John Lucas
I made this collet chuck to hold the upper finial of the Genie bottle. I made the hole in the bottom the same size as the top of the final and as deep as the finial. Then I hollowed out the near end to slightly larger than the threaded end of the finial. I cut slots in the wood so it would compress. I installed a hose clamp to compress it. After I installed the finial and tightened it down it was quite easy to hollow out the inside of the finial.