crank lift help

I am trying to fashion a set of drop down wheels for a cabinet. These casters are screwed to the underside of cross piece of wood (front to
back). They will be on a hinge so that when they are down they are inside the cabinet, when the cross piece is pushed down, they below the bottom and raise the cabinet.
I would like to have a crank lift where I could insert a handle from outside the cabinet into a recess that contains the end of the linkage to the crank lift itself. If the crank is turned one direction, it meshes a gear which drives a rod down onto the edge of the crosspiece, opposite from the hinges. If it is turned the other direction, then the rod comes up and the weight of the cabinet forces the casters up underneath and inside the cabinet housing. Kind of like the old foot operated sewing machines, but using a crank lift versus your foot to move the pedal.
Any ideas on how to do this "cheaply"? I have seen commercial solutions but they are way toooo expensive.
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Check out the retractable castors made for ShopSmith universal wood tools. I bought a set on e-bay for about 20 bucks. Could hardly make one for less. 73 Gary N9ZSV
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I think, rather than designing with rods, screws, linkage, etc., that I would try to use a "cam" on a pivot, where you could insert a handle of sorts into a hole in the cam, move the cam downward, which would push down on the "2 x 4" or whatever the casters are mounted to. The cam would remain in position until you used the lever to rotate the cam the other direction to retract the casters. Ken.
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The traditional theater-scenery way is to make the plate long and step on it to lower the casters and raise the box. Then slip in a brace to hold it. Could you do it with a hinged toggle linkage that operates by pulling a rope?
The caster plates I've put under most of my woodworking machines are hinged on the inside and swing 180 degrees, in to operate and out under the wall of the base to move. I just lift one end and push the plate in or out with my foot. The plates have retaining hooks for the wheels-down position to pass over a door threshold.
jw
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Hey Chris,
Consider making the "legs" the moving part, and the wheels fixed solid. Easier to work with, and simpler to do. And if it gets too heavy too "lift" somehow, you will still be able to move it. If you use retail hardware like the threaded stem nylon (??) "feet" for say a fridge or desk, then they are adjustable very easily too, or at least much more so than the same on a wheel or caster.
Take care.
Brian Lawson, Bothwell, Ontario. XXXXXXXXXXXXXXXXXXXXX On Wed, 17 Aug 2005 01:58:53 GMT, "Chris Carruth"

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