[Rauhul Varma]

Originally Posted by mman1506

Did you machine the output shaft with a 4th axis?

Originally Posted by kitare102

From what it looks like, all you'd need is a 3-axis mill and lathe. Turn the sucker down, mill the two holes and set up the piece in a rotary table to make the hex end.

We used a lathe to turn the counter and bore, then mounted the shaft in an indexer on a manual mill and made the ball cavities and the hex with 2 work holdings.

Originally Posted by highlander

What was the rationale behind not adding more ball's for each gear to make engagement faster when you shift? Also, what is the benefit of adding ball bearings (my guess at what those depressions in the gears are for) as opposed to the bushings that VexPro sells with their ball shifter gears?

With a .625” OD this driveshaft is smaller than the drive shafts on the Vex Pro gearboxes. In addition it’s 7075 aluminum not hardened steel, so introducing a fourth ball could have made the shaft susceptible to shear failure. Even if the shaft was strong enough for a fourth set of balls, it would have taken too much time in analysis to prove for the marginal gain in shift speed.

I used bearings in the gears because they’re more efficient than the bushings. They are slightly bigger but that didn’t hinder the design very much.

Originally Posted by highlander

Thanks for posting these pictures; very useful into seeing how this great gearbox was made

No problem! Just wait for next year's gearbox, we have big things in store.