Self centering vise for cubes?

[HeuristicBishop (Tyler Sowers)]

Oh this is going to be a fun rabbit hole

Longworth Chuck Sizing

I am going to make a Longworth turning chuck for some friends on my SO3. I found a good svg on Woodworkers Journal for a 12" and 16". The problem is the 12" one is fine but the 16" just seems like someone simply increased the size and the slots were made bigger. My question is how to reduce the slots from 3/8" down to 1/4". I tried to create the Longworth chuck from scratch but had problem getting my boolean working. A Longworth chuck is simply a series of 8 circles. However they are only …

Did you ever get around to making your indexer?
Manual 4th axis - self centering

And increasing the diameter of the turret seems to have done the trick. Also added diameters for 50mm and 30mm.