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Hello all.

So, I've only been turning for a few months. Sometime (late November, I think), I picked up a bundle of 4 bowl blanks from Woodcraft on sale with the intention of turning my first bowls.

I got some easy wood tools for Christmas and so two days ago I set about turning. I "rough turned" the bowl. That is to say I ran out of shop time and had to leave. I went back this morning and wow... cracks galore. So, am I to assume that the wood that Woodcraft sold was still fairly green? I don't think they advertised it as kiln dried or anything, I'm not going to be asking for a refund or anything... I'm just looking to find out what went wrong.

The wood blanks were waxed when I got them. They were 6x6x2ish.

Any tips or tricks for a newbie. Should I have just held onto them for a year until they stabilized to my basement moisture?

Below is a pic.

 

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Wax sealed blanks are almost certainly not dry. One trick I learned is if you're going to leave a bowl, even for a few minutes, on the lathe then wrap it in a plastic bag.
 

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Wax usually means sealed in moisture to me. When I get blanks that have wax on them I trim some of the wax off to let it dry. Did you notice a fair amount of moist shavings coming off or maybe sticking to the end of your tool? I have a moisture meter that is pretty accurate but every now and then some exotic wood seems to fool it and I go to turn it and I can feel the moisture. I just take it off the lathe and reseal the ends
 

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Well, that sucks. I also have a waxed blank the same size of Osage Orange that I bought from Woodcraft, destined to be my first real bowl. Guess I'll scrape the wax off and see what happens...

Bummer.
 

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Wax sealed blanks are almost certainly not dry. One trick I learned is if you're going to leave a bowl, even for a few minutes, on the lathe then wrap it in a plastic bag.
Question then. Let us say I turn some, wrap it in plastic, turn some, wrap, turn and finish. Won't it still check and crack? It'll just wait until I'm done, right?
 

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If the wood is not at equilibrium with the moisture content of the shop then it will "move" meaning change dimension.

If you are lucky, it will just warp. If not so lucky it will warp and crack.

You do not want to turn to final dimension/shape until the wood is close to the shop moisture content.

Best way to know is by weighing each week and noting the weight. It takes some time for the moisture to equilize.

Keep the top lip round. A sharp corner will tend to crack.

Keep the sides same thickness or thicker than the bottom to try and minimize cracking.
 

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What they said. Turn it thick in order to allow it to dry quicker. Then u have to slow down the drying of the now thinner blank. I usually seal the end grain of the bowl with anchor seal. Then I place them in plastic bags. I write the date on the bag with a sharpie. Then I store it in a closet for a few months to a year. After it's dry I can remount it and turn to final dimensions. I know this can be a bummer for someone wanting to turn a bowl right now. U can practice with green wood turned thin. This will give you both the turning experience, and the opportunity to watch how wood moves as it dries. Use free wood from the neighborhood for this, not the expensive (anything not free is expensive to me) blanks from the wood store. Hope this helps.
 

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I'm not a turner, but I'm pretty sure you can place green freshly turned wood in a bucket of sawdust for awhile (couple months?) to minimize the warping/cracking as it dries.
 

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Waiting for a rough turned bowl to dry is painful when you are just beginning. Turning green wood to finished thickness has drawbacks but it absolutely can be done. Almost all of my bowls are turned green. Yes they warp but that may not bother you at all. In fact I'm a fan of oval bowls if done correctly.

If you try turning it to final thickness it is important to end up with a uniform thickness and 3/8" or less will minimize chances of cracking. It can be tempting to leave a thick foot but that will invite cracks. As mentioned earlier, firewood is a great place to start and can be just as pretty as a $20 blank. Once you get a few bowls sitting around the house then start roughing some and eventually you'll have a stack ready to finish turn and they'll stay round for you.
 

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Cover the unfinished bowl in plastic for a short period of time is OK while it's on the lathe. However, I would not recommend storing the rough turned blank in plastic. You want it to dry slowly and not seal the moist air in a plastic bag. The best thing to do is put it in a box, paper bag or in a closet.
Tom
 

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I am not a professional turner or a long experienced turner, but I've had good luck using a plastic bag. It does take time, but turn the bowl over size, put in plastic bag for a day or 2. take it out for a couple hours then put it back in the bag. Repeat and maybe turn it a little more but then back in the bag. Repeat as necessary. As its out of the bag, it releases moister, putting it back in the bag will equilize the internal moister becoming drier over time.
 

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+1 with TomC. I prefer the paper bag if not left in the open.

A plastic bag, especially if closed, could cause mold. Easy to turn off, but then mold spores in the air and perhaps in the lungs.

The paper bag allows the contents to breathe while controlling air movement.
 

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To me, if you are looking for the best way to dry a green turned bowl, turn it to within ten percent of the thickness you want. Place it into a paper bag along with some of the shavings, making sure turning is surrounded with shavings. Close the bag, weigh it and set it aside. Write the weight on the side of the bag with the date. Weigh it in a couple months, and periodically after that. When it stops losing weight it is dry enough. No need to mess with taking it out of the bag for a couple hours and re-rapping. It may be hard at first to grasp the fact you aren't completing anything but in a few months of doing this you'll have plenty of stock to complete
 

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I guess I am very fortunate to be a tree guy with more good wood than I could possibly turn. You should look up a few tree companies and ask them if they have any wood you could have. I give anyone asking for wood all they want. Start rough turning green wood, label the type, and date, toss it in a closet or garage cabinet and forget about it for a year. Just keep turning as many green bowls as you can. You get great practice roughing and before you know it you have 50 or more bowls ready to finish turned. And if a few crack just throw them away. I don't even seal them, if they are fresh and don't have any checking the usually never crack. ( Have fun and keep on turning. )
 

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After using a plastic bag I agree the paper does sound easier. One thing I have noticed is there is much less cracking and warping if you have straight grain. Knots are pretty but they won't shrink much when drying and cause problems.
 

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In my opinion and experience plastic bags cause mold and adding shavings to a paper sack doesn't do anything but can cause mold as well.
I use a plastic bag anytime I'm turning and have to stop for some reason. I even plastic bag it if I stop to go to the bathroom. Cracks start all to easily when it's first turned.
When I have it roughed out I place it in a paper sack. No shavings needed. The paper sack stops the air movement and direct light which is what causes the bowl to crack. Well actually what caused the bowl to crack is the outside drying faster than the inside. when wood dries it shinks. If the outside shrinks and the inside doesn't well you know what happens. By bagging the blank you stop the air movement which equalizes the drying inside and out.
It depends a great deal on your environment of course. I can often put roughed out blanks on the floor in my shop and not do anything else to them and they will dry OK.
If you have a waxed blank and want it to dry a little don't scrape the wax off the end grain. The end grain areas dry faster and it will crack if you scrape all the wax off. It's very hard to actually dry a bowl blank so I never worry about the wax. I just put it on the lathe and rough turn it and put it up to dry.
Want to turn a green bowl to finish. If you turn a bowl to 3/8" or less, and I mean everywhere, don't leave a thick bottom or large foot. You want it to dry evenly and it will do that much better if it's the same thickness. Once you've finished it put it in a bag for a few days and it should be fine. Thinner is better but 3/8 works pretty well. If you leave it 1/2" thick just leave it in the bag until it stops losing weight. A 3/8" thick bowl will dry in about 3 or 4 days. Thenn you can sand the bottom flat so it sits correctly. I turned a walnut limb natural edge bowl for a demo on Saturday. Put it in my car to take it home and left it in the trunk Sunday (it was about 35 outside). Picked it up today and it's not dry but not far from it. I'll finish sanding it this afternoon and it will probably be dry tomorrow.
 
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