Quote:
Originally posted by sanddrag
That's a 12T? On Matt's transmission it appears to be a 16 from this post. Did you both just go little bit different ways there?
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Sanddrag,
What we did in the first stage was make it so that you didn't need any special tools (Such as a broach for the keyway), here is the order we made the first stage (That mounts on the CIM motor) While we could have made things custom, time & money as well as available tools kept us using off the shelf parts.
Step 1:Bought a stock 16 tooth Martin gear.
Problem 1: the bore was larger than the output shaft of the CIM motor.
Solution 1: took a piece of drill rod of the proper size to fit the bore, put a slight knurl on it in the lathe, put a light coat of Green thread lock (essentially high strength epoxy) and pressed it into the gear. When Dry, we bored out the piece of drill rod to slightly under the output shaft of the CIM motor.
Step 2: Made another piece of Drill rod to fit into the new bore on the 16 tooth gear and turned the end down so that it fit the bore of the PIC design 48 tooth gear. We attached them together on this temporary shaft so they were welded together perfectly in line with each other.
Step 3: Take this new assembly of two standard gears welded to each other and turn the hub down on the PIC design gear so that it becomes the end of the shaft and fits in the bearing opposite of the CIM motor.
Step 4: Press the whole assembly onto the CIM motor with more Green LockTite. Advantage: No Setscrews, keyways or anything. Disadvantage: It isn't ever coming off for any reason.
This was how we accomplished the first stage and you can make it easily with only a lathe, welder, and small press.
Next stage of 20 tooth and 50 tooth was simply welding to shaft.
We diverged somewhat from the #45 2002 design but then we left off the Lovejoy coupling and used #25 chain drive to the tank treads (20 tooth/60 tooth) only because lack of planning dictated that we didn't know how the gearbox was going to fit in the chassis and connect up. I would have rather used all gear drive but the chain guides solved our problems. Keep in mind with all the power this had, it never broke a #25 chain. We did however go through 8 Breckoflex belts this year including 4 of the solid center ribbed belts.
I really have to hand it to Team 45 for posting the design so that others could use it either fully or as a great starting point. It is one of those things that advances the community as a whole.
With this much steel, it is imperative that you lighten each and every gear, however having this much weight down low in our chassis is what kept our stacker from falling over like many of the others even though it was over 40" tall.