Waste block failure and vacuum to the rescue

[Faust M. Ruggiero]

Last night I was looking for a quick project to shrug off a less then enjoyable day of work. I had a piece of oak burl glued to a waste block and decided on a shape. It was a small turning, only 3 1/2" wide and about the same height. I trued the waste block and cut a tenon for the small Talon jaws, rough shaped the outside and without thinking, cut the waste block down to where I knew it would never stand the rigors of hollowing. It was fine as long as the tail stock was supporting it so I wet sanded to 1000 grit, drilled my starter hole and wrapped it with stretch wrap. I set up the bowl steady thinking it might help but the form broke off the waste block within five minutes. So, now I have a beautiful piece of burl shaped and sanded and no way to hold it. Given that the worst that could happen was to ruin it, I decided to center it in a 3" vacuum chuck and give it a whirl. I covered the form with several layers of stretch wrap to seal any bark inclusions. 2/3s of the form was exposed and allowed me to measure wall thickness. I had drilled to 1/4" of the bottom so I was working blind for only the portion that was inside the chuck. I could have removed the piece and measured the wall thickness at the blind portion but chose to see how close I could get by feel. The result was appropriately thin walls in the upper section and a bit thicker than I like on the bottom. It was past my bedtime so I didn't bother remounting it except to shape and sand the base.
The end result was a nice little hollow form that I will show you after it dries and I can get some oil on it and the satisfaction of trusting another way to hold a piece while hollowing it. Having said that, a chuck or faceplate will remain my preferred method.
faust

[Allan Ferguson]

Sounds like a good save. It is said that there is more than one way to skin a cat.