Kong had a setup like that for moving and positioning heavy stuff on the Bridgeport mill.  They don't use air but the elect. industry uses HP oil to "float" turbine/generator shafts before spinning them up.

BB

I use a set of air sleds all the time to move these large boxes we built at the DE Art Museum.  As they change exhibits they change the configuration of the walls in the room.  The boxes are 10' tall, 8' or 10' long, and 2' thick.  We built them from metal studs, 3/4" plywood and 1/2" drywall.  We figure they weigh about 600lbs each.  The air sleds move them with no problem.  The only trick to it is being careful not to let them rock as you move them, and if the floor isn't perfectly flat sometimes you have to get creative with some shims between the sled and the bottom of the box to get a little more height and clear a hump in the floor, etc.

No casters on your lift?

Rudi wrote:

Do you intend on making them or buying?

Depends on price.  I would make them if I can do it with my limited shop capabilities.

The lift came with casters, but they are a joke.  I bent two of the mounts the first time I set the lift on them.  Then broke two casters when I rotated the lift 90 degrees.  Really crappy design.  I think some Dawn smeared all over the floor would work better.  My old lift had similar casters, but they were a lot sturdier.  I gave them to Ernest because I never used them.
 

Thanks, Hornman

Thanks guys. Y’all have taught me something new. Until I did a google search, I was thinking they were beside the muffler bearings. This is some pretty cool tech.

Going the other way, but with only a small amount of suction Mythbusters were able to pick up a car using a shop vac.  It really doesn't take much; surface area is a lot more important than the pressure sued to inflate or vacuum. 

Steve I am following this thread because I've never heard of air casters before and the whole thing is intriguing. I saw how tight your space is in your garage and can see the need for this. Are you looking to keep the air casters permanently under each leg of the lift or just install them when you need to move the lift?
​Trying to Google home made ones I did find a couple of commercial ones that have good pictures on their products. https://www.aerogo.com/products/aero-casters/
 

MS wrote:

Figure a 10” x 10” plate under each leg of the lift will provide 400 sq.in.of lift area. If you can get 20 psi pressure built up under each leg, that woukd lift 8,000 pounds.  The problem is the massive air leak around the 160 linear inches on the perimeter of the plates. I am unsure if a rubber oring near the edge would help or hurt. It only needs to lift a few thousandths of an inch to be able to glide. Figure 0.010” height times 160” length, that makes for a 1.6 sq.in. hole in the air system. I am not sure my 5 hp compressor could overcome that size of a leak.  The number of bleed holes in each plate will need to be designed to maintain system pressure while providing the right amount of leakage to provide the suitable air cushion.

I suppose the test would be to experiment with orifice sizes to see what size hole would still allow the compressor system to maintain 20 psi at full throttle. Then divide by four to get the size of the total of the holes per plate. Then divide by the number of holes per plate (100?) to get the hole size. Then allow for flow restrictions, etc.    Hornman, remember how to do this stuff?

 
Yeah, I remember how to do the flow and pressure loss calculations. I also have enough real world experience to know it is a waste of time to try to do them for something like this, there are too many unknowns to do any meaninful calculations. I have made a couple of the multihole slides (like upside down air hockey tables), that work for low loads for novelty purposes, but don’t work for heavy loads. If you want to make a multihole plate, the total area of the holes cannot exceed the cross sectional area of the air supply line to keep the pressure drops in the right place. That results in either a surprisingly small number of holes, or in many very small holes.

The industrial air slides shown on the sites listed by Mochaman and myself show an inflatable rubber bladder surrounding a single air supply to the inner ring of the bladder. One of the sites mentions “a controlled air leak” around the perimeter where the bladder touches the ground. That air leak is what provides the slide. The inflatable bladder maintains maximum sealing contact with the ground. A wheelbarrow innertube would be about the right size for a bladder. A “biblical” quantity of air was mentioned, and that may be close to correct. As a minimum I would recommend 3/8 air hoses directly from the compressor to each of the four air slides. Considerable experimentation required. One last point: after the slides are installed and ready, when the air is applied to the slides things start moving. If the floor slopes, the load is going to follow gravity whether you want it to or not. That is why the commercial air slide equipment movers usually have tractors fastened to the load, so you can make the load go where you want it to.

Personally I would buy 16 heavy duty casters, build “shoes” that slip onto the underside of each lift column with four casters for each shoe. Then it is just a welding project.