DIY Hydraulic Shop Press

While taking a welding class I saw a homemade rig similar to this sitting in a corner of the shop. It seems to me like it would work well for simple pressing jobs, like pressing a steering stem into a triple, or bearings into a swingarm ect. If I'm wrong on it, if anyone can add any suggestions on improving design, or other possible uses, please post up.

One trick obviosly is that the jack would have to be centered, which could be done, possibly by welding, or bolting the jack to the lower plate. Since the top of those bottle jacks usually screw in, it might be better to weld that to the floater plate, that would allow the point of contact to be centered at all times.

Disclaimer: I havn't made one myself, but I have full intention of doing so. This is just a sketch based on something I observed.