Integrating VEX EDR Wheels with FRC Motors

[Dalas]

We are thinking of using a VEX EDR shaft (http://www.vexrobotics.com/vexedr/products/accessories/motion/shafts-and-hardware.html) with VEX EDR mecanum wheels (http://www.vexrobotics.com/vexedr/products/accessories/motion/edr-wheels.html) on our ball intake system. Ideally it would work something like this: https://www.youtube.com/watch?v=WwxNSiHXREo

While using these parts is definitely not ideal, we don't have the time or money (especially money) to buy the equivalent 1/2" hex VEXpro versions.

Can anyone give some advice on possible ways to integrate these wheels/shafts with FRC motors? We have CIMs and Andymark PG-class gearboxes with RS775s to drive them with; the CIMs would probably need to be geared down and the PG/RS775s would need to be geared up for the intake to work well. We have plenty of KOP gears, pulleys, and belts, but not much else to work with.

[Peyton Yeung]

Are you near any teams with a 1/2" hex broach? If so you could ask them to broach the wheels for you.

[Collin Stiers]

do the wheels have to be on a vex shaft?
Vex wheels have a piece of plastic in the center that has the square hole for the shaft. If you removed that piece of plastic you would have hole almost the right size. Or you could then use VEX high strength shaft, because it is larger it might be easier to make an adapter, you could perhaps 3D print one

[Dalas]

Are you near any teams with a 1/2" hex broach? If so you could ask them to broach the wheels for you.

Unfortunately, the center plastic is barely 1/2" in diameter, so I'd be worried about the wheel breaking if any torque was put onto a 1/2" broached hex hole. I'll keep it in mind as an option.

do the wheels have to be on a vex shaft?
Vex wheels have a piece of plastic in the center that has the square hole for the shaft. If you removed that piece of plastic you would have hole almost the right size. Or you could then use VEX high strength shaft, because it is larger it might be easier to make an adapter, you could perhaps 3D print one

I'm not sure what you mean. As far as I can tell the mecanum wheels are molded out of one solid piece of plastic, with rubber rollers attached separately. The wheels do not have to be on a VEX shaft, in fact I'd prefer it if they were on a 1/2" hex because the VEX shafts are very bendy. We do not have any high strength shaft to work with, and while we do have access to (low quality) 3D printers we have no square broach to make a larger center hole with. Keep in mind the VEX wheels have no mounting holes except a square hole in the center for a shaft.

If we really needed to we could try and drill mounting holes for an FRC-standard hex hub, but I'm worried we would screw something up and ruin a wheel (we need all 4, ideally).

[Chris is me]

Unfortunately, the center plastic is barely 1/2" in diameter, so I'd be worried about the wheel breaking if any torque was put onto a 1/2" broached hex hole. I'll keep it in mind as an option.

While I haven't run the wheels for a whole season or on a drivetrain, you can totally hex broach Vex wheels and it should work fine for something like an intake mechanism. I've done it before for intake or shooter prototypes without problems.

[Dalas]

While I haven't run the wheels for a whole season or on a drivetrain, you can totally hex broach Vex wheels and it should work fine for something like an intake mechanism. I've done it before for intake or shooter prototypes without problems.

Ok, sounds good then! Thank you all for your help, and good luck!