the bag, when this happens its time to turn it off, now take it out of bag and let out the steam and let cool, oops almost forgot, make sure you record at what time it took to make it steam. Ok now that it cool again, place it back in the microwave but this time without the bag and to the time you recorded, keep doing this for 3 to 4 times on medium bowls and then stick it back in bag and make a new recording of time, the more it looses moisture the faster it is going to get hot and steam released filling up the bag. So now that you have the new time recorded use this without the bag again. All the time you are doing this I would weigh it also after each cooling period. You'll have to play around with this, because different wood and size of your bowl will play a major roll in drying, but I have had a lot of success with it and really like this method rather than just sticking it in the microwave and guessing when its hot enough, but just make sure you stop it as soon as the steam fills up the bag and make regular checks on the time ever so often, well hope this will help, good luck. Also you might think on getting a different microwave for your drying of bowls, some woods stink bad, red oak being one of the worst for me so far, smells like puke.

[Josh Bowman]

I can tell you this: If you leave sugar maple in the micowave too long the smoke from the charring wood, will make the whole house smell like a barbeque and the microwave from that day forward will smell the same everytime you use it.

I wouldn't have a clue why I know that

[Ralph Lindberg]

I've used both the 30 sec at full power, let cool, repeat and the 10 minute at defrost, let cool, repeat methods (hint weigh between cycles) and had excellent success.

The key is, do it slow and let it cool

I hunted Thrift stores and friends and have three old LARGE microwaves now. When one dies, I will just switch to the next one. I never will use SWMBO's kitchen one

Microwaving is not new, last winter I was going through some old paperwork and found an article from FWW on it, the article was 15 years old and I hadn't even planned on turning back then

[Bob Wolfe]

Here's a tip for someone who might use the "good kitchen" microwave for drying, burns the piece and stinks up the microwave something terrible. Remove the charred piece and either hide it in your shop or destroy it. Make sure there are no more charred bits of wood remaining. Fill a microwave safe container with 1-2 cups of white vinegar. Microwave the vinegar until it boils and then for an additional minute or so. Repeat the boil. While the microwave is still very warm, remove the vinegar and thoroughly wipe down the inside of the microwave with a damp cloth. If it smells like anything except for vinegar repeat the process.

If you're lucky you'll get a thank you for cleaning the microwave. I was left with a sparkling clean microwave and the only smell was vinegar which dissipated over the next couple of days. I hope this helps somebody out of a jam.

[Lee Koepke]

A word of caution regarding microwaving wood that I have read ..... since the wood heats from the inside, its possible that its charred where you cant see it, thus carrying the (probably slight) potential for continued ignition process.

The article recommended you never leave the wood unattended until its very cool .. and then I'd still be cautious where you put it for the next day, just to make sure !!!