Transmission HELP!!!

HI, Does anyone have a readable copy of Team 116 (Epsilon) 2003 dual motor, dual speed tranmission. I tried downloading them in the papers technical section,but half of the pictures don’t appear. :confused:

Don’t worry, it isnt just you. The file in the whitepapers section has something wrong with it. I don’t know if I have a copy on this computer, but I can get a copy to you later tonight.

[edit] I have a readable copy. It is split into three parts that I can email you, if you get me your email address.


try this link, its a pdf file of the most recent version.

Thankyou both for all your help!!! :smiley:

There is an updated version of the Team 116 dual-motor, dual-speed gearbox design white paper that corrects the problem with some of the drawings not displaying properly with some versions of MS Word (I sent Justin a copy of this version earlier today). The submission section for the White Papers section is not yet working, so in the mean time you can download it from the Team 116 web site at The file is about 1.1meg, and all the detail drawings have been broken out as .pdf files.

To anyone that is building this transmission, please note: there was a typo in the earlier version of the white paper. Part #10, “Torque Gear A” should be a 15-tooth gear (Small Parts part #B-GSS-2015). It is incorrectly listed as a 14-tooth gear. Please correct it if you have downloaded the old version of the white paper. It is corrected in this version (thanks to Stu Bloom/Team 1018 for spotting this!).


Thankyou Mr. Lavery! :smiley:

Since a few people have asked, let me also add the following note:

For this design, Part #9 (Bosch Pitch Change Gear) is indeed a 55-tooth, 0.7 module gear. This is NOT a typo. They are available from PIC Designs, and can be ordered via their web site or phone-in orders. Just request part number MSG25-55 when ordering. In our experience, the delivery time for the 55-tooth gear is exactly the same as a more common 56-tooth gear.

The 55-tooth gear was selected as the best-fit solution for the matched free-speed design point we selected for this concept. There is legitimate debate about whether a 55-tooth gear is absolutely needed, or if a more commonly available 56-tooth gear is “good enough.” If you like, you can drop in a 56-tooth gear instead. If you do, just adjust the center-to-center distance between the mounting location of the Bosch motor and the first torque shaft (Part 11) accordingly, and you should be good to go.


I have a couple of problems and need your help …
First, the file I get using the url above will not open in my version of Winzip (v8.1). Actually the download is almost instantaneous - as if I may be getting only a header. And I get the message “Cannot open file: it does not appear to be a valid archive …” when trying to open. I’ve tried downloading multiple times into different directories and under different filenames.

Second, I believe I have found another discrepancy with the prints (may or may not be corrected in the latest version… but I can’t check because I cannot open the file). During our initial build attempt we had some difficulty assembling the side plates. After checking the .500 dia hole alignments I noted a significant mis-alignment of the hole pattern between the two plates, and a more detailed inspection of the drawings identified the problem. The offset .500 dia hole has a different vertical dimension by .076 (.734 vs .810). I believe the motor-mount side is the correct dimension (.734). I will contact you off-list to provide my email address and ask for the latest copy of your white paper.

Let me see, how can I say this? Oh yeah, like this: “MicroSoft S*#@S!”

Now that I have that out of my system, I have given up on trying to get a MicroSloth-compatible version of the white paper that is generally accessible. I have re-posted a copy of the entire document as a compressed (.ZIP) .PDF file on the Team 116 server at

If for any reason that doesn’t work, there is another .ZIPped version of the .PDF files at compressed using a different tool.

These archives are ENTIRELY .PDF files, so hopefully no more MicroShaft document compatibility problems (keeping my fingers crossed!). The archive takes a little more space, but it should still work.

Regarding the hole alignments on the side plates, I really am not sure what you are refering to. I just went over the drawings of the side plates again to be sure, and the offset distances of all the holes are the same as far as I can tell. I see the 0.734" dimentsion, but am not seeing a 0.810" dimension anywhere on the print for either Part 1 or Part 2 (we are talking about those parts, yes?).


/edit I just went back and checked. There is a 0.810" dimension on a intermediate-development version of the design that we did last summer while updating the design to accomodate the new Bosch motors. Could you have somehow downloaded an obsolete version of the drawings? The URL above should point to the correct/current version - if you have any prior versions please throw them away and make sure you have the one referenced above. In the mean time, have I mentioned the problems I am having with MuckroSoft? edit/

I ordered some 0.7 module gears over the summer from PIC, not the 55 tooth gear. The delivery time was at least three weeks. I would suggest for those people using 0.7 module gears to get their orders in now if they want to have the parts by the end of the build phase.

I may have had an odd part (48 tooth and 52 tooth). But, better safe than sorry.

We have decided to use this design this year, and fortunately the supplier you mention is right in our own backyard… But we still had a very considerable lead time until one of our engineers talked to the guy on the shop floor at PIC and sweet talked his way into making them push our job ahead of some others because of our situation! Hehehehe!

OK, for all the teams that DON’T receive your gears from PIC until AFTER the ship date, now you know why! :smiley:

Elgin - can you just have your engineer sweet-talk PIC into just running off 37 dozen of the gears all at once, and shipping them out to the teams that have ordered them?


Whats interesting is that we ordered 4 of those gears from PIC on the 25 of January and we were told that we’d have them by the 22 of February. Now we couldn’t wait that long so my Mom called PIC every day after the order and spoke to the productions supervisor, and he finally got tired of it so he said that we’d get them by the 5th of February and WE DID!!! GO MOM!!
Parents always seem to save the day, :slight_smile:

Wow Dave, this tranny design and especially this gear seems like a pretty popular item this year.

Any possibility of including it in the kit next year (the gear, that is)??? :smiley:

And I don’t know much about gears, but why is this particular one so rare as to only seem to be made by one company?? Or, is that just an ignorant assumption on my part??

Can we borrow your Mom? :slight_smile:

As far as I know, PIC Designs seem to be the only U.S. vendor for off-the-shelf 0.7 module metric gears. I presume that the demand for them is so low that it is just not worth it for other vendors to keep them around taking up space.

What I will do is recommend to FIRST and to PIC Designs that, if we have the Bosch motors in the kits again next year, PIC be notified in advance so they can build up some stock and have them ready to ship out in less than four weeks. Alternatively, if teams indicate that they want to build on this design (or any reasonably close variant) again next year, I can work with my team to buy up a stock of them in the fall to distribute to any teams that want to use the design.

But for any of that to be worth the effort, I want to ask one thing in return from anyone that is using the Team 116 gearbox design this year: we want to hear back from you! Please provide any feedback, constuctive criticism, comments, etc. that you may have. We set out to develop a gearbox design so that teams without full-blown machining capabilities could have a dual-motor, dual-speed shifting solution if they wanted one. We know that some teams used the design last year, and from this (and similar) threads, it seems that more are using it this year. That’s great! That’s why we published it. But we would really like to hear back about how well it worked for you (particularly once the competition season starts), and your comments. Intentionally, we left a lot of room for improvement! The thing we really want to see is the team that takes this design, comes up with the next generation version, and publishes it back into the FIRST community. In other words, use this as a starting point, improve it, and let everyone know!


I don’t know how high the demand for 0.7 module gears is (the demand might be higher if they were more readily available) but I suppose someone with a wire EDM machine could make a few bucks (few meaning a lot) if they made these.

Also I was wondering, can a laser machine cut gears?

It depends on how thick you want them. If you want a really fine face width, (like < 0.060") then certainly. If you want more like 0.50", then you might be better off with using a water jet or better yet EDM. The material used makes a big difference too.

If Nylon will do, you could use Selective Laser Sintering (SLS) to make a gear from powder as opposed to cutting one from stock. I’m planning to try this for some encoder gears as they will be lightly loaded and the consequences of failure are small. But then I’m getting paid to try new things with our SLS machine at work and a working gear will be something new for us! :smiley:

SLS can be used for metal too, but that is a lot trickier and to get a good surface you will need a finish pass with a machine anyway. By the time you get it all set up you would probably be better off cutting one from stock.