Evo Shifter experiences after a full season

Hey CD,

After using the AndyMark Sonic Shifters this past season with no failures, we are pleased by them. However, I am trying to see how reliable / how much better AM’s new gearboxes are to see if we could take advantage of the slightly better form and weight factors they offer.

At the beginning of the season there seemed to be some issues with their Evo Shifters, so I am seeking data from teams that used it and how they felt about having to fix their drive boxes mid season, and if they would run them again next year.

Any info is helpful and appreciated, thanks!

Team 291 used EVOs this year. We put a lot of miles on them both on our competition bot and our practice robot.

TL;DR: I would recommend them, but watch out for a few things; they take quite a bit of maintenance.

We had our comp bot driving and practicing by week 3 with them. We put a lot of miles on preseason both in driver training and at a week zero event with no problems. The first inkling of trouble came when we got into a pushing match with 4027 at a week zero event (we both had EVOs at the same ratio). 4027 snapped a dog. After Andymark sent the new dogs, the robot was already bagged, so we didn’t have time to change them. In our second match at our first regional our dog broke :mad:. We would have been toast if we hadn’t brought our practice robot’s gearboxes.

If a dog breaks, you will not have time to fix it unless you can swap the whole gearbox. It takes a while to fix it.

That should (hopefully) be fixed with the new gears. I drove the crap out of them for another 4 competitions with no problems.

Another smaller maintenance thing: The set screw on the dog came loose twice for us. Just make sure it stays nice and tight.

The setscrew on the encoder gear also came loose more than five times causing the encoder not to read correctly.

The open design, while it saves weight, requires some sort of custom grease containment. We used thin lexan. I know other teams used duct tape.

The return to default ratio at loss of pressure feature is really nice! It saved us in several matches when we lost pressure.

Overall I am happy with them; strong and mostly reliable.

Thanks for the info, one thing I am still unsure of is how you can mount them on a West Coast Drive. I made a thread about this earlier this year, and never really got a satisfactory solution. In my CAD I ended up making a whole new plate for the gearbox that moves the mounting holes, but that seems really odd to me that a new to 2017 gearbox is this hard to mount, I feel like im missing something. How did you go about mounting your EVO’s?

Edit: I see 291 used the kitbot, which I heard the Evo just drops right into… hm.

We mounted ours as shown here.

I’ll echo what the poster from 291 said. We also had a dog screw back out during practice, before we started using Loctite on them. We never broke a dog, likely because we replaced the original ones with AM upgrade parts as soon as those were available.

We do recommend protecting against carpet debris entering from the sides and bottom – for that, we used thin clear plastic that can be seen in the linked picture.

Our competition 'bot has 103 Steamworks matches on it (5 regular season events, 2 off-season events) with no EVO failures.

Hi Brian!

I was fortunate enough to be the project lead for the EVO Shifter gearboxes. My team also used them this season for 89 matches so far. 3940 did experience the shoulder screws loosening over time; a little drop of semi-permanent thread locker stopped this. We also performed the dog swap (once all other teams had received their replacement dogs,) during one of our unbag periods, and found the most time consuming part for us was the removal of the gearboxes from our (cramped) robot, not the dog swap itself. We followed these steps to replace the dogs in this video.

We ran them without any debris shielding through the entire season, and did not have any significant issues with foriegn debris damaging the gearboxes. We kept them greased with Red Tacky Grease and did not experience any issues with wear and tear on the gearbox. We actually found that we collected far more debris on the gears between the wheels of our drivetrain, than we did inside the EVO Shifters. The steel gears are pretty tolerant to soft debris, but there is certainly nothing wrong with running plastic shields like many teams did. Had we run them any closer to the ground than we did, I think we would have considered guards more seriously.

We kept an eye on them, but these shifting transmissions have required the least amount of maintenance that I’ve experienced so far.

Be careful to make sure that the splits in the 60T Encoder Gear and the collar clamp are lined up. If these are not lined up, it is easier for the screw in the collar clamp to loosen much faster.

Brian, if you have any more questions, feel free to ask them here, or drop us a note at support (at) andymark (dot) com.