There are many ways to reverse a bowl and mount it to finish out the bottom.  Here is one method I often employ.

 

After turning the bowl as much as possible mounted in the chuck I then get out my biggest face plate and mount a piece of MDF to it.  I use a set of calipers set to the bowl's rim diameter and mark the diameter on the MDF.  I use a small Bedan type tool to make a cut for the bowl rim to sit in.  I creep up on it to get the snuggest fit possible.  As you can see the MDF can be used for many bowls before it needs replaced.  I've been using this one for awhile.  the groove only needs to be deep enough to keep the bowl in place.

 

 

I've been lucky enough to sometimes get a press fit and the bowl will stay in place on its own.  If not I put four screws around the perimeter and I guess tie the bowl to the face plate using 2" stretch wrap.

 

 

The bowl is held very tightly and the bottom is easily finished and sanded.  Just keep your hands away from the screws.

 

 

This is the safest method I have ever used and have never lost a bowl.  It is also the best method for centering the bowl too.  I have a set of flat jaws and use them but also employ the stretch wrap when using them.  I screw some sticks of wood on each jaw for the stretch wrap.  The flat jaws get the bowl close to center but the face plate method is best.  IMO of course.  Below is the bowl you see mounted.

 

 

 

 

 

 

Edited October 4, 20214 yr by HandyDan

Love it! The only thing I do differently is use that "filament strapping tape" instead of the stretch wrap. Sounds like your method may be more economical.

I never had good luck with this myself. Prefer vacumn chuck. Saw Stuart Batty do this and actually returned the outside thinner. That was amazing. Oh by the way only some blue tape around the rim.