Peeling at growth ring interface

[Wayne Spence]

I am turning some wet russian olive with large growth rings. I have turned 2 bowls from the same tree with crossgrain and no problems. This piece however is a spindle with the grain running parallel to the lathe axis. Layers keep chipping and peeling off at the interface. Only when the curvature increases near the center does the peeling stop. Is there any solution? If the wood dries considerably will it help the peeling?

 

[john lucas]

What tool are you using? I've had that problem with Willow and seems like it was a Palm of some sort. When I used the skew no matter how sharp it kept trying to peel up. I switched to a detail gouge and solved the problem.

 

[Mark Wollschlager]

It may be ring shake, a separation of the growth rings from each other.
In larger pieces it can be dangerous as a chunk may split off of rest and take flight.
Just a thought.

Mark.

 

[MichaelMouse]

Wind shake would have affected the faceplate turning too. It also generally telegraphs its presence with some discoloration in the area of separation. http://i35.photobucket.com/albums/d160/GoodOnesGone/HemlockShake.jpg

John did not say how he was using his shallow-flute gouge, but success would indicate he was taking a higher sharpness angle and not getting under the rising grain, as he was with the skew. Good approach when used on a lot of ring-porous woods. Plan B is to maintain the low sharpness angle, but increase the width of bevel contact. I use a square chisel, but a skew, held with the handle way down would come close. Keep the downward pressure on the trailing bevel so the leading won't plunge and peel.

 

[Rob Wallace]

I am turning some wet russian olive with large growth rings. I have turned 2 bowls from the same tree with crossgrain and no problems. This piece however is a spindle with the grain running parallel to the lathe axis. Layers keep chipping and peeling off at the interface. Only when the curvature increases near the center does the peeling stop. Is there any solution? If the wood dries considerably will it help the peeling?

Wayne:

In my experience, Russian olive (Elaeagnus angustifolia) is one of the worst woods available around here (mid-Iowa) to be effected by ring shake, which is what you are describing. I have literally pulled out sections of heartwood of Russian Olive by hand while bowl turning wood of this species. It is difficult, but not impossible, to manage mild situations of shake-caused dissociation of adjacent growth rings by adding glue when the cracks are discovered (I use thin or medium CA glue, but this sometimes results in the darkening of the glued areas relative to the unglued areas).

The severity of ring shake will also vary by position of the wood in the tree to some extent. Branches with excessive wind movement or ice loading would be far more prone to ring shake damage than would a piece of wood from a mature trunk of the same tree. The relationship of the presence of shake in your blanks likely has less to do with the turning orientation (faceplate vs. spindle) than does the source of the blank - where it was taken from the tree, and ultimately how much physical stress that part of the tree was subjected to throughout its life. I'm guessing your spindle blanks probably came from thinner stock from the branches, and your faceplate stock came from lower down on the tree.... (...am I close?)

Despite the shake problems, Russian Olive is a very attractive wood to turn. I have sold many pieces made from it, and never turn down a source of this wood when it is offered to me.

Rob Wallace

(And Mark..... I have launched a few Russian Olive fragments in the manner you describe. You are absolutely correct!)

 

[Gretch Flo]

Russian Olive

Wayne:
Despite the shake problems, Russian Olive is a very attractive wood to turn. I have sold many pieces made from it, and never turn down a source of this wood when it is offered to me.

Rob Wallace

Rob, I agree. I love Russion olive, esp if I can get the bumps and eyes in the piece. The wood I currently have was brought to me by a tree surgeon-said it was the biggest RO he had seen. I cut it up 2 years ago, and am guessing it was 22 inches in diameter. Some rot in the middle. I really love it when there is a thin black line (spalt) separating the wide annular rings. Gretch

 

[MichaelMouse]

As mentioned above, wind shake telegraphs its presence by a darker area. This isn't spalt, but additional extractives trapped out of the normal flow pattern. Sort of a super heartwood color. Similar to the darker color under a branch where the flow is disrupted.

Once again, to the OP, if you didn't have them in the other orientation, and they don't show at the ends of your long grain pieces, you're just pulling slivers. This is curable by technique, shakes take glue.