Using PTO Hub in Transmission Gearboxes

[asid61]

Neat idea! What's stopping you from putting the bearing in the gear instead of the PTO hub?

[KohKohPuffs]

Originally Posted by asid61

Neat idea! What's stopping you from putting the bearing in the gear instead of the PTO hub?

A gear that rests on a shaft above the gearbox I'm thinking of would not be able to fit in the space between the DOG gears (can't really go outside of it because the CIM pinions wouldn't be able to reach it)

I kinda realized that this is a bit dumb; if you're going to make your own gearbox, then by that same process you might as well custom machine a gear to have the dog profile (unless somehow it's preferred to minimize machining time as much as possible)

[aJASONt_angles]

Cool Idea! I agree it might be heavy/unnecessary for a final gearbox but I think this would make an awesome prototyping tool.

[Chris is me]

Originally Posted by KohKohPuffs

I kinda realized that this is a bit dumb; if you're going to make your own gearbox, then by that same process you might as well custom machine a gear to have the dog profile (unless somehow it's preferred to minimize machining time as much as possible)

It's way easier to machine gearbox sideplates or gearbox shafts than it is to index and machine even a COTS gear with non-revolved features like dog teeth. They're both certainly possible, but it's just more effort to get the machining on the gear concentric than it is to mill out a gearbox plate from stock. I'd probably do something like this if I wanted to use a different dog gear; it's a good solution I think. I don't see why this wouldn't work.

[Joe G.]

Originally Posted by Chris is me

It's way easier to machine gearbox sideplates or gearbox shafts than it is to index and machine even a COTS gear with non-revolved features like dog teeth. They're both certainly possible, but it's just more effort to get the machining on the gear concentric than it is to mill out a gearbox plate from stock. I'd probably do something like this if I wanted to use a different dog gear; it's a good solution I think. I don't see why this wouldn't work.

Yes, machining a dog profile into a steel sprocket on a manual mill was an experience filled with pain and regret. It's easy enough with the right resources, but custom gearboxes can easily be built without them through techniques like this.

[Cothron Theiss]

I wonder if you could actually print this hub? Not out of ABS or PLA, but something more substantial, like Ultem 9085 or even 1010 if you can get your hands on the blasted stuff. I know that if you shift at the appropriate times for whatever ratios you have, the forces on the god would be much smaller, but they'd still be significant. Maybe having a pretty slight first reduction so that the shifting occurs at a higher RPM with less torque?

It's probably not practical to print it, but it might be interesting.