pic: Team 1388: Loosing weight

Start off, with a IFI Transmission kit. Turn down the centers of the internal gears (not shown in this picture, but there are pictures from other teams who have done it here). Next, take the output sprocket, and turn that down. Turn it down A LOT. The end result, is a sprocket thats .4 lbs lighter, and combined with the cutouts on the internal sprockets, knocking a pound off EACH transmission.

According to our machining mentor, the sprocket will still be fine. He’s a machinist at the local nuclear power plant, so we generally try to trust him. My jaw dropped when I saw these done.

Wow looks great! Now try doing that to about 30-40 gears on the entire robot, I know we had to. Drilling holes in them also helps. But I wonder… is this for your drive train or something else…

Do I dare ask why you have 30-40 gears??? I mean how many transmissions do you have??? I remember we had a 100 tooth x .5" wide gear on our 2002 robot that started at about 15 pounds and finished about 5 pounds. But I seriously don’t know why you would need 30-40.

Wow! That’s a very thin wall section over the key. For an arm application, I would be cringing over it. For kit drive, I’d think it’s borderline. We did the same think with the kit tranny last year, and it easily saved 2+ lbs per side.

However, I’ll point you to a pic of our robot (or a part of our robot) after a slew of competitions. Beware of those thin walls!

228’s shattered arm gear

Best of luck!


Soon enough, soon enough. But I may have been exaggerating, I think it’s more towards 30 than 40, but we definitely have that many on the entire robot not just the drive base. This year we actually have allot of moving parts but everything should go fine.

Custom transmissions, such as 116’s old transmission (http://www.chiefdelphi.com/forums/papers.php?s=&action=single&paperid=205) often have 10+ gears in them alone. Combined with any gearing (or sprocketing more likely) that happens after the transmission, on arms, etc, it is quite likey to hit 30 gears/sprokets on a robot, if not more. I mean, just look at 118’s 2005 bot, “Chainzilla”.