A while back I Reverse-Engineered the HO scale Overhead I-Beam Hoist Rusty Stumps had produced as White Metal Castings.
The photo to the left is from the Rusty Stumps website as built by Walt Gillespie. I haven’t actually built this myself .. credit that to the problems with designing something and having to have it printed remotely. That means creating a prototype is somewhat difficult since the procedure requires you upload a file to Shapeways, have the part printed, have it posted to me, examine and make changes, upload the new file to Shapeways, have a new model printed .. etc.
This properly I think is a combination of what is called an “Overhead Trolley” and a “Handwheel Hoist” into what Walt titled “Overhead I-Beam Hoist”.