Thanks for all the input, very helpful.
I'm flexible, not married to any particular design.
If it was 20 years ago I'd definitely build my own. The last shop I built I just put in a single straight beam on posts with a trolley. If I have to I can live with a single beam spanning two work bays ... could be used for unloading a truck onto the shop floor, or loading from the shop floor to a truck.
Rolling gantry would also be a possibility. The more versatile the crane better, kind of why I liked the single girder bridge crane looks so attractive.
I'm a big fan of beams .... I built this truss beam with 20' span so I could remove a structural post in our kitchen. It supports another post upstairs that supports a ridge post and supports all the floor joists. Deflection when I loaded it was 1/16" in the middle. Zero bounce when jumping up and down on the floor upstairs. It's all square tube structural steel ... 12ga walls I think, all built up from 2 x 2" square.
PS. Thanks 4zpeed .... that terminology got me much better results in my search.
