pic: New gearbox CAD

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[sdcantrell56]

That is quite beautiful. However, I have one question...how are you mounting the cims to the plate. It doesn't look like you have any corresponding holes for it.

Originally Posted by sdcantrell56

That is quite beautiful. However, I have one question...how are you mounting the cims to the plate. It doesn't look like you have any corresponding holes for it.

CIM's have 4 holes, two filled with bolts that hold the housing together. That's what you're seeing. The other two are used to hold the gearbox together and to the frame of the bot.

[sdcantrell56]

I still don't understand though. Are you running extra long bolts through the transmission and into the CIM? If so aren't they really small bolts?

[rachal]

Pretty sweet. I love elaborate cutouts. (IN CAD)

[sdcantrell56]

Originally Posted by rachal

Pretty sweet. I love elaborate cutouts. (IN CAD)

Well if you get it cut on a waterjet or laser its not too bad in real life either

Originally Posted by sdcantrell56

I still don't understand though. Are you running extra long bolts through the transmission and into the CIM? If so aren't they really small bolts?

They're #10-32 bolts. Four of them will be more than strong enough to support the gearbox. If my stress tests indicate otherwise, I may add another set of standoffs. We shall see.

[sdcantrell56]

So the holes on a cim are threaded for 10-32? That certainly changes things for the better.

Originally Posted by sdcantrell56

So the holes on a cim are threaded for 10-32? That certainly changes things for the better.

Yep. I remember one year we accidentally used #10-24 on our gearboxes... And I kept wondering why it stripped out all the time.

[sdcantrell56]

HAHA thats never good. Maybe I'll have to integrate that into one of my transmissions.

[Kyle Love]

Whats the estimated output speed of the output shaft?

Originally Posted by Kyle Love

Whats the estimated output speed of the output shaft?

Under load, it's calculated to be around 550rpm. When put to a 4 inch wheel, top speed is calculated at 9.67. I'm assuming 2 inch wide roughtop wheels for this system, but this gearbox could be mated to quite a few different systems.

By the way, if anyone wants the CAD for this, feel free to PM me. It wasn't too difficult to make, so I'd have no problems handing the CAD out.

[sanddrag]

I'd bet you could get another pound out of it in those gears if you wanted to, but overall, nice work.

[=Martin=Taylor=]

What is the advantage over the toughbox?

I like the CIM mounts. That's a very compact way to do it.

[AdamHeard]

Originally Posted by Hachiban VIII

What is the advantage over the toughbox?

I like the CIM mounts. That's a very compact way to do it.

I guess It would be the weight savings.

I'm not really a fan of the same 4 bolts holding the gearbox together, the motors on and the gearbox to whatever structure it is mounted to. No matter what, that is going to make assembly and mounting a much bigger pain that it needs to be. I'll agree it cuts down on parts and weight, but I don't think it's worth it.