maximum temperature on drying rack

[MICHAEL GOLD]

Hi,... I'm new at this. Turned a dozen green 1/2" thick tanoak bowls.....microwaved them till weight stabilized....no checking/cracking.....built a storage/drying overhead rack for final drying....max.temp. gets to high 80's - low 90's......anyone know if that's o.k. or is it too hot?....... Thank you for any input.............michael

 

[Bill Boehme]

Hi,... I'm new at this. Turned a dozen green 1/2" thick tanoak bowls.....microwaved them till weight stabilized....no checking/cracking.....built a storage/drying overhead rack for final drying....max.temp. gets to high 80's - low 90's......anyone know if that's o.k.? Thank you for any input.............michael

Well, it depends. You didn't say what diameter or if they were rough turned or finish turned or what. If you rough turned the bowls to a half inch , that is rather thin unless the bowls are very small diameter or it is a species of wood that doesn't warp much.

It is counterproductive to microwave dry and then air dry the bowls especially where it seems like you are storing them in a rather hot location unbagged and uncoated with sealer. The objective is to mitigate cracking by slowly drying the pieces. As far as I know, microwave drying is generally used for drying a piece that has been final turned and where the resulting warping will be part of the final intended design. You might be fortunate if the bowls are small and not have any cracking, but it seems to me that your procedure might be more likely to cause cracking than preventing it.

There are a number of methods for drying to minimize cracking ... you can't do much if anything about warping. These include sealing with Anchorseal or equivalent product and storing in a relatively cool location out of sunlight, bagging to slow down the rate of moisture loss and storing in same type of environment, and other similar methods. Some production turners have constructed drying enclosures that start off as heated high humidity environments that gradually decrease the humidity at a controlled rate. Unless you intend to crank out a large number of bowls o n a continuous basis, this wouldn't be the way to go.

My preference is to just coat green rough turned wood with Anchorseal and then let it dry in the air conditioned shop or in the garage which is also air conditioned for about 4 to 6 months depending on its size. Another thing that I frequently do is turn green wood to a thin final thickness of ¼ inch or less and it will be dry by the time that I finish turning. I am not familiar with tanoak so I can't help you there, but this area has lots of post oak which is a white oak and the green wood just loves to split. Live oak is much better behaved, but has to be turned green -- otherwise it is like turning iron.

 

[MICHAEL GOLD]

Bill, thanks for the feedback....the tanoak bowls average 6" high x 12" diam & 8" high x 10" diam.they are hawaiian calabash form purposely kept 1/2" thick ....finish-turned green in one go...wanting controlled warpage and raised figure...microwaved till weight stabilizes(pretty dry/no cracking/checking).....for final drying pre-finishing and storing built an overhead rack.......just wanting input of storing on a rack that gets in the 80's during summer ....thanks again for any input.........michael

 

[Bill Boehme]

OK, that sounds good. I misunderstood what you were trying to do.

 

[hockenbery]

Bill, thanks for the feedback....the tanoak bowls average 6" high x 12" diam & 8" high x 10" diam.they are hawaiian calabash form purposely kept 1/2" thick ....finish-turned green in one go...wanting controlled warpage and raised figure...microwaved till weight stabilizes(pretty dry/no cracking/checking).....for final drying pre-finishing and storing built an overhead rack.......just wanting input of storing on a rack that gets in the 80's during summer ....thanks again for any input.........michael

Michael,

If you dried them to weight stabilized in the microwave. You can store them just about anywhere except for a very damp environment

They are not going to dry anymore. And not going to warp anymore and should be ready to be finished when you are ready to do it..
A nice calabash curve with an even wall thickness at 1/2" is most unlikely to crack since the wood can move as it dries.

The main deal in successfully drying bowls and hollow forms is flowing curves and even wall thickness. With flowing curve being more important.

Have fun,
Al

 

[MICHAEL GOLD]

thank you, Al.........mchael

 

[MICHAEL GOLD]

OK, that sounds good. I misunderstood what you were trying to do.

thank you, Bill......michael

 

[robo hippy]

After they came out of the microwave, I would have let them adjust for a day or so in cooler temps, which to me is in the 70 degree range, then sand and finish. No more drying needed.

robo hippy