Best Dual Speed Shifters?

[JFKinator]

My team wants to use a dual speed shifter for next year but we can't decide on which shifter we want, due to the lack of experience in using a transmission. I've narrowed it down to three candidates; WCP DS, Vex Pro Ball Shifter, and AndyMark Super Shifter.

More info on our drive train, it will be a 6WD trank drive. Please comment with any useful info or feedback you have, thanks!

[Gregor]

Weight-Ball Shifter
Price-Ball Shifter
More Ratio Options-Super Shifter
Ability to servo shift (although not recommended)-Super Shifter
Ease of integrating into a WCD-WCP Shifter

Note that Andymark will be releasing a new shifting gearbox post championships.

[Justin Shelley]

I want to look into using a transmission also next year but I am looking to modify whatever one we get to have a three speed transmission. One-High Torque pushing. Two-Driving. Three-Racing

[midway78224]

My team has always use the Super Shifters. I love them. If you gear them up right they can give the speed and power you look for. Its a little heavier then some of the other option so if weight is the issue then ill look into the vexpro ball shifters. I would also recommend the pneumatic shifter with the super shifter from AM. That is just my opinion though. If you have any more questions on our set up feel free to send me a pm and ill answer any questions you may have.

[orangemoore]

I just want to point out that Andymark is going to release a new shifting gear box near the end of the month.

[midway78224]

Originally Posted by orangemoore

I just want to point out that Andymark is going to release a new shifting gear box near the end of the month.

Wow. I would love to see what they come up with. I really love their super shifters. I have used them since they first came out with the Gen1 all the way up to the Super Shifter edition.

[Garrett.d.w]

For my team's applications, the AM Supershifter is the way to go. The gears are beefy, there are many gear ratios to choose from, and they fit nicely in our WCD design. For us, they have also been reliable. One of them is three hard seasons old and still works like it just came out of the box.

Also, having taken them apart for seasonal maintenance, the mechanism is robust and easily serviced with a hammer and basic tools

If you are looking at getting a set of transmissions for your team, define your goals while using them and make your decision that way. Each team is different and will prefer a different type of transmission for their typical drive train.

[JFKinator]

I guess another question I could ask is if any of these shifters would be able to work with a PTO or be able to be modified to do so?

[rahilm]

Originally Posted by JFKinator

I guess another question I could ask is if any of these shifters would be able to work with a PTO or be able to be modified to do so?

They would be able to with custom made plates (or maybe you could put two in series, where the output from one is chain driven the second where the input is the output shaft; this would require lots of swapping gears, not sure if the gears are available to make it feasible). Out of the box, though, no, they cannot.

[Garrett.d.w]

Originally Posted by JFKinator

I guess another question I could ask is if any of these shifters would be able to work with a PTO or be able to be modified to do so?

in 2010 The team made a PTO with a supershifter (the main reason why they bought it was to have the same set of motors that powered the kicker also power the lifting mechanism). I don't know how they did it, but I know they did it without modifying any of the plates. I could shoot Nathan an email if people are curious.

[pmangels17]

This year we modified a Super Shifter to make a PTO. WHen we were done, it was nothing like the Super Shifter. We changed a lot of the ratios, worked in an extra CIM, changed the final stage ratio, and added a brake. Basically it was an easy package from which to get a lot of gears. Our final PTO product was absolutely nothing like the original Super Shifter, going through three iterations in CAD and two in real production. Also, we made some shafts coaxial using idler gears and bearings.

[thefro526]

Originally Posted by JFKinator

I guess another question I could ask is if any of these shifters would be able to work with a PTO or be able to be modified to do so?

Modifying any of the COTS shifting gearboxes into a PTO is relatively straightforward depending on what you're shooting for. This year, 341's gearboxes are nothing more than a WCP SS shifting stage* repackaged into a custom box.

Basically what you're doing is taking the shifting stage from any of the shifting transmissions, putting it inline/parallel with the transmission for the drive, and then engaging/disengaging that shifting portion as you need to transmit power to whatever mechanism. In our application, we have three CIM motors each with a 12T Pinion driving a 72T gear for a 6:1 total reduction. The output of this shaft then drives one of our drive wheels with through a series of 50T gears for a 1:1 reduction (can be changed by swapping gears). On that same output shaft, there is a 60T gear that drives a 60T Dog Gear that is the same as used in the WCP SS Gearbox. The 60T Dog gear is on a standard WCP SS output shaft - but instead of the output shaft having two different gears on it (high and low, usually a 60T and 45T) there's just the 60T and a brake. Basically, when the 60T gear isn't engaged, the PTO shaft is locked, but when the PTO is engaged, the PTO shaft is essentially a mirror of the drive output shaft.

If you wanted to do a two-speed transmission with a PTO, it's more or less the same as what I described above, although, you'll have two shifting stages. If you wanted to, you could have the CIM's drive a cluster shaft that drove both shifting stages and then devote one to the drive and other to the power take off... Or you could drive a second shifting stage off of the primary shifting stage and do some neat tricks like having a PTO output with a high and low gear - this lets you drive a mechanism at two different rates, high speed for extension, low speed for retraction and stuff like that.

One thing to keep in mind when designing a PTO for whatever mechanism is whether or not some portion of it will need to be able to be put into neutral and/or held into position. A lot of PTO's will have some function that will allow the drive to be put into neutral to keep the wheels from spinning while the PTO is engaged, but it isn't always necessary. An 'easy' way to add a neutral function into a standard PTO setup (or two speed, if you wanted) is to replace the standard two-position piston with a three-position piston. The third position should land somewhere between the extended and retracted position of the piston which would then allow your transmission to go into a configuration where neither high or low gear is engaged.

* Shifting stage being the shaft that has the shifting hardware, whether that be dog gears, balls, etc. Remember that a shifting shaft can have two different gears on it to shift between ratios, one gear and nothing for an engaged and disengaged setup, or any other combinations of brakes/gears/nothing.

[Crazyboy]

We have them on 1334's 6-wheel chassis, they work pretty well, no issues. The team I was on last year used Supershifters, and they also worked pretty well with a 4-wheel drivetrain. Benefit of the Supershifters is that they *can* use servos, we had some success with them, you just have to be super careful in terms of programming/building so they don't break. To be honest though, I'd have to give the edge to the Supershifters in terms of ease of assembly.