Courtesy Classic Oilfield Photographs
Another example of wheel construction for cable tool rigs. The bull wheel spooled 1 inch to 1 1/4 inch hemp rope, several thousands of feet of the stuff, used to raise and lower the bottom hole assembly, bail cuttings from the bottom of the well and pick up casing, etc. The spindle of early bull wheels were actually made of wood but were problematic with increasing hook loads as wells got deeper. They broke all the time. By the turn of the century most bull wheel spindles were made of steel and, like this one, wrapped with burlap.
Please note the wooden dowels; to insure the outer facing stayed attached to laminated wheel, holes were drilled and wooden dowels driven into the holes. Like all wood, these dowels would swell and become as tight, or tighter that iron bolts.
This is an actual cable tool rig that has been preserved and is located in Casper, Wyoming. The bull wheel is located far right on the rig floor. This is a terrific photo; please remember the band wheel turned the pitman arm(s) that made the walking beam go up and down and raise and lower the bit downhole that pounded its way, hopefully, to pay dirt. Here we can see all the major components of a cable tool rig, save the steam boiler/power train. Photo by C. Swackhamer.