Ball bearing changer.

[Johnie King]

Nice changer design

[Colin Boutilier]

I'd be inclined to try fine needle bearings on one, vs the sealed balls, or maybe a brass roller bushing... I love how many different approaches there have been to what amounts to the same design challenge.

[John Haspert]

Wouldn’t a bearing with a bit of pre-load distribute the load to all of the elements of the bearing? Also, rotation at string change is an excellent idea. Lastly, a sealed bearing with an “Arctic” rated lube for a low viscosity base fluid and lower operational friction would ice that cake nicely!

[Kenny Davis]

Ricky: Did James Morehead use Coop bearings on y'all's prototype or his own? I understand they were needle bearings at the changer.