I needed 3 dog point screws for my new heavy duty tripod. Already had some nice brass thumb screws but they lacked the dog point.
Shelley had a nice one on Homemade tools a few years back that I liked so I made my own version based on his pictures.
Here is the link for Shelly's version..
Here is the link for my Heavy Duty Tripod..
I used a 7/8-14 piece of all thread for the arbor and some mystery metal (hot rolled 1.25" dia) for the "lantern".
It has a capacity of up to 5/8 inch using bushings of the proper size to fit the screw.
The screw is held captive by the head and threaded arbor. It gets tighter as the screw is turned in the lathe (ccw of course).
Simple flats on the arbor and lantern are used to tighten or loosen the screw in the chuck.
Bushings were made in two types. One that is threaded to be used with set screws and the other type
which is not threaded but a close fit for the nominal screw size.
Spacers were made to keep the stickout short. Works fine and hope it lasts a long time.