How to use a bag motor or a 775 pro motor?

Technical Motors
1

I’m really confused by the round shafts of these motors. I tried the FTC motor hub(http://www.tetrixrobotics.com/TETRIX_Motor_Shaft_Hubs) but it just came of as soon as the motor started spinning. What is the correct way of using these motors?

2

Use vexpro versaplanatary gearboxes.

3

press fit a pinion like this on the 775 motor

http://www.wcproducts.net/wcp-0002

4

The way motors like the bag or 775 work is that as opposed to using a keyway in the shaft they either have you attach something to the shaft with a setscrew or by pres fitting. The versaplanetaries above mentioned use pressfiting which if you are new to it may seem weird that it actually stays on. Basically the hole on the pinion gear or pulley is just a tad bit smaller than the diameter of the shaft.

5

@rsisk To use this gear I need to design an additional gearbox right?

6

Thanks. I’ve never tried press fitting before, indeed weird for me. Are there any tutorial?

7

Thanks, but I think the versaplanatary gear box simply takes up too much space.

8

You’re either going to have to press fit a WCP gear, press fit a WCP pulley, or use a versa planetary gearbox. The first two options require you to make a gearbox.

Do you have a picture of the specific application you need this motor for?

9

Thanks. I’m thinking about using two RS775 to power the ball shooter in this year’s CRC. I’ve just checked the WCP gear and pulley you mentioned but found them both out of stock. In this case I think I should better design a press fitting pulley instead.

10

The easiest way to do that would be to use one of those https://www.vexrobotics.com/vexpro/motion/217-3141.html

Here’s an imgur album of how I’ve seen it being done; http://m.imgur.com/a/w2TvR

11

Another option is to press fit a hex shaft adapter with a set screw onto the motor shaft. We used this on out updated 775pro shooter and it worked well.

12

If you are at the point where you are learning how to attach motor outputs to a system, you should probably be buying a gearbox. The simplify in mounting and use of an off the shelf gearbox is what you want. Designing your own gearbox or power transmission system is going to be a huge waste of time for you.