This is to show all readers that mistakes are made and things break.
Skill saw blade I use to hog out hole to rough size got hot and stuck, breaking the clamped part.
As a result I get to repeat about 50 steps to make a new one.
Its all part of fabricating stuff, and it pays to be very carefull with every step or your back to 1st base.
Picture of new part being threaded for nylon thumb screws. "almost done"