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Hydraulic Shocks - how to get/install/use them...? Answered

I recently obtained a nice massage table for my wife (she does massage, studying to be an aesthetician too)... and it has a very nice feature; beneath the head-end of the table, there is a little lever, when depressed it raises from flat to about 60 degrees; and stops at any point in between as soon as the lever is released. And it stays there, even with most of my weight (250 pounds or so) pushing down against it. As soon as you press the little lever, it can be moved up or down again.

I looked it over, and much of the mechanism is hidden, but I can see it relies on a (deceptively small) gas shock or hydraulic shock, like what is used in many car trunks and 3rd/5th door lifts for SUVs and hatchbacks. Though, obviously much stronger than those devices.

So my question is, where can I find one of these things, and how does it come to be controlled by a little lever so that it can stop at any given point and bear a load without moving until the level is once again depressed?

The main reason for my query is that the massage table is too narrow by far, and I plan on making a bigger one for her, with a few nicer features; but that is one I have no idea how to duplicate at the moment!



I tried but I can't find these things. If it doesn't move when locked it'll be hydraulic, but all I get are mining / construction / automotive...


Here's some cameraphone images in a dimly lit room...

hydraulic.jpgcloseup lever.jpglever.jpg

. I can't figure out how anything in those pics would cause anything to lock in position. :(

Pressing either end of that bar, near the black rubber caps, up towards the table unlocks the bed so it can raise or lower. Letting go locks it into place so firmly that I can put my full weight on it, pulling down from below, pulling up from above, or pushing either direction as well, and not move it at all.

As soon as the handle is depressed, it moves; fairly easily upwards (but not on its own, it still requires a little force to pull it up), and less easily downwards (so when someone is laying on it, it doesn't just fall flat, but slowly glides to flat)...

I'm guessing it is some kind of specialty mechanism that only bears a superficial resemblance to the gas shocks/struts used in car trunks and whatnot...

It seems that he would need to machine the same fitting that the end of the lift piston is attached to. Since the angle of the back of the bedrest never goes to vertical, the weight is actually pushing the strut sideways on top of the piston and not up/down causing it to move. The tension must be adjusted/balanced so there is enough friction to keep it from moving up/down. Probably why you need that big grab bar to push up and down on it.

Why not try a whole bunch of trunk-lifting mechanisms?

(Actually, you may not need many - those big SUV back doors are heavy.)

That was my first thought as well; but the key is how to get it to lock at any position, with a lever (or similar mechanism, as long as she can easily manually adjust the height, and then lock it in place)... any suggestions?