Master Gearbox's
 

There have been many gearboxes made in the FIRST building season. What gearboxes do you use and what are the pros and cons. Also one cim or two cims, fps, and reliability. This thread is created to help veteran and rookie teams. Also this helps organize all the gearboxes.

thanks

Re: Master Gearbox's
 

2 Andymark Toughboxes
2 CIMs in each
18 Tooth Output to a 22 Tooth Wheel Sprocket
~7 FPS through 6" wheels.

Our gearboxes were loud. We will probably be taking out one of them and disassembling to see if something is wrong. They have been very reliable though. They haven't broken down ever.

Re: Master Gearbox's
 

I strongly approve of AndyMark products. I used some Gen 2 shifters last year, Toughboxes this year, and I'm planning on ordering SuperShifters for an offseason project (and next year, most likely). I've never had a problem, and they've all been rock-solid. For ease of use and reliability, AndyMark is hard to beat.

As far as motors go, 2 CIMs per side is my standard. I've done it ever since they added the additional CIMs to the kit in 2005, and it's definitely the way to go.

Re: Master Gearbox's
 

For the last 2 years, we have bought the replacement parts for the Andy Mark 2 speed gearboxes and then made our own gearboxes from those. We tend to integrate the gearbox into the frame, use 2 CIMs per side, and direct drive the middle wheels of our 6 wheel drive base. We go with AM because most of the hard work hex broaching the gears and making the dog pattern is already done. And everything just works.

Off the top of my head, I would guess 6fps and 11fps.

Re: Master Gearbox's
 

330 and 1135 use AndyMark. 330 uses the Gen 2 shifter, pneumatic, while 1135 used the Toughbox last year.

330: 2 CIMs, 6WD, not sure of speed, no gearbox problems have ever taken them out of a match. (Chain problems have only done that twice in the last 6 regionals/championship.)


1135: 1CIM, 4 toughboxes, mecanum drive, too slow (our fault--I should have had the team switch the Toubox output sprocket with the wheel sprocket, or something like that.) No gearbox issues.

Pros: Unless a rule changes, guaranteed legal, very reliable, and easily repairable if you do somehow break one. Also good tech support.

Cons: A little pricey, but it's comparable to doing it yourself. So that evens out.

Re: Master Gearbox's
 

It all depends on what you are comfortable with. Team 108 and 1345 both used AndyMark Gen1 and planning on using parts from it next year as well.

Download the JVN calculator and look under the first tab called "Specs." It has all the information you would need about the motors that are supplied in the kit. It also shows specs on stall torque, stall current, and free current when you combine motors together. And of course you can easily calculate the speed of your drive train, rotary mechanism, linear mechanism, and intake mechanism as well. It's a useful tool. Download it from here.

Re: Master Gearbox's
 

Custom. You get what you want, how you want it, in what shape you want it, how fast you want it, and so on. It's more expensive, but I've found it to be worth it in the end. You end up (in my experience) with a lighter package, and you know EVERYTHING about it, so maintenance is pretty simple.

Oh, and you get the bragging rights of a custom system.


EDIT: If you have ANY kind of a budget, I can't suggest anything other than Andymark gearboxes. They're reliable, proven, light(ish), and the best bang for your buck. They're not as durable as I'd like them, but I personally prefer bulletproof (figuratively) robots.

Re: Master Gearbox's
 

In MY experience, the AndyMark products have been fantastic. I also prefer bulletproof robots, and the AndyMark gearboxes have delivered again and again.

We've bought AM stuff before, and we'll do it again. They should definitely be the first place any mechanical designer looks.

Regards,
John

Re: Master Gearbox's
 

With the same design constraints they have to deal with, I doubt many people in FIRST could build a better all around gearbox. If you're using them right, the AM gearboxes are extremely unlikely to fail. I'd be very impressed if anyone could top them.

Re: Master Gearbox's
 

AndyMark, all the way. You can use them as-is or use the internals and replacement parts as the besis for a custom design. More importantly, in my opinion, is that during that 6-week crunch, you can concentrate on designing the rest of your robot and integrate a finished product into your design (made even easier with their pre-made 3D CAD models).

Re: Master Gearbox's
 

I'm with John. AM gearboxes qualify as bulletproof in my book.

There is no better bang for your buck. End of story.

Re: Master Gearbox's
 

I've never had any problems with a properly assembled AM gearbox. We've used them this year and after 2 regionals and the Championship (37? matches or so) and a weeks worth of beatdowns we've never had a problem with them. One of them is kinda loud but it sounds cool so we never really cared. If you're ever thinking of using a custom gearbox I would look at AM first. Their products are constantly being revised and have been tested for seasons at this point.

Re: Master Gearbox's
 

We like to make our own gearboxes so we can get the exact ratios and mounting configuration we're after. However, we are still conscious of time and budget constraints and limited resources. This year we used numerous individual AndyMark gears in our drivetrain and spool gearboxes. They're cheaper than Martin gears, there are no heavy hubs, and they already have a hex broached bore (or in the case of the dog gears, are all ready to go).

Re: Master Gearbox's
 

Any pics?

Re: Master Gearbox's
 

Here is a shot of ours. Nothing too special. Some AM gears on either custom or AM axles, depends on the axle, and some laser cut 1/8 " aluminum side plates held together by spacers.

Transmission

Re: Master Gearbox's
 

Third'ed.

We only had one problem with ours this year (which I'm pretty sure is due to an assembly error), and the support we received on the product was fantastic. What other companies answer business emails at 11pm?

Re: Master Gearbox's
 

I can't stress this tool enough. The biggest thing we gained from using this tool was figuring out why we were pulling so much current on our '07 robot. To alleviate this, in '08 we used 2 CIMs per side in order to facilitate pushing through traffic along with a AM Super Shifter. 23 amps sustained per motor ('08 low gear) is ALOT better than 65 amps when pushing ('07 single speed)...

I also fourth the AM recommendation. I just found a local machine shop who may be able to do custom gearboxes for us in future years but until we reach a deal in coming months, we plan on sticking with AM shifting gearboxes. The problem we had this year was an error on our part and the AM rep in Atlanta stuck with us until we found the issue.

Great parts, even greater people.

Re: Master Gearbox's
 

I would ask that shop to make other parts for the robot you can not buy rather than gearboxes you can get from AM.

Re: Master Gearbox's
 

Or, alternatively, have them make the parts for your gearboxes that you can't get from AndyMark. If their parts fit some of your design (say, your shifting mechanism), plop those into Inventor and save your machine shop some work. Less-stressed resources are happy resources, in past experience.

Re: Master Gearbox's
 

Thats what I'm thinking for next year. Ive been comparing dewalts to a custom dog shifter and it looks like its only going to cost us about $50-75 more per transmission for a dog shifter. Which depending on how our dewalt prototype works, might be worth the price difference to go with the bulletproofness (I just made up a word) of the spur gears. We would have to modify an AM shifter for direct drive but other then that it would be perfect.

Re: Master Gearbox's
 

Thank you all for the kind words regarding AndyMark products. We realize that we are not perfect, but we are continually improving and working to provide parts that benefit FIRST teams.

That rep in Atlanta is Nick Boyce. He is a freshman at Purdue-Kokomo, in the ME Technology program. He was the mechanical student leader on the TechnoKats (team 45) during the last 2 years. Nick works mornings at AndyMark and takes classes during the rest of the day. He will also work full time this summer, helping us do various things. I believe that he likes his job.

Nick is an important part of our small team at AndyMark. Mark and I are both happy that Nick was a good service to teams at the Championships. We decided to spend time as key volunteers on the fields, and left the booth to Nick. We wondered if this was a good thing to continue to do, and hearing that Nick did a great job helps us fill these key roles (Mark as FTA on Archimedes and me as referee on Newton) to help the FRC Championship run smoothly.

Thank you again,
Andy

Re: Master Gearbox's
 

The AM tough boxes are awesome - and although some people think they are expensive, they really are a great deal if you look at making your own. Price it out... seriously.... (Go down to Crazy Andy's - their prices are INSANE!)

Making your own box has other values, like the experience of making your own. But if you are concentrating on something else.... I don't know if you can beat them.

Plus the support is very good.