DeWalt Transmission questions

[Stephen.Yanczura]

Originally Posted by StevenB

The chuck/gearbox shaft isn't threaded, correct? I attempted the long lever trick this morning, and broke a Craftsman ratchet. I'll have to try again with a regular wrench or a stronger ratchet.
What size wheels are you using? Do you have any other gearing? What speed does this make the robot go?
We have thought about this, as it would elimate a lot of weight, as well as some of the problems with chain and sprockets.

While your at Sears exchanging that busted ratchet for a free new one (<3 craftsman) pick up a breaker bar. When your putting a huge lever arm on a ratchet, you're really concentrating all that force on the little pin or ball inside that makes the **click-click-click** when you rotate the tool. To a point this is okay, but if you over do it you kill the ratchet. Breaker bars have no such parts and will not break quite so easily.

I have a 36" Craftsman 1/2" BB, and a can of PB Blaster that *always* works

Good luck

[AJ R]

I searched through the threads a bit and couldn't find anything on this, so I decided to post it here. Our team is also working on using the 3 speed dewalts for our robot next season. The only thing we are concerned about is if the transmissions are shift on the fly or not. Some of the mentors are really questioning this because of noises we hear between 2nd and 3rd gear. How often can these be shifted while in while in motion? If any, what problems have occurered and what should we do to prevent the problems?

[woody]

Originally Posted by AJ R

I searched through the threads a bit and couldn't find anything on this, so I decided to post it here. Our team is also working on using the 3 speed dewalts for our robot next season. The only thing we are concerned about is if the transmissions are shift on the fly or not. Some of the mentors are really questioning this because of noises we hear between 2nd and 3rd gear. How often can these be shifted while in while in motion? If any, what problems have occurered and what should we do to prevent the problems?

We used the DeWalt trannies with CIM motors last year and had no major problems. They will shift on the fly as many times as you want them to. Those noises you hear are normal and shouldnt cause you any problems. The only mistake we made was that, initially, we didn't replace the case, which allowed the plastic ring that actually does the shifting to expand and warp. So just make sure that you replace the front section of the drill case to avoid this. Good luck!

[StevenB]

Getting the chuck off was easy, once I had the right tools, and was turning the right way! Attached is a pic of the tool I used.
Another question: For those of you who didn't use the third stage, what wheel size and sprocket ratio did you use? We're planning on using an 8 inch wheel, which I think will require approximately a 60 tooth sprocket. Is this correct?

[Stephen.Yanczura]

Originally Posted by StevenB

Getting the chuck off was easy, once I had the right tools, and was turning the right way! Attached is a pic of the tool I used.
Another question: For those of you who didn't use the third stage, what wheel size and sprocket ratio did you use? We're planning on using an 8 inch wheel, which I think will require approximately a 60 tooth sprocket. Is this correct?

Breaker Bar FTW

[StevenB]

We've now made the sun gear adapters and built a test drivetrain with 2 DeWalt/CIMs. The adapter works great, except that I didn't account for the small indent in the center of the back of the sun gear. This allowed the gear and adapter to slide up the shaft ~1/8, to the point where it would shift all the way into 3rd gear reliably. A couple of small washers to fill in the indent solved the problem.
I'm now working on shifting software. Are there tricks to making it work optimally? Joe P. mentions the neutral zone and "Software syncronization" - how does this work?
Thanks!

[MikeZ]

Originally Posted by StevenB

We've now made the sun gear adapters and built a test drivetrain with 2 DeWalt/CIMs. The adapter works great, except that I didn't account for the small indent in the center of the back of the sun gear. This allowed the gear and adapter to slide up the shaft ~1/8, to the point where it would shift all the way into 3rd gear reliably. A couple of small washers to fill in the indent solved the problem.
I'm now working on shifting software. Are there tricks to making it work optimally? Joe P. mentions the neutral zone and "Software syncronization" - how does this work?
Thanks!

I am curious on how the teams that are not boring out the sun gear but rather using adapters to fit to the sun gear are dealing with the additonal distance (hieght of sun gear) that the transmisison is from the CIM. Do you build a custom case that fits over the transmission and connects to the CIM? Do you build a wider CIM plate and still use the yellow clamshell? Do you cut down the CIM shaft? Thanks

[StevenB]

I am curious on how the teams that are not boring out the sun gear but rather using adapters to fit to the sun gear are dealing with the additonal distance (hieght of sun gear) that the transmisison is from the CIM.

We just cut the clamshell ~3/4 of an inch farther back. The same adapter plate worked, after we cut some small grooves into the side of the clamshell for the screws.