Don't forget the flat spots

[Ron Stadler]

Posted are the Tulip Poplar hollow forms iv'e been playing around with, one is kind of a dumpy bottom hf, the big one i turned today had a flat spot i didn't recognize when i started the profile so it change my original profile a bit(will have to pay closer attention next time) I still may refine the shape on this one a little. Also put this one in the chuck and it flew off on me on the first touch of my gouge, i now will have to invest in larger jaws for my chuck, i turned the tenon pretty big but the smaller jaws don't have enough surface area when opened up that much to get enough bite, plus my first cut was a little to aggressive i believe. I will order the jaws and then continue on the hollowing part.375056

[John Keeton]

Ron, what size is the larger turning? It appears to be 7” tall or so. A properly formed tenon that is just barely larger than the closed 50 mm jaws should have held the turning without issue. Of course, a dramatic catch can loosen a piece quickly, though a good tenon may well hold the piece. I am not sure you need larger jaws. Reverse the piece with a conical jam chuck in the drive side and reduce the tenon. You may need to true the piece slightly after it is put back in the chuck.

Just a thought.

[Ron Stadler]

Ron, what size is the larger turning? It appears to be 7” tall or so. A properly formed tenon that is just barely larger than the closed 50 mm jaws should have held the turning without issue. Of course, a dramatic catch can loosen a piece quickly, though a good tenon may well hold the piece. I am not sure you need larger jaws. Reverse the piece with a conical jam chuck in the drive side and reduce the tenon. You may need to true the piece slightly after it is put back in the chuck.

Just a thought.
Sounds like a good idea John, I just measure it, it is 9" tall with the tenon, the vessel will be about 8 to 8 1/2.

[John Keeton]

Chuck a piece of scrap wood and turn a cone that will fit the mouth of the form and use a piece of nitrile glove for friction to drive the piece. I assume you have a center mark in the bottom that you can use to center up the form. Should be able to resize the tenon with light cuts. Make sure the cut for the jaws is properly formed.

[robert baccus]

Next time you might try a glueblock--they don,t slip. I use a Hard piece of beech or dogwood ect and screw it on a single screw chuck for a glueblock. Be sure to cut it square after mounting on the screw/lathe. Then use the tailstock to clamp on your vase blank. Use CA and you can use green wood. I do vases up to 125# regularly. Use plenty of fresh thick CA to do this. Piece of cake.

[Dennis Ford]

All of those have potential to be very nice. We all do things a little differently, I would have used a faceplate on the taller of those. It certainly could be done on a chuck with light cuts but I tend to be aggressive when roughing. Some will say that screws don't hold in end grain and it is true that they hold better cross grain, still are stronger than a chuck.

[Ron Stadler]

Chuck a piece of scrap wood and turn a cone that will fit the mouth of the form and use a piece of nitrile glove for friction to drive the piece. I assume you have a center mark in the bottom that you can use to center up the form. Should be able to resize the tenon with light cuts. Make sure the cut for the jaws is properly formed.
well i did what you said and everything seems to be working fine, now is just got to figure out a good way of sharpening my ellsworth hollowing tools