Using a food dehydrator to dry green wood turned bowls

[Reiner Jakel]

I hope I am doing this right, new to this site. Before joining I by chance saw a discussion about using a food dehydrator to dry green turned bowls. I want to share what I have done in this regard. I was surfing You Tube and ran across a video by the Wood Whirler who was using this method. Bing impatient and not one to wait years or months I dove right in and ordered a food dehydrator on Amazon. I have turned 10 fairly large wet bowls. I finish turn them including using a couple of coats of sanding sealer before placing them into the dehydrator. As there is no instruction manual on how do this I experimented with the temp. and time. Most I put in at 131 degrees and left them in there for between 40 and 70 hours. I just did a walnut bowl for twice turning and had it at 101 degrees for 50 hours. It is guess work on figuring out how long to dry them as the pin moisture meter only reads at the depth you insert the pins to. I get no readings when I first take them out . I take them into the house and after a few days I get a reading of around 12 percent.
I did use an electronic moisture meter on my last few but find it difficult to get an accurate reading as the surface of the device is flat and the bowl is round. I continue to try different methods and alter my approach. The GREAT thing is that I have not gotten any cracking at all in any of my 10 bowls.
I gave a presentation to my group, Southern Utah Wood Turners , today and it sparked a lot of interest. I am hoping to reach turners that may have experience with this and are willing to share tips with me Thanks for listening. Reiner

[Ken Fitzgerald]

Reiner, welcome to the Creek!

I have no experience with this method of drying rough turned bowls so I can't comment but will follow it with interest.

You mentioned you were in Southern Utah. Where? As a child I lived in Blanding for 1 year and attended 5th grade there.

Again, Welcome to the Creek!

[Wally Crawford]

I have no experience with a food dehydrator for drying bowls, but I have a drying cabinet that I made out of an old fridge that works well. I use incandescent bulbs as a heat source and try to maintain 100*. I use a food scale that measures in grams to weigh the bowls and when they quit losing weight, I know they are dry. I then let them sit for a week to acclimate before finish turning them. Depending on species and green moisture content, it can take from 1-3 months.

[Reiner Jakel]

Reiner, welcome to the Creek!

I have no experience with this method of drying rough turned bowls so I can't comment but will follow it with interest.

You mentioned you were in Southern Utah. Where? As a child I lived in Blanding for 1 year and attended 5th grade there.

Again, Welcome to the Creek!
I am in Cedar City Utah and thanks for the kind words.

[Reiner Jakel]

Yes, I have seen a number of videos on using a chest freezer to make the kiln. Something I probably will do in the future. I do however like the fact that the dehydrator only takes a couple of days

[Reiner Jakel]

Yes that seems to be a very solid method for drying. Something I will most likely do in the future. For now I would like to continue on my path of using the dehydrator and test it enough to be able to paisss along reliable instructions on its use. Not there yet but great results so far. How do I post pictures on this site.

[Russell Neyman]

I'm open to new technologies, but here's my basic approach to curing wood for turning:

The issue is not -- and never has been -- to DRY the wood; it's to dry it without CRACKING. All wood shrinks as it loses water, but it mostly loses moisture in in the direction of the grain. That means one part of your hunk of wood is shrinking faster than another, and stress causes cracks. Speeding up the drying process simply speeds up the cracking process, too. Now, rough-turning a bowl and then using a mechanical process of drying it out quicker might work, but the wood will still shrink as it dries. There's no way to get around that. Keep us posted on how this works out and take lots of pictures of each step along the way.

[Brian Tymchak]

Interesting. Thanks for the post and welcome to the Creek! I would have guessed that 100°+ temps would dry the bowls too quickly and end up cracking.

[Sam Force]

How do I post pictures on this site.[/QUOTE]

You have to be a contributor to post pictures. $6 per year, look under the "donate" link in the tool bar

[Tim Elett]

How big is the dehydrator? I'm thinking bowl size would be limited, welcome to the site.

[Reiner Jakel]

Thank you. Reiner

[Reiner Jakel]

I will continue my efforts and post them. Thanks Reiner

[Reiner Jakel]

Actually, most of my finished turned bowls ran at 131 degrees for between 40 and 70 hours. None of them cracked but two did warp a bit. On a 10 inch bowl the diameter changed 1/2 inT measuring from the end grain diameter. The others had no cracks at all. The ruff turned bowl for twice turning I ran at 100 degrees because I figured it had a bigger chance of cracking. Just one small crack by a knot appeared. After I brought it into the house for a few days the small crack got smaller. Going to final turn it today. Reiner

[Reiner Jakel]

The one I purchased from Amazon was around a 100 dollars and the inside measurements are aprox. 13deep, 12 wide and 10 inches high. So far it has been large enough for all my turnings. Much larger ones are available. Reiner

[Tim Elett]

The one I purchased from Amazon was around a 100 dollars and the inside measurements are aprox. 13deep, 12 wide and 10 inches high. So far it has been large enough for all my turnings. Much larger ones are available. Reiner
Ok, That's much bigger, taller than ours..

[Brice Rogers]

I built my own food dehydrator. Where the screens go, internally it is roughly 12" x 20" x 10". I use an incandescent bulb for heat and a computer fan for circulation/ventilation. To keep bugs out and to filter the air I used an air filter from an automobile. It works great for dehydrating fruit. I've never used it for drying green wood, but I've used it to speed up curing polyurethane finishes.

I'd encourage anyone interested in using a dehydrator for green wood to just build their own. They are incredibly easy to make.

[Reiner Jakel]

Sounds good. What you describe sounds like a wood kiln. Not sure what the difference is between that and a dehydrator but I will dig into what if anything is different with the dehydrator. Thanks for the response. Reiner