pic: 2x1 gearbox

[Chak]

Originally Posted by Cothron Theiss

As for the packaging, it looks great! I assume that the gear is exposed more on the bottom of the rail than the top because of the center-dropped axle, so would it be worth making this gearbox direct drive the back wheel instead of the center? That way you can flip the gear cut-outs and have the top side be more exposed. I honestly have no idea if that's worth it; I remember we had issues with the large driven gears eating into the carpet on the 2015 Vex chassis, but that was with gears almost as large as the 4" omnis we had at the time.

If the wheel is directly driven, the wheel would be concentric to the gear and it doesn't really matter which way the gear faces. Currently, the 64t gear has a outer diameter of 3.3", so a 4" wheel should be fine. I actually wanted to use a 3" wheel for 9.71 ft/s, but later realized it wouldn't work.
In the 3x1 version, the 66t gear has a outer diameter of 3.4", which should be fine also.

Originally Posted by Richard Wallace

I am becoming a fan of tube stock transmissions. Our robot included two of them this year, one for shooting and one for intake. Both used 775pro motors.

Thanks for posting this example using CIMs. We may try something similar, perhaps using 3x1. I also agree with those who favor 1/8" wall. Thinner walls make me worry about stress at the bearing seats and motor faces.

Done. http://imgur.com/a/RNfht

Btw, both versions of this gearbox has a SRX mag encoder on the back. Using magnets means that I can loosen a shaft collar and take the output shaft out easily without dealing with the encoder. That makes me a little more willing to have holes blocked by the big gear. Still, as MattC9 said, it's better to have mounting holes that are not blocked at all, so I added it for the 3x1 version.

At this point, this is just a WCP Single Speed Single Reduction gearbox with one less motors and less parts.