Bevel Gears on Drivetrain

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Posted by Michael Quayle at 1/14/2001 10:57 PM EST


Engineer on team #253, MRT, from Mills High School.



We were considering using bevel gears on a drill motor, but the bevel gears sold by SmallParts are very small (in terms of the bore diameter). What are the advantages/disadvantages of using bevel gears on a drivetrain?

[archiver]

Posted by Ed Sparks at 1/14/2001 11:25 PM EST


Coach on team #34, The Rockets, from Bob Jones High / New Century High and DaimlerChrysler.


In Reply to: Bevel Gears on Drivetrain
Posted by Michael Quayle on 1/14/2001 10:57 PM EST:



Thers's nothing wrong with using bevel gears in a drive train.

- but -

I wouldn't use brass (Small Parts only offering)

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Posted by Matt Leese at 1/14/2001 11:54 PM EST


Other on team #73, Tigerbolt, from Edison Technical HS and Alstom & Rochester Institute of Technology.


In Reply to: Bevel Gears on Drivetrain
Posted by Michael Quayle on 1/14/2001 10:57 PM EST:



The team I was on last year (7) used bevel gears in the drive train. They ended up giving us no end of trouble. Basically, we had problems with the gears backing away from each other and then starting to destroy each other. We also made the mistake of not gearing down the drive motor at all. I think we also ended up putting a side-load on the motor because of the bevel gear which caused the drill motor itself (not the gearbox, the actual motor) to die on us several times. BTW, we were using the same bevel gears that the Dewalt right-angle drill uses (one of our sponsors was Black & Decker.....) and that didn't help us any. Can you successfully use bevel gears? Yes. Would I recommend it? No, it's more trouble then it's worth.

Matt

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Posted by ChrisH at 1/15/2001 2:26 PM EST


Engineer on team #330, Beach 'Bots, from Hope Chapel Academy and NASA JPL, J & F Machine, Raetheon, et al.


In Reply to: Bevel Gears on Drivetrain
Posted by Michael Quayle on 1/14/2001 10:57 PM EST:



: We were considering using bevel gears on a drill motor, but the bevel gears sold by SmallParts are very small (in terms of the bore diameter). What are the advantages/disadvantages of using bevel gears on a drivetrain?

For Spur gears you only have to consider radial forces. With bevel gears you get thrust forces as well. Sizing and determining tooth stresses also becomes more difficult. I highly recommend checking tooth stresses BEFORE you build the drive train. The brass gears SPI has don't carry much load. The competition environment would qualify as "severe" in most design guides.

You can use them, but just know they are alot most subtle than they look.

Christopher H Husmann, PE
Lead Engineer Manipulator Team
Team 330 the Beach 'Bots

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Posted by Joe Johnson at 1/15/2001 8:29 PM EST


Engineer on team #47, Chief Delphi, from Pontiac Central High School and Delphi Automotive Systems.


In Reply to: Bevel Gears on Drivetrain
Posted by Michael Quayle on 1/14/2001 10:57 PM EST:



Bevel gears are fantastic, if you know what you are
doing and you can spend time to get the interfaces right.

This is very ticklish business.

In general, I would never recommend a team try this
cold. If you have time in the off-season to work it
all out, go for it. In the heat of the 6 week build
without a trial run, I am not very optimistic of a good
outcome.

Just my opinion.

Joe J.

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Posted by Anton Abaya at 1/20/2001 12:30 AM EST


Coach on team #419, Rambots, from UMass Boston / BC High and NONE AT THE MOMENT! .


In Reply to: I wouldn't use them but you can if you are careful
Posted by Joe Johnson on 1/15/2001 8:29 PM EST:



we'll just use software then aye, what will the world do without us programmers...

-anton

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Posted by Ken Leung at 1/16/2001 3:02 AM EST


Student on team #192, Gunn Robotics Team, from Henry M. Gunn Senior High School.


In Reply to: Bevel Gears on Drivetrain
Posted by Michael Quayle on 1/14/2001 10:57 PM EST:



: We were considering using bevel gears on a drill motor, but the bevel gears sold by SmallParts are very small (in terms of the bore diameter). What are the advantages/disadvantages of using bevel gears on a drivetrain?

One word: Gear box.

When you want to use bevel gears, you want to build your own little gear box to support the two shaft of each gear. And I am not sure what kind of machine shop you have, but I am sure it need to be really accurate to make this setup efficent enough to work really well... We tried doing this, and we end up bending the shafts and having trouble building a good enough gear box to conserve enough power from the drill motors to have a really good drive train. Be warned.

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Posted by Rob Gordon at 1/16/2001 12:47 PM EST


Engineer on team #69, H.Y.P.E.R., from Quincy Public Schools and The Gillette Co..


In Reply to: Bevel Gears on Drivetrain
Posted by Michael Quayle on 1/14/2001 10:57 PM EST:



We utilized bevel gears last year, and had a fantastic drive train with very few problems. However, we used fairly large steel gears. We prototyped the year before using the gears from small parts and trashed them in a few minutes. I would keep your design for another year when they allow us to use gears from outside sources.