Replacement for Bevel Gears?

[Greg]

I think everyone who saw our bot at the Canadian Regional could hear those bevel gears grinding away when some load was applied to the bot If we have a chance to go to another competition this year, we would definitely like to fix our drive unit.

So, what is a better alternative to bevel gears? Do you think worm gears are stronger? Or can we eliminate the grinding somehow?

The gears are already as tightly meshed as possible, but when the track gets stuck, the torque from our 4 drive motors rips the gears apart Any suggestions?

[sanddrag]

The ones in the kit were helical gears. Bevel gears are quite different. Maybe one team would be willing to trade or give them if they are not being used.

[rbayer]

As mentioned previously, the ones in the kit are Helical gears. Are these the ones you are talking about or did you use bevel gears for something else?

Anyways, if you are talking about the helicals, I can tell you that we used them this year without any problems whatsoever. The key is to make sure you have spacers that are the correct size inside the gearbox and to make sure the shaft can't "walk" out of the gearbox. Here's some pics of our 'bot, which uses both the Chips and the Drills driving the gearboxes provided by FIRST:

http://www.cogsquad.org/image.php?id=34
http://www.chiefdelphi.com/forums/pi...gle&picid=4614

[Greg]

Yep, I've been thinking about these helical gears... To use them we'd have to move one of the shafts down quite a lot. I dont think we have the space, but I'll look at it again when I go to school tomorrow.

We use "extra" bevel gears (that means they were not in the kit). We talked about all these drivetrain problems today, and it looks like we need to support the shafts better (they started to bend - we have tons of power!). This may eliminate the grinding, even with the same type of gears.