[Madler]

Rookie mistake. Took it off too soon. My first bowl on my vintage old Delta lathe. The wood is from a black walnut tree that fell in my yard and it’s exquisite. I see so many flaws in it now and want to get it back spinning to do more intense sanding. Is a jam chuck on both sides the only option to getting this bowl back on the lathe?

 

[yomanbill]

That is beautiful. I would just sand the spots that need it by hand and not worry about getting it back onto the lathe. You could do more harm than good. It looks perfect to me.

 

[firehawkmph]

If the bottom is thick enough you could use a set of bowl jaws and chuck it up and turn a shallow recess in the bottom to match the shape of your regular chuck jaws (either dovetail or 90 degree). then expand the chuck jaws into it being careful not to tighten it like a gorilla, don’t want to split it. The recess only needs to be an 1/8” deep if you have a good chuck.
Mike Hawkins.

 

[Quickstep]

I don’t see the flaws you mention. It looks great!
I’d use a random orbit sander with a soft pad. If you’re not able to secure it well and it flies off, you may have even bigger flaws to address!

To me, sanding while the piece is spinning leaves too many cross-grain scratches, so I almost always do my final sanding by hand.