The kit comes with those helical gears that have 1/16" wide keyway and the 5/8" shaft with 1/8" wide keyway. I see the key stock for this application. Is this key stock good enough to hold these helical gears in place on the 5/8" shafts, or do I need to use a collar or something else to prevent the gears from sliding axially along the shafts?
I had the same quesiton … we have these gears installed on the shafts using the stepped key stock, but one or two of them can still easily slide along the axis of the shaft - also without collars the entire shaft can slide within the bearing inner race. I don’t believe FIRST provided collars for the 5/8" shaft (unless I missed them), but then how did the FIRST engineers build a “working” robot chassis at the kickoff using only parts in the kit?
Stu Bloom :ahh:
Mechanical Engineer - Rolls-Royce Corporation
Pike High School RoboDevils - 1018
Errrrmmmm… That oddly shaped key stock is what your talking about right?? That should fit in both the gear and shaft very hard and should stay put.
We built up the supplied gearbox using just the key stock and when we tried it, the gears did NOT stay in place. Collars with set screws will be required, at least for ours…
There are retaining rings provided in the kit. They look like a washer with teeth. They slide on one way but don’t slide (easily) the other. I would suggest making spacer out of the aluminium tubing they sent you to space the gears off of the bearings inner race. This is what it looked like first did. They don’t show it in the expanded view but if you took pictures you can see it on the robots from first.
http://www.archergeeks1022.org/photos/Manchester%20Kickoff/index.html
Also don’t forget to have clearance for the inner race of the bearing that goes up against the aluminium channel. I hope that helps.