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Discussion Starter #1
My area has a lot of fallen trees from Hurricane Sandy. I'd like to turn some of this stuff green. I've only turned dried wood.

So, a question. I hear I should rough turn the bowl to 10-15% wall thickness and let it dry for months before finish turning it. My normal method is to use a faceplate screwed into the wood and to shape the outside of the bowl. I cut a foot for my Vicmarc chuck and flip the piece around to hollow out the inside before final sanding and finishing. What worried me with turning green blanks is that after drying the foot will be distorted and not stable enough to hold the bowl solidly. Or, the thing will be out of kilter and will vibrate.

Am I worrying too much?
 

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My area has a lot of fallen trees from Hurricane Sandy. I'd like to turn some of this stuff green. I've only turned dried wood.

So, a question. I hear I should rough turn the bowl to 10-15% wall thickness and let it dry for months before finish turning it. My normal method is to use a faceplate screwed into the wood and to shape the outside of the bowl. I cut a foot for my Vicmarc chuck and flip the piece around to hollow out the inside before final sanding and finishing. What worried me with turning green blanks is that after drying the foot will be distorted and not stable enough to hold the bowl solidly. Or, the thing will be out of kilter and will vibrate.

Am I worrying too much?
It's a valid concern.

Normally I put the dried bowl over a chucked lump of wood (friction drive) and bring the tailstock up tight with the point of the live center in the hole still there from the first turning. Then very gently scrape the foot till it's round again, and (just as important) there's a square shoulder for the jaws of the chuck to butt against.
 

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I was at a bowl turning demo back in the spring. The demonstrator introduced me to a term I had not heard before "shake".

If the tree merely fell down, it can be used for turning. If the tree was literally shaken by the violent winds, you may want to pass on this.

The demonstrator mentioned that if a tree experienced "shake", it may be unstable during turning and fly apart.

Apparently the violent to and fro from the wind can cause the internal structure of the cells to break down.

I have no idea how to tell whether a tree had "shake". I hope others can advise.
 

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I do as duncsuss does. If it is green make your tenon about 3/8 larger than your jaws. This will give you enough wood to re-true your tenon and still be able to grip with your chuck. 1+ on making sure you leave a divot from the tailstock to re-center. I normally reform the tenon and about 2” up the side of the bowl before chucking and reversing.
 

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First I try too turn the whole bowl to 10% thickness. This includes the bottom plus tenon. The bottom won't move as much so you can leave it this thin and not have a problem with reshaping.
When you turn the bowl with it in the tenon you can make yourself a center mark so mounting it later will be easier. I turn a wooden plug that just barely fits inside the threads of my chuck. I center drill this 3/8". When I'm finished roughing out my bowl I remove the chuck and bowl and insert a 3/8" brad point bit in the hole of my wooden plug. This makes a center mark in the tenon of the bowl.
Now when my bowl is ready to put back on the lathe what I do is put a rubber sink stopper over my chuck and put the open end of the bowl over the chuck. I bring the tailstock up and put the center point in the mark left by the drill bit. This centers up the bowl as best it can get. Then I turn the lathe on fairly slow and true up the tenon. You can if your comfortable with this, turn the outside of the bowl now as well. Often it will shift slightly when you mount it in the chuck. Sometimes I true up the outside and sometimes I don't worry about it.
Hope that makes sense.
 

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Thinking too hard, turned tons of green bowls, first of "shake" doesn't exist.. And the general rule is turn it about 1"-1 1/2" wall thickness and let it dry for months, microwave on defrost works great, look into it, but ya lets why you let the walls stay thick so you can still return it when it dries, some woods warp more then others but you'll be fine good sir
 

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Ring shake does exist. When a tree flexes in bad wind or sometimes when it's felled it it will crack internally usually along the growth rings. You can't see this and I've had bowl blanks that look perfect until you get into the inside and find a ring shake that's just waiting to explode the bowl.
Not all trees have this but if I have a storm damaged tree I am much more cautious. I have discovered this in downed trees but really didn't see it bad until all of my Bradford pear and one maple were torn down in a storm about 3 years ago. Naturally I cut up the wood to save some for turning. After roughing about 5 or 6 bowls from different parts of the trees and seeing ring shake in everyone I cut the rest of it up into box and spindle blanks. It's amazing how much ring shake I discovered when I did that.
 

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Shake is made up term.. Yea when a trees falls it cracks..separating the annual rings, just a term wood turners made up, it's called damaged
 

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Ibangwood said:
Shake is made up term.. Yea when a trees falls it cracks..separating the annual rings, just a term wood turners made up, it's called damaged
Not true. Ring shake is when the annual rings separate.

image-3367565521.jpg
 

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Discussion Starter #10
Well, I guess I got my answer, sort of. Now, I'm not sure I should be turning any of this wood if it has a chance of exploding while turning. :eek:
 

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Just cut off some sections into little pieces and see. The best thing is to stand out of the line of fire, which is the direction you think it might follow if it comes apart. WEAR A FACESHIELD, and start off turning slow until you see how it develops.
The best thing is to not use the wood right near a break. If you can go several feet up. If it's a tree that's been pushed over it may be alright. some trees are worse at ring shake than others. I saw it as I was cutting it up on my trees so I was leary of it before I started. The Ash tree that blew over in the front yard didn't have any that I could find.
 

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Discussion Starter #12
Sandy score!

Okay, I was helping my cousin chainsaw some trees yesterday that came down in Hurricane Sandy and I was able to get 4 logs for green turning. I used a log splitter to create 8 bowl blanks. I think the wood is ash or maple, but I'm not sure. Hopefully, it's not oak.

When I got them home, I painted on interior/exterior primer to the end grain to slow any checking and put them in my basement shop. This morning I decided to try green turning one.

Some observations:
1. The blanks needs to be pretty close to round otherwise the shaking is extreme. I kept going back to the bandsaw and cutting more to get it more balanced.
2. The wood is WET. I got quite the shower. :thumbsup:
3. The shavings really flew! I think some landed 15 feet behind me. Nice long spaghetti strings! I standed out of the line of fire the entire time. No incidents occurred.
4. Like I said, the wood is wet. My lathe bed and roughing gouge started rusting before I finished rough turning the wood. My planer behind me got wet enough that I had to stop and spray some WD-40 on the iron bed to stop the rusting.
5. I turned the walls to about 3/4" - 1" for the 9" bowl blank.
6. I placed the rough turning in a plastic bag with some paper towels. I read this on some other website. Is this enough or should I used newspaper or paper bags? I've seen all these tips recommended.
 

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I placed the rough turning in a plastic bag with some paper towels. I read this on some other website. Is this enough or should I used newspaper or paper bags? I've seen all these tips recommended.
I would not use plastic. You will rapidly get a mold growth.

I placed a wafer from a newly cut limb in a Ziplock bag just as an experiment and within a day I had this white mold.

I would use paper bags. I read to use the paper bag upside down, so the "bottom" of the bag up and the open end of the bag down. This allows moisture to gradually dry out and is meant to slow down the drying process to minimize cracking.
 

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Yea i got wood
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you know here we say it didnt happen unless you have pics to prove it:laughing::laughing::laughing::laughing:
pics we need pics:yes::yes::yes::yes:
 

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Discussion Starter #15
pics

Okay, I took the bowl out of the plastic and now have a paper bag placed over the top. Is that all I do? Can I place more than one bowl under the bag. Or, would that cause uneven drying?

Here's some pics. The bowl is atop my logs that were coated with primer/sealer. Maybe, someone can tell me the species of this wood?
 

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My understanding is the plan is simply to reduce airflow around the bowls to a minimum, allowing the wood moisture content to very slowly adjust to equilibrium with the room it's in. Multiple rough-turned bowls in the same bag shouldn't cause a problem.

The piece of tree trunk in that photo looks like a type of birch -- I don't know all the different types. Paper birch has distinctive bark that peels off in thin paper-like layers.
 

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when i first started turning i ask the same thing and alot of people suggested putting my green bowls in a brown paper bag and put them up in a cabinet for a few months.this has always kept mine from cracking
 

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Great idea. These kinds of natural disasters are terrible but making some good out of it just seems like the right thing to do. Many historic turn of the century houses in small hill country communities in central Texas are made from flood fall cypress. Huge flood wiped out alot and people got to milling!
 

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Discussion Starter #20
A few of my split logs that I sealed with primer/sealer have some end checks in them already. I suspect that by the time I order Anchorseal it will be too late to apply. Do I need another coat? Should I cover them with latex paint or paraffin wax? Mix 50% mineral spirits and 50% paraffin wax and brush on?

Or, is this type of thing expected? IOW, is end checking inevitable?

Nate Bos, I used poplar lumber in the past and it always had a greenish cast to it. So, I'm thinking it's not poplar.

TIA.
 
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