Dewalt transmissions

[Fritztopher]

We used the dewalts with the small CIMs this year (based on the NBD white paper), and we never got them to work right. We had major problems with the sun gear at first, and we actually cracked one while modifying it. Then we couldn't get them to mount properly on the robot, and we ran into problems shifting. It might have worked if we had had enough time to get them to work, so I would definitely recommend tinkering with them in the off-season before deciding to use them on your robot. Given the time it took to get them to work halfway, we will not be using them again.

[fimmel]

team 885 is trying them now for next year......we havet got them yet (backorder) but i hope all goes well
/forest

[Jack Jones]

Originally Posted by Fritztopher

... We had major problems with the sun gear at first, and we actually cracked one while modifying it ....

A common malfunction, so I hear, even for veteran teams.

This design is one way to do away with removing the planet axis pins, drilling the sun gear, and pressing the top-hat onto the CIM shaft. No press fits are necessary. The adapter slides onto the CIM's shaft, and the four holes slide onto the planet pins. We (1213) water cut ours from 0.25" stainless, which is how we can leave the key in the center hole. But they could be cut from carbon steel, drilled, and notched to accept a piece of key stock. We ran them at all four corners for over 150 matches and many many hours of practice without any problems.

[woody]

We used the dewalts this year and were quite pleased with them. We only noticed two minor difficulties, both of which were at least partially our fault:
1. The yellow case MUST remain on the transmission. If its not there, the plastic shifter piece expands and can pretty much render the transmission useless. It always helps to read the directions : )
2. The mounting plate for the shifter servo needs to be fairly rigid. We ended up using some .030 or similar aluminum and bent flanges along the edges to strengthen it a bit.
Overall they are pretty reliable and you cant beat the light weight. Plus they're not too terrible to modify for use with CIM's.

[ebmonon36]

I also can give nothing but praise for the Dewalt transmissions with the CIM motors. Over the last 2 years that 1018 has used them, I don't recall any major problems with them. The only thing that I recall ever going wrong was the left hand screw on the end not being tight, but that has nothing to do with the transmission itself. Once the servos were programmed, shifting was very easy to do. This has been a very reliable drive train, and I would highly recommend it.

ERic

[JagWire]

I also would have to chime in that the DeWalts are awesome. my team had a little trouble with machining the sun gear if i recall correctly, since they are rather hard, but we got it done. the only other issue we had was when we pressed the sun gear onto the CIM, on one of our motors we ended up pushing the shaft in the CIM and fractured the armature. not exactly a cheap mistake, but we lived.

once they were put together and everything was programed they were awesome. we were a rookie team last year, and, thanks to a lot of great expertise on board we didn't have a whole lot of trouble with them. i'm quite sure we'll be using them again this year also in all likelihood.

[newton418]

Team 418 has used the DeWalt CIM combination for two years now with great success. The transmissions themselves are very reliable IF you build them correctly. You can follow the whitepaper word for word and get a working transmission or you can made specific modifications if you have the experience to understand how everything works. I wouldn't recommend tryint improve the whitepaper if it's your first time working with these, the whitepaper is tried and true.

Another note, if you are using a small #25 chain sprocket with the DeWalt transmissions, make sure your alignment is dead on and your chains are well tensioned. We used a 14 tooth sprocket and on occasion we would throw a chain. Luckily, we managed to fix the problem in the pits, but just a word for the wise.

Also, the McMaster-Carr clamp collars are sufficiently strong to hold any DeWalt-motor assembly. Some of the members on our team were scheptical, so I attached the motors and jerked them around, way more than would happen in competition, and they didn't move at all.

If you want to see how we used them, here are a couple pictures:
http://www.lasarobotics.org/gallery/...T_06_6wk_e0007
http://www.lasarobotics.org/gallery/...T_06_6wk_e0012

[Robots_R_Us]

So where does one find these DeWalt transmissions economically?

Thanks

RRU

[Gabe]

DeWalt service net. You do have to create an account but after that it is easy. By the way, the total cost (minus shipping) is a little over $70 dollars from their updated price list. The DeWalt service net exists so that people can order replacement parts when their tools happen to break somewhere.

[Stu Bloom]

See my earlier post here for some good information on these transmissions, INCLUDING our source for complete drills for the past couple of years. It has been my experience (as noted in that referenced post) that many of the required parts are back-ordered on the Dewalt service website.

[Gabe]

Originally Posted by Stu Bloom

See my earlier post here for some good information on these transmissions, INCLUDING our source for complete drills for the past couple of years. It has been my experience (as noted in that referenced post) that many of the required parts are back-ordered on the Dewalt service website.

Actually, they are only backordered nearing the beginning of build season, which makes sense if you think about it.