Re: CIM-U-LATORS
 

It's not COTS until it is a component on your shelf.

During the course of my day job I occasionally run into components that exist in a catalog, but when we try to buy them we discover they don't actually exist. If I was willing to buy 1000 of them the company would pull out the tooling and make some, but they won't do it for the 3 I might need. Consequentially, I have to source and commit to COTS early or plan to go around. The Banebots situation is just an extension of the real world.

Stock Drive Products anyone? I notice that they have this 10 tooth and this 27 tooth which might be useful if they were about .7708 apart. It also seems that the 10 tooth has a bore just under 5mm. Hmmm...

Re: CIM-U-LATORS
 

With no shoes on a gravel road !

In the dark...

Re: CIM-U-LATORS
 

I stand corrected on their confiuration, I missed that they are 2.7:1 Spur gears. You're right about leaving space around them, we hadn't thought about that .... we were just assuming they'll fit in the same space as a CIM. We should be fine, though.

Re: CIM-U-LATORS
 

Normally I would agree with you about buying your own gears and making your own gearboxes, but there are many many teams that don't have that capability, either in people, machining or sponsors. I hope this Banebot problem spurs people to get out and learn more about gears, motors, etc. I know we are planning on experimenting this fall.

But the fact remains that FIRST put out 4 Banebot motors while limiting the other motors. No pinion gears, no gearboxes. Most people are going to go to the Banebot web site and expect to order from there and expect to get their order in a reasonable amount of time.

The FIRST deadline is hard and fast. Learning how to design and build your first gearbox isn't something you want to do during the build season.

Re: CIM-U-LATORS
 

FYI.
Yesterday (2/2) we received P60's ordered on 1/18

Re: CIM-U-LATORS
 

Sorry for my words, but this is a load of crap.

You have a group of people interested in engineering and dedicated to a goal. If you guys can't sit down, and decide to learn how to make a simple spur gearbox with the tools you have available, stop competing, because you either have no competitive drive.

Making a single speed, speed reducing, torque increasing plain jane gearbox is a darn simple design exercise, and if a group of intelligent, passionate and motivated people can't do it, it's just a lack of wanting it bad enough. Doing one that can be "machined" by hand is a tad bit more difficult, but only marginally so. I know of several teams who have literally hand made gearboxes (we do it quite often prototyping...).

I don't mean to be cocky, as I'm no amazing designer, but I could knock out a N:1 single speed gearbox in thirty minutes or less in CAD, and a few minutes or less in conceptual design. This is true of many, many members on FIRST teams, many of which have no special skills and are just average people.



In summary, you can do it, and if you need help just ask.

Re: CIM-U-LATORS
 

Sorry to be unclear, we ordered p60s.

Re: CIM-U-LATORS
 

I dunno Adam, you're screaming a knowledge paradox. It takes a lot of time to learn something new if you have no prior knowledge. It's very disheartening to try to learn it, produce something from what's learned, and have the product fail in use regardless of the effort put in. Lessons may be learned in the process, but those future lessons sure aren't helping anyone now.

On the other hand, after weening ourselves off of always-COTS options for gearboxes, I will say that the lessons are invaluable to the future of the team. Yet it's easy for me to say that because I have essentially had 6 tries to get things right as a mentor whereas many students only have 2-3 (or in the case of most rookies, less than 1 -- at which point mentor recruitment is critical, but not always possible).

Re: CIM-U-LATORS
 

Adam is right. Last year I made a simple 1:5 gearbox using a few pieces of Delrin, some vex standoffs, and gears from an FP Trans in about an hour or two and did most of the work using a hand drill and drill press. I ran the delrin side plates on the mill just to get a decent looking edge, but I did the rough cuts on a bad saw. I'd imagine that most teams have access to a Drill press and Bandsaw or similar tools. It's really not that difficult to make a simple gearbox, especially if you have a basic understanding of gears and how they work.

Re: CIM-U-LATORS
 

If you are looking for 16:1 gearboxes for low power operations, there are some older Banebots 36mm gearboxes in their closeout section. They come with a 385 motor which is illegal for FRC, but the 395 mounts just fine to them if you trim the 395 shaft length and swap the pinion over to the 395. They are cheap and ship next day. Not as rugged as a P60, but we've used them on past robots without a problem.

Re: CIM-U-LATORS
 

For those waiting, IMHO they are worth it. Here are some pics:





Total weight with motor 20.9 ounces.

Re: CIM-U-LATORS
 

Uh... We should open source that and get teams with CNC or sponsors with CNCs to the work... ;)

Re: CIM-U-LATORS
 

Man, if I had known the gearbox was that simple I would have just made it myself.

Re: CIM-U-LATORS
 

Wow, those are simple.

Ours are sitting just across the border waiting for pickup.

-Nick

Re: CIM-U-LATORS
 

The online description made me picture something pretty similar to that.