Make An Electric Crane Combine Forklift

[Frank S]

There is no question about it these little portable cranes are super handy on perfectly flat smooth surfaces. But even with a perfect floor surface the small diameter of the wheel are a detriment when having to move and position the crane while loaded with very much load.
A good example of this is to try and roll a 2 ton rated engine crane around with just 500 lbs hanging from the hook on a chain. Over coming the rolling resistance can be a challenge even on the best of floors . Something as small as a 6-32 nut will stop you cold in your tracks with 3" wheels increase the load to 1000 lbs and a 1/4-20 will do the same thing with 5 inch wheels with 3000 lbs a 1/2" bolt 1" long will stop anything short of 12" diameter pneumatic tires.
it doesn't have to be any foreign debris to stop small hard wheels it can be a simple expansion joint in the floor or pavement or a grouted tile joint when it comes to small wheels