Designing a custom gearbox

[Dival]

My team is thinking about designing a custom made gearbox for the slide drive. It seems like we need a low profile SS gearbox for 1 CIM motor. We have a sponsor's workshop that can do the CNC work for us.
We will be gratefull for any tips that will help us design and manufacture it. We are especially worried on tolerance, bearing holes, and the choice of gears (currently thinking of using vexpro aluminum gears), but any other tips would be highly appreciated.

[RobbyD]

973 actually posted a very good youtube video following through custom gearbox design https://www.youtube.com/watch?v=GCjBx3TXB6Y

I think the actual gearbox bit starts around 19 mins in.

For my team, we usually like to have at least 2 or so pieces of round tube as standoffs somewhere in there (with symmetry if possible). Those tubes are usually inset into the .25" alum plates about .125" so they stay concentric with their bolts and nothing shifts around. I used to make the annoying mistake of jumping straight to weight cutouts way too early and having to redo them over and over again, so my general rule of thumb at this point is to not move on to weight cutouts until I'm 100% confident in the geometry and have had several mentors approve everything. 973 also posted a very insightful look into gearbox weight cutouts. Hope that helps!

[Dunngeon]

Another alternative to the 973 video is the 610 Design files. I really like how it lays out gearbox cadding, and it's how we introduce basic gearbox design.

You can find it here,
http://team610.com/wp-content/resour...orialsRev7.pdf
There's a parts library too, if you're interested in that. Search for it.
It also covers fastener types and linear motion.

Good luck!

[Lil' Lavery]

What size wheels are you using? What is your target speed? In terms of creating a low-profile solution for a single CIM, it's hard to beat achieving all the reduction you need in a single reduction that directly drives your wheels.