Who needs a lever, man? I’m Marty McFly.

Let’s say, for the sake of argument, that you needed to move a heavy piece of equipment you’re helping to build. And you have the constraints of not wanting to tip it, and the course you need to navigate has some spots with less than 10 cm of overhead space. (This ignores one doorway that’s actually 10 cm too low — yes, we’ve done the equivalent of having built a boat in our basement. The solution there will either be slapping Daffy Duck with a frying pan in the shape of the equipment and having him run through the door, or a sawzall.) You need a smooth ride, because it’s an expensive, somewhat delicate trinket representing a several dollars and a few person-years of labor.

I tried designing a cart, but couldn’t meet all of the constraints — anything low enough would tend to bottom out on the incline (oh, that’s right, the path isn’t level the whole way. Is that a problem? I need this soon.) One day I was stressing and kvetching about it in front of the right person, who suggested air bearings/air casters. The heretofore unconnected link between the physics and the application clicked, and I knew that was the answer. Float the sucker on air. A small industrial blower and lots of small holes.

Here’s a demo of the system with a dummy load. There are also some lead blocks there, too. (cue rimshot). 160 kg for the optical table, lead and support structure, and another 110 kg or so for me.

(if you want a soundtrack, turn on a vacuum cleaner. Any “Ishmael” wisecracks about my pasty-white legs will be subject to retaliatory editing)
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