Saddle tee hole drilling setup - photo

Saddle tee hole drilling setup.

Fullsize image: https://diqn32j8nouaz.cloudfront.net...t_fullsize.jpg
https://diqn32j8nouaz.cloudfront.net...oter_mount.jpg


Previously:

https://www.homemadetools.net/forum/...914#post179461
https://www.homemadetools.net/forum/...578#post166813
https://www.homemadetools.net/forum/...101#post153568
https://www.homemadetools.net/forum/...907#post152752
https://www.homemadetools.net/forum/...241#post176855
https://www.homemadetools.net/forum/...147#post176490

Not an extraordinarily tough fixture to build. Even a chain vise would be good for a basis, including a flat or inserted bubble level.
I'd guide with a pair of inch or so bronze bushings spread apart and a fine thread large diameter lead screw for that knob. Bushings would allow an aluminum frame; for hoisting that puppy overhead.