Gearbox Question

Here is my gearbox idea:

Do you think I have enough support to add a sprocket to one of the axles sticking out? This is cantilever right? (forget the gears rubbing the metal. I didn’t want to fix it in CAD…)


For a drivetrain? if so then i think it’ll be fine. I’ve seen cantilevered gears before with aMess round up

Tabor, you a funny guy. How does cantilevering my lift make it better?

On Topic:

Could I get away with using the Low Strength 36t Gears for this? This will be for the drive.

The cantilevering joke comes from Kyle (Android) using cantilevering extensively on his sack attack robot and presumably his toss up designs, which were fairly successful and therefore “better” than other designs.

Personally, I try to avoid cantilevering because of its theoretical flaws, but its been shown to work decently well in empirical testing. I certainly wouldn’t cantilever a lift.

Cantilevering gets a bad rap because it’s very easy to visualize how it can go horribly wrong, and in fact its pretty easy to design things such that it does go horribly wrong. However, if you do it smartly, cantilevered joints can support just as much load as a dual supported joint. Always use two bearings, and keep the cantilevered load as close to the bearings as possible. While I wouldn’t go out of my way to do it with no reason, there’s no reason a lift couldn’t be cantilevered if circumstances forced it.

I just deleted 5 posts from this thread for being off-topic inside jokes. Let’s try and keep things focused here. There are plenty of other places on the internet for everyone to share their inside jokes.

Have I cantilevered smartly? What would you change about this to make it stronger; or is it strong enough?

As pictured, nothing is in cantilever in your design. If you were to put a wheel or something on one of the shafts extending out of the gearbox, the wheel would be cantilevered. Assuming that the two C channels are solidly mounted, and that you don’t mount your wheel more than a half inch or so from the outer C channel, I’d say you’ll be fine.

In general, the further apart your two bearings are (within reason, at a certain point shaft flex will actually lead to a weaker cantilever with wider bearings), and the closer you can make your load to the outermost bearing, the stronger the cantilever. Shifting the outer bearing to the opposite wall of the C channel, for example, would be a small change to improve the cantilever quality further.

Going by the Inventor pic you posted I would think it is very adequate as is. If you can replace the nylon bushings with another bearing block that would be a little bit of insurance, but I cannot imagine what you have not working unless you are using 12" axles.

OK. Thank you guys!