Hey RoberT 
,
now this looks nice. I have some 4"x4" (10 x 10 cm) here too and was thinking about to use it for a Onefinity table, but I will wait until I have moved to where I can weld one from steel profiles that allows for more 3D space between the rails for a rotary axis.
Instead of screws for moxon visesĀ¹ you could also directly use screws for german/scandinavian front visesĀ², e.g. like shown here: Bench screw for German and Scandinavian L-shaped front vices. They have a part that attaches very simply to a wooden jaw.
1: Double-screw vise, in: Moxon, Joseph: Mechanick Exercises or the Doctrine of Handy-Works. London (1703 edition)
2. German/Scandinavian (L-shaped) Front Vise: Example 1, Example 2, Example 3
I think you will not be disappointed, neither with the machine nor with the software