The best castors/wheels I use on equipment here have full span bearings instead of the small sealed bearings pressed into the hub on each side. My large hand truck has four such wheels, two per side, with rollers approx 4" long surrounding a 1" diameter axle in each wheel hub. That hand truck (setting truck) will easily move a 1000lb-1500lb stone of you can handle it. These aren't cheap, but they're the best. Very smooth and stable. There are smaller versions available. Either are probably overkill but would handle the weight without worries. If you cannot find what I'm talking about, send me an email.
Not sure what length you plan to make, but using a pair or more of conveyor rollers mounted in a semicircular chassis underneath the tube would probably be a better way to go. Very stable. If they are the better kind with good bearings, they'll last a long time and this would be very space-efficient. The tube rollers would be my choice over ganged wheel rollers.
A pair of pillow block bearings, one mounted to each end of the cylinder, is another option.
Tumbling parts may be ok for some things, but a vibratory unit would be safer to keep corners and edges from damage. What kind of media do you plan to use?
1967 Galaxie 500 Red original Q code 428
1967 Galaxie 500 White with Black stripes 428PI clone- car is dead & long gone, sold near Oak Ridge TN 2000, would love to find it.....
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