Hi Rick,
I have a small batch of the original gearboxes that were returned for one reason or another. So a replacement gear wouldn’t be a problem. Just need to ask. 
The place making them was a startup business. They had some quality issues, so I left them to work out their issues. I have made contact with them again, actually lost the info for a while. I just need to do the foot work to get them going again. Guess I have to now… lol
Found a new place to get gearboxes. These are designed specially for the cobalt motors pictured earlier in this thread. This image is of the prototype. Waiting for them to get here. And it only took me 6 and a half months to get to it! 
Nice looking gearbox Jim, a note about using the belt drive set-up. Beld drive is a very strong set-up as long as it is configured correctly. Belts with kelvar is the way to go do to their tendencie to streatch less. There is a reason Harley went to the belt drives on the bikes, strong, and virtually maintenance free. The only downfall I would see in the application is the pullies not the belt. The pullies need to be of good enough quality so that it meshes with the belt smoothly without play in the mesh on the teeth of the belt. If there is play there you can tear teeth off in hard direction changes. Just a thought for you to look at in assembly of the drives.
Another thought too is to use a belt that is as wide as allowed in the pully, a belt that is the full width will wear less than one that has room to move side to side.
Yeah I know there are hurdles to overcome. I’m very likely to convert this to 4 wheels instead of 6. This will reduce the complexity and improve the efficiency of the entire drive system. Can’t wait to get the gear boxes here so I can finally get this guy moving! 8)
Jim,
That gearbox looks wonderful, obviously very high quality. Too bad I am not building a 3Kg sumo.
March is only four months away.
Rick BrooksHello Jim,
Great start to your bot!
I know all about chasing the guy in 1st place.
This was my first entry into 3kg Sumo & where Rick brooks embarassed it by beating it with Expendable.
thebabcocks.us/1st.htm
I made it my mission to get even. 
Here was my second attempt:
thebabcocks.us/2nd.htm But lost again due to a bad plow design.
3rd time was the charm with my tracked revision:
thebabcocks.us/3rd.htm Victory!!!
Here are more pics if anyone is interested: thebabcocks.us/sumo.htm
I used custom conveyor belts for the tracks. The only bad part was I didn’t do my research first and built it to the NEIRG Rules and it’s a 22cm 3kg robot so I can’t compete it anywhere else.
Nice bot! where’s the videos? 
I don’t think I have any… 
I just got it working again, bad batteries, so I upgraded and went upto 8 cells to increase the speed. I’ll have to take some new ones and maybe post them this weekend.
Wow you even posted his winning match. What a standup guy. Thanks Rick!
Thanks Rick!
It would only be fair to post this one then:
brooksbots.com/Movies/NEIRG%2005/9b%20Titan%20vs%20Sticky.wmv
Hi Brandon (aka Trackman),
I wondered what happened to you and Titan. Are you planning on a return to NEIRG in February?
It will me more interesting at the CIRC Bot Brawl with Jim’s new robot to go against Executioner and Cheeky-san. Perhaps Mike an I won’t have to drag out our old 3Kg sumo robots (Brutus and Excuse) to fill out the field.
Titan is a very interesting robot, it would be good to let the competitors in Peoria see it. Perhaps you could enter it in the “Best in Show” class there.
Rick BrooksHi Rick!
Titan got lost in a move & while in storage had one of the Nimh cells explode and leak all over. 
It’s all cleaned up now, new nimh cells, went from 6 to 8 cells to increase the speed a little. Titan is a little slow, but better now. Also changed some sensors and re-wrote all the programming to get rid of some bad code. I’ll be at NEIRG, and CIRC sounds like it would be cool to go to too.
Jim,
Only two months to go and still only one 3KG sumo registered! Enough of playing Santa Clause for all of those robot builders of the world. It is time to get building.
Look at all of those prizes! circ.mtco.com/
I’m building a new, fast line follower. I think that I’ll call it Fireball after probotix.com/FireBall_v90_cnc_router_kit/. That is the easy way to build robot chassis.
RickI know, I know… I have made zero progress since I received the sample gearboxes. Dunno if I will make it or not.
SO what will happen to the robot? DO you have any of the latest picture on the robot?
I haven’t been able to work on this for a long time. Not sure if it will ever get finished.