Rough turning bowls

[Rusty Nesmith]

Been rough turning a lot of bowls lately. I don’t know why but I always stop a few times before I get finished to look at the progress and shape. This blank looked great when I put it on the lathe. This is what I found during my first stop to inspect. This could have gone very bad. After seeing this I will definitely keep up with the stopping to inspect.

 

[Marvin Jones]

Wow Rusty, worst case could have been really bad, best case would have been a wardrobe change for me if that came apart

 

[Chris Lawrence]

Its ring shake or wind shake. Its separation of the grain. It happens when a tree takes damage from bad wind storms or while getting cut down when it hits the ground. If you have other blanks from the same tree they may all have it.

 

[Don Wattenhofer]

The way the grain pattern on either side of the shake doesn't match and the dark color in the shake seams to indicate that it was there when the tree was much smaller. What species?

 

[William Rogers]

I have run across ring shake, mostly in walnut. Good time to quit when you see it.

This piece I didn’t expect what happened. I was roughing out an urn today. Wet walnut and saw what I think was some insect activity at one end. My intentions was to cut off that end, but before I got to that point this happened. It did not fully separate and fly off. Was turning about 600 RPM. Pry bar show it almost fully separated. The two dark lines are similar to the one that split. I was surprised to say the least.

 

[Richard Coers]

That can also be caused by a lightning strike. Especially when you see unusual colors like green. That's usually caused by an bacterial infection from the lightning damage.

 

[Leo Van Der Loo]

Biggest problem it seems is trying to dry whole logs, rather than turning green wood and let it dry after .

 

[Don Wattenhofer]

I have run across ring shake, mostly in walnut. Good time to quit when you see it.

This piece I didn’t expect what happened. I was roughing out an urn today. Wet walnut and saw what I think was some insect activity at one end. My intentions was to cut off that end, but before I got to that point this happened. It did not fully separate and fly off. Was turning about 600 RPM. Pry bar show it almost fully separated. The two dark lines are similar to the one that split. I was surprised to say the least.

View attachment 44403

Ring shake follows the annual rings as in Rusty's picture where as your crack crosses the annual rings and there are 2 other cracks visible so Richards explanation is more likely.

 

[Dave Fritz]

Always a good idea to stop and inspect. You may want to readjust the blank to get a better grain orientation or for some esthetic reason.

 

[Randy Anderson]

I sometimes wonder if I stop too often in my roughing out process but good reminder that it's still a good idea. I'll turn for a minute or so, stop to check for cracks or knots or other defects that were not obvious initially, then move on if ok.

 

[robo hippy]

After all the years of turning bowls I have behind me, I am getting much better at identifying problem pieces before I put them on the lathe. Not perfect by any means, but much better. I do like to check a few times as I turn, mostly on the outside of the bowl. Once I get to the inside, things should be fine, but I still 'listen' for different noises as I turn.

robo hippy

 

[Rusty Nesmith]

The way the grain pattern on either side of the shake doesn't match and the dark color in the shake seams to indicate that it was there when the tree was much smaller. What species?

Maple

 

[Dean Center]

Its ring shake or wind shake. Its separation of the grain. It happens when a tree takes damage from bad wind storms or while getting cut down when it hits the ground. If you have other blanks from the same tree they may all have it.

Current expert thinking is that an infection is the main cause, contrary to prior understanding.