disaster and salvage

[Mark Pruitt]

This happened yesterday. Piece of pine, been lying around a long time building character before I came across it and put the chainsaw to it. I turned a NE from the same log two weeks ago, and figured I'd do something different. I roughed out the outside and inside, and was ready to refine the inside surface with a bowl scraper. Bad move! The split second I touched the bowl scraper to the piece, it broke away at the tenon.
torn_tenon.jpgsevered_bowl.jpg

I guess I was just asking for this, with the piece being in the kind of shape it was in. But it surprises me that it was a scraper that caused the break. If it was going to happen, I expected it to happen with the bowl gouge.

Anyway, being as far along as I was, I decided to try and salvage it. I turned the bowl around with the bottom side out, brought the tailstock in and used a friction hold against my chuck as I removed the remains of the damaged tenon with a 1/2" bowl gouge. After removing all I could, I sanded the remainder of the tenon away. I then positioned the bowl with the outside against the chuck, and used the tailstock and a scrap piece to hold the bowl in place as I carefully refined the edges. I'm actually pleased with the save. The bottom is gouged in a couple of places, but given all that's going on with this piece, a gouged bottom only adds "character." Here's the finished prodict.
DSC01061.JPGDSC01062.JPGDSC01066.JPG

Thanks for looking.

Mark

[John Shuk]

nice save!

[Mark Pruitt]

...is what I've come up with after looking further at what happened. The integrity of the tenon was somewhat questionable, so I had reservations as to the outcome before chucking the tenon. When the gouge failed to destroy the bowl, I figured I was OK. (I know...I was playing with fire--but I was using safety precautions to prevent personal injury.) So, why did the scraper--which is supposed to be a fairly benign tool as compared to a gouge--cause the accident? Plain and simple--I think I had the doggone tool rest too far up. DOH! Oh well, the bright side is that I learned two things; how to salvage a bowl with a severed tenon and why the stupid accident happened in the first place.

[Ken Fitzgerald]

Mark.......Nice save! I've got one I'm finishing right now that the same thing happened to it. My save.......I put it in my donut chuck and played with it until I got it centered. I was able to turn a mortise in the same spot as the previous tenon was located. Then I just chucked it up and finished it. The one thing turning is making me do is learning to think out alternatives before I throw away partially completed disasters! Again...........Nice save!

[Travis Stinson]

Mark, I'm not sure if it's just the picture, but in the 2nd pic it looks like there are spaced holes around the circumference of the tenon, like from a faceplate. I'm just wondering if that's the case, the screw holes may have weakened the tenon somewhat. Some of my most violent catches have been with a scraper! They WILL self feed and dig in, depending on how much of the edge of the tool is in contact with the wood at one time, since the speed of the wood increases as you move away from the center. I believe it was Terry Quiram who passed along a tip, from a class with Cindy Drozda, that really tames a scraper's tendancy to dig in. Grind a narrow bevel on the top edge of the cutting edge of the scraper of just a few degrees. It will take a lot of the aggressiveness away from the cutting, but will shave off thin tissue-like shavings while providing much better control.

[Mark Pruitt]

Mark, I'm not sure if it's just the picture, but in the 2nd pic it looks like there are spaced holes around the circumference of the tenon, like from a faceplate. I'm just wondering if that's the case, the screw holes may have weakened the tenon somewhat.

Travis,
The holes were not created by a drill or a screw, they are "in the wood." I guess it's much the same kind of insipient rotting that creates the spalting that you and others have taken such wonderful advantage of in your turnings. I thought I might be able to create something interesting--and I did, just not interesting in the kind of way I had hoped!

Some of my most violent catches have been with a scraper! They WILL self feed and dig in, depending on how much of the edge of the tool is in contact with the wood at one time, since the speed of the wood increases as you move away from the center.

THANK YOU!!! It is very helpful to hear you say that. Now I don't feel quite so odd for having experienced this.

I believe it was Terry Quiram who passed along a tip, from a class with Cindy Drozda, that really tames a scraper's tendancy to dig in. Grind a narrow bevel on the top edge of the cutting edge of the scraper of just a few degrees. It will take a lot of the aggressiveness away from the cutting, but will shave off thin tissue-like shavings while providing much better control.

...and to hear you say THAT, is really helpful. The thought had actually crossed my mind to try and "tame" the cutting edge of the scraper by doing exactly what Terry (and Cindy) was saying to do. Maybe I'm on the right track here.

I know I've said it probably enough to nauseate a few people, but I just can't put into words the value of all that I read on this forum. I sure appreciate it.

Mark