I want to build a steel cart with four hydraulic bottle jacks attached to it that can move my Bridgeport mill. The idea is to avoid the safey hazzards and hassle associated with using an engine hoist or pallet jack. I want to be able to move my mills around the garage on a whim, and without needing a second person.
Recently, I started a thread asking if a pallet jack could be used to move a Bridgeport sized mill. The answer is yes, but not very safely.
http://www.cnczone.com/forums/showthread.php?t=19435
So here's my first attempt at mocking up the idea. Just a bunch of 4" square steel tubes. The dolly can adjust to differnt size pedestals for a range between a series I mill and a Series II mill. The size can be adjusted by sliding the red tubes through the corner brackets. I'll pin the tubes in place, sort of like my adjustable shop crane from Harbor freight.
The small orange cylinders are cheap 4ton hydraulic bottle jacks. I picked up 4 of them today from Harbor Freight for about $45 total.
The yellow parts are intended to sit on top of rollers. So to lift and move a mill, I would assemble the pieces around the mill's pedestal base, adjust to size, and start jacking the mill up. Once it clears the ground, I should be able to start moving right away.
One problem is weight. I think I overdid it, with 3/8" wall thickness. My CAD software predicts a weight of almost 1000lbs for just the dolly! Any ideas? I don't have a good feel for how thin to make the walls, or what size tube to use. I want this thing to be able to handle moving up to a 4 ton mill.
This is still the pie-in-the-sky design stage, so I welcome any criticism, pointers, ideas, or questions!