Was asked by a new member how to turn this NE bowl with a round bottom. Here’s a hasty adhoc answer using misc archive pics pasted together to tell the story. The process is the same or similar for all. This is old school Pattern Maker’s style and you should be adept with your tools and confident in your ability before attempting some of these techniques.
Start with the blank mounted between centers to do the rough turning while reading the grain and adjusting for balance and symmetry. Once roughed out turn a flat spot to mount on a faceplate with waste block.
Turn the finished shape and sand the outside to the waste block. Don’t cut too deeply into the waste block yet, need it’s mass for hollowing, and leave enough to complete the arc while allowing room to part off.
Hollow turn and finish sand the interior. Use Extreme caution sanding with a natural edge, it has been accurately compared here on WB to sanding the inside of a spinning hole saw... Reduce the waste block and continue shaping the bottom. Can go as small as you dare but remember you’ve got time invested so don’t get too crazy and risk it breaking off. Cut the remainder with a saw.
Use a proper fitting jam chuck and mount with the tailstock cup center holding it on, then turn away and sand as much as possible. Securely mount the jam chuck in a vise and pare the nub away with a freshly honed chisel then hand sand to completion. A vacuum chuck would be ideal to finish the bottom.
Hope you get the jest of the process. The natural edge greatly increases the pucker factor, recommend try it a few times with a flat rim and feel comfortable before you stick your hand into the jaws of the beast. Will document the process with pics and post it next time I make one.
Start with the blank mounted between centers to do the rough turning while reading the grain and adjusting for balance and symmetry. Once roughed out turn a flat spot to mount on a faceplate with waste block.
Turn the finished shape and sand the outside to the waste block. Don’t cut too deeply into the waste block yet, need it’s mass for hollowing, and leave enough to complete the arc while allowing room to part off.
Hollow turn and finish sand the interior. Use Extreme caution sanding with a natural edge, it has been accurately compared here on WB to sanding the inside of a spinning hole saw... Reduce the waste block and continue shaping the bottom. Can go as small as you dare but remember you’ve got time invested so don’t get too crazy and risk it breaking off. Cut the remainder with a saw.
Use a proper fitting jam chuck and mount with the tailstock cup center holding it on, then turn away and sand as much as possible. Securely mount the jam chuck in a vise and pare the nub away with a freshly honed chisel then hand sand to completion. A vacuum chuck would be ideal to finish the bottom.
Hope you get the jest of the process. The natural edge greatly increases the pucker factor, recommend try it a few times with a flat rim and feel comfortable before you stick your hand into the jaws of the beast. Will document the process with pics and post it next time I make one.
