NED HELP ON BUILDING 1 OR 2 SPEED GEARBOX

[EricH]

Originally Posted by gburlison

This gearbox has a 16 to 1 ratio using 5 tooth stem pinion gears on the CIMs and a 80 tooth spur gear on the output shaft. The use of a stem pinion gear requires a coupler since it is too small to fit on a CIM shaft.

Makes more sense. Is that one of yours, or did you just analyze it to death?

Edit: Yes, it is 662's 2007 robot. The discussion and original picture are here.
Edit2: Did you guys run into any issues? How much did it cost? What other info would help this team?

[gburlison]

Originally Posted by EricH

Makes more sense. Is that one of yours, or did you just analyze it to death?

Edit: Yes, it is 662's 2007 robot. The discussion and original picture are here.
Edit2: Did you guys run into any issues? How much did it cost? What other info would help this team?

Team2061 sent me a PM and I provided him more details, but the short answer is that it cost about $100. It is a simple one stage gearbox using the smallest stem pinions we could find (5 tooth) and the biggest spur gear practical (80 tooth). There is one main issue with this gearbox and that is alignment. The output shaft is supported in three bearings, so misalignment can cause binding. The first year we built this design, we used solid couplers on the CIMs and this also suffered from misalignment and binding. The Lovejoy Couplers took care of any possible binding of the stem pinion gears. Just for reference, this is our first Gen of this Gearbox. http://www.chiefdelphi.com/media/photos/19829

[=Martin=Taylor=]

Originally Posted by team2061

I NEED HELP ON HOW TO BUILD A VERY EASY SIMPLE AND CHEAP GEARBOX FOR 2 CIM MOTORS. THEY CAN EITHER BE 1 OR 2 SPEED GEARBOXES W/ PNEUMATICS SHIFTER.PLEEEEEEEEEEEAAAAAASEEEEEEEEEE HELP.

Don't forget about the Dewalt shifting drill gearboxes. They're a lot cheaper than the AM shifters, and you can get three gears instead of two or one.

They are however... a little more fragile...

Also, if you just want a 1 speed why not use modified banebots? Or whatever else they give us next year?

[DonRotolo]

Some general advice from another team of PI-O-Neers:

I think 2-speed shifting gearboxes are cool, BUT unless there was a real need for them to excel at a particular game, I'd rather put my efforts and money into something else.

Resist the temptation to build a cool robot that doesn't do anything well.

Don

[team2061]

Originally Posted by Don Rotolo

Some general advice from another team of PI-O-Neers:

I think 2-speed shifting gearboxes are cool, BUT unless there was a real need for them to excel at a particular game, I'd rather put my efforts and money into something else.

Resist the temptation to build a cool robot that doesn't do anything well.

Don

You have a really good point, i think were are going to go with a 1 speed gearbox from andymark as oppose to making one. Thank You very much PI-O-Neer.
P.S I didnt think there was another team named pioneers in FRC. This is going to be our 2nd season

[Lil' Lavery]

Team 116 has posted designs of their 2002-2004 era 2-speed, crash shifter. While this specific design is now outdated (Bosch drill motor not included in 2005-2007 KoP), variants of this design are still used (379's 2007 shifter was based on this, as well as several other "descendants" of this transmission).
http://www.chiefdelphi.com/media/papers/1437
In 2007, Team 116 used the AndyMark gen.2 shifters.