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My wife asked me what I was cooking for supper. I said a yummy bowl. Actually I have my own lawn sale microwave, an old one with settings down to barely warm. Was in town a few days ago and noticed some one had cut a decorative tree down. It was soon loaded in my truck, Not sure what it is but smells when cutting green and has a nice cream color, any ideas. I wanted to see how it finished up so tri.ed drying it in microwave. I put it in a brown paper bag and used a low setting, several hours later was ready for returning and finish, wipe on poly. Plan to give it to the lady this weekend. wonder if she will say, "It looks good enough to eat" after I tell her I cooked it. I worked on a piece with multiple branches last night, I think this one should go through a slower drying process and thinking of end log sealer. I have lots of time as will have to get to work on the other logs before they crack.
Has anyone had experience with microwave drying or it just impatient me? Thanks for looking.

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Nice piece of turning! Not sure what the wood is, but I sure like the end result you got.

I just about have SWMBO convinced that we need to replace the 18-year old microwave in our kitchen, so I will soon have a microwave in the garage. I have a bunch of logs from an ornamental pear tree my neighbor took down last year that I want to use for natural edge bowls and hollow forms.
 

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What you did with this would sure is attractive. Nice work. I have know idea of how to dry something with a microwave. Whatever you do don't blow yourself up.

helluvawreck aka Charles
http://woodworkingexpo.wordpress.com
 

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Good work.
The microwave has saved me many times. A friend brought me a large chunk of "wet" walnut he wanted turned into a bowl asap.It finished up as a 16" X 7" bowl. Roughed it out to about 1" thick and then cycled it through the microwave (alternating heating and cooling) until it was dry enough to finish. It warped out of round about 1/4" during the drying process but no cracks.
 

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very nice live edge bowl Brian… you did a nice turning job on it and nice finish too. Great job thanks for sharing..
 

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Very neat!

While in the microwave; you could have added popcorn!
 

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Nice job. I havent had much experience with microwave drying, but it looks like you have the process figured out. the wood looks like bradford pear to me. FWIW
 

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I use a weak microwave, like 600 watts. I just cook it for about 5 mins, get it steaming hot, then cool it for 5, for a few cycles, then down to 4 on and 4 off, and down to 1 minute. You can tell its cooked by the weight, or a moisture meter. Have seen some say just start with 1 minute, but I havent blown one up yet or had one crack.

Can take a while, so its nice to have one in the shop that you can babysit while you do something else.
 

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Nice turning and great use of an old MW. I guess many at curbside only need a fuse but people toss them thinking it is shot. The fuse is easily replaced and then you have a good MW.
 

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Very Nice Work!
 

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I use the microwave for most of my turnings. I use a pretty powerful microwave at full power following this process:

- Weigh piece on postal scale
- For each 10 grams of weight, microwave on full power for 1 second (e.g. 500g piece = 50 seconds). Use this amount of time for each successive microwaving (do not reduce time as the piece gets lighter).
- Leave out on an elevated cooling rack to cool - 5-15 minutes(I usually use the burner over the gas stove instead of a cooling rack, since I can never find the stupid thing).
- Weigh piece again and repeat microwaving cycles.
- Once the weight stops changing, it's dry.

Number of cycles depends upon lots of factors (species, initial moisture%, etc.) but usually 5-10 is about right. I typically turn 3 or 4 pieces during the day and them dry them all at night and finish the next day.

The above method is good for pieces from say 300-1000 grams. below that, I'd reduce it a bit and above it I increase it. Note that very small surface checks will frequently form, particularly on the end grain areas. These almost always close on their own. You must resist the urge to use CA glue to keep them from opening further - doing so will cause them to stay open!

The biggest problem I have with microwave drying is with live-edged pieces. The bark shrinks at a dramatically different rate and frequently separates from the wood. This can be partially mitigated by flooding the cambium layer with CA glue before the drying process starts.
 

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JamesVavra-Thanks for the thorough explanation … sounds like excellent advice.
 

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JamesVavara, that's interesting. maybe i am leaving my pieces too thick. I'm leaving them 3/4 to an 1' think to microwave, thinking that will dry them out without the warping. it does keep them from warping (or if they do, you have enough material to turn it out.

Maybe I'll turn to finish thickness and try nuking for less time.

Oh, and I didn't say it earlier, but that is a good looking live edge bowl you have made there. the finish looks just as good.
 

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I shoul clarify - almost all of mine are final thickness when I microwave. I like warped things.
 

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Techniques for microwaving seem to vary a bit. One addition one not mentioned is to put the blank in a brown paper shopping type bag folded closed during the heating process. Open the bag slightly during the cooling cycle. This acts like a "steam" kiln in that it retains some moisture on the surface of the wood while it is cooking out from the inside. This reduces the possibility of cracks developing.
 

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Brian, this is gorgeous.
Thanks to you all for the input on nuking, I'll be trying that.
Brain, did it go oval on you? I've turned some pieces and just left them out to see what would happen. For instance, a Peach bowl I turned while very wet, shaped itself wonderfully so while sitting outside on my woodpile for a week or two. I left it that - about 1" thick - because I didn't think I could improve on its own design. Incidentally, no cracks.
 
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