Homemade vise from scissor jack

good job, but personally i would not weld jack to vise or vise jaw,after all its a light duty vise and bolts holding jack in place would take no stress, those jacks dont last long,( acme threads are soft)and then u will need to replace it ..easy and fast to unbolt...and the same as to welding jaw nuts ,,now those may not get used a lot, so they will last longer,i intend to make a medium duty version like this using a scissor jack off a one ton truck , it has 2:1 gear reduction,,to hold electric motor housing while i remover copper windings..with curved jaws to fit housings.

Homemade vise from scissor jack - video