[OP]
Contributor
Hi, I have drying question. I rough turned a green maple bowl blank and placed it in a trash can full of shavings then placed the whole thing in our small green house which was about 3 weeks ago. The blank weighed 3.02KG when I first placed in the shavings. I just weighed it again today and it is down to 2.82KG. I'm sure it needs to dry for a while longed so what kind of weigh am I looking at before I finish turning it. Thanks, Jim
Contributor
It would be difficult to give you a dry weight as there are many variables with wood. You will know it is dry when it stops losing weight.
Contributor
Ditto Robert - when the weight stabilizes.
Contributor
I don’t have a lot of experience twice-turning but have heard some say it takes about 9-12 months per inch of thickness, but that would likely be sped up in a greenhouse. I would just continue to weigh it every couple weeks until it stabilizes.
Tom
Contributor
That is way too general of a rule because walnut or ash will dry twice as fast as white oak or apple. If the shavings have any spalt on them, you get an excellent chance of mold forming on the bowl. I put my wet bowls in yard waste bags and chance the bags everyday at the start of the drying.Originally Posted by Thomas Wilson80
Friend of the Creek
Wet shavings and a warm environment with maple are the perfect set up for grey mold...Drying is a topic that would fill a book.
For fast drying I am currently trying one of the desiccant beads...using wt loss of 30% or more. This takes about a week. This is also a learning process. Each turner has their own way, depending on their geographic location, the air handling in their ship and wood species.
Contributor
I think the year/inch rule has been debunked at least for bowls, may have some benefit in stickered long boards but I don't know. Half a typical turned bowl is end-grain and that's where the moisture loss is fastest - a lot different than a long board for the fast drying area . Don pins it down in his last sentence concerning environment and wood species. The drying rate would be a lot different in Arizona than it would be in Seattle unless it was in conditioned air space. Water is what is loss when drying and the best way to know it is gone is by weighing - absolute numbers useless but when it doesn't change anymore then the water that can be lost is now done.
I have stopped the surround it with shavings method. When the bowls are real wet it is a mold promoting environment. I turn a fair bit of maple at times and it loves to mold quickly probably because of the sugar-content. I use yard bags or wrap in newspaper and put in a box. In the first couple of weeks or so, I try (I'm not perfect) to check it daily and if the paper is wet which it will be at first, I change it. IMO, black mold in maple is not attractive so I try to avoid it.
To minimize cracking I put Anchor-seal only on the outside surface of the exposed end-grain. This inhibits the drying speed but still allows drying.
Last edited by Bill Howatt; 05-15-2023 at 9:40 AM.
Contributor
I use the weigh it every once in a while until it stops losing weight method. I stopped putting bowls in shavings because of mold issues. I do apply anchor-seal if it is a species that cracks easily or an especially nice blank that I don't want to chance losing. My suggestion is to rough out lots of bowls at a constant rate so that after the first is drier than necessary you have a constant source of ready to finish bowls. Nothing wrong with having many projects waiting for you.
Member
Dry shavings are better. Maple has a lot of sugar in it, and dampness will make it moldy, which is not a good thing. You can put it in a dry paper bag, and put that inside a plastic bag. Change out the paper bag daily until it pretty much stops losing weight.
robo hippy
Contributor
Your post brought back an old memory from when I started turning. Experienced turner told me about roughing, waiting months to dry, then finish turning. I thought about waiting for the wood to dry and was very disappointed to hear that news. Of course, the reality is I always seem to have a lot of bowls waiting for me, not me waiting for them.
Contributor
Excellent advice. When I first started turning bowls the wait time for the rough to dry was agonizing. Then the light came on and I contacted a couple tree service companies. I soon had to cry uncle, I have enough. Tree companies in this area are happy to give you wood as it saves them tip fees at the disposal sites.
Currently I have enough dry rough blanks in several species that I will probably never get to all of them. I can picture the day my heirs are all standing around asking each other "Wat the h... do you suppose he was going to do with all these?".
[OP]
Contributor
What are desiccant beads? Are we talking something like kitty litter or something different? Jim
Contributor
Desiccant is reusable, kitty litter is not, usually just clay.
Google, desiccant or silica gel
Some actually changes color when it's wet, which might help
Contributor
Great information on here. I just started twice-turning bowls last fall so I will need to start checking and weighing them sooner than I thought.
thanks, Tom
Contributor
"I can picture the day my heirs are all standing around asking each other "Wat the h... do you suppose he was going to do with all these?".
I bet this is going to be a common thought on this thread. I know I have more wood sitting around than I will ever get to.
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