I made my tank cart using space saving spare tires from front wheel drive gm cars. I would use the rear wheel bearing assemblies and the spare tires from the same cars. I welded a plate on each end of a cross tube for the wheel bearings to attach to. I purchased hand rail tubing and pre-made 45/90 degree fittings to weld together for the handle. The deck for the tanks has a angle iron front ledge on it for the rest foot up front. The handle goes down through the cross tube and stops at the floor area. The bottom of the handle and the angle iron front create a 3 point plane for the cart to rest on in the upright position. I used freeze plugs on the bottom of the handle tubes to fit snug enough to be tapped in place with a hammer. This allowed me to make a final level adjustment and tack weld them in place. I attached a ammunition box to hold all of the tips, goggles, tip cleaner,etc, because i got tired of dusting everything off every time i needed to use it. The ammo box has a water tight rubber seal on the lid and id cheaply priced. The advantages of this design are this; heavy duty, rolls over anything very easy (air hoses, tools, 2x4's etc) make it fit just what i have, nothing else, last forever, fairly cheap to make. I should add that when this is in the upright position the wheels are just off the floor. I got lucky taking the handles through the cross tube as this creates a cart that is nose heavy. Olny problem is if you remove both tanks with everything on the cart, hoses, torch head, etc, the cart will flop back to the floor. Just change one tank at a time and all is well.
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