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Unread 29-12-2015, 19:33
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Nate Laverdure Nate Laverdure is offline
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Re: pic: Chain and Wheel in Tube

Quote:
Originally Posted by MichaelBick View Post
dead axles
Quote:
Originally Posted by EricH View Post
Bolt sprocket to wheel
Quote:
Originally Posted by GeeTwo View Post
dead axle
I encourage those advocating for dead axles to play with this design and see if you can make it work. Matt has already posted the CAD for you to work from.

In FRC context, dead axle design involves transmitting torque directly from the sprocket to the wheel, without passing any torque to the axle. In this case, you would need to package both a bearing and a torque transmission feature into the 16t (or 17t) sprocket. I'm just not sure it's possible to package all that in such a small space.

BEARING
To save space, I would probably want to bore the sprocket to fit a needle roller bearing. In a high-risk application like a drivetrain, I wouldn't want to have needle roller bearings running on anything but precision ground steel shafting, which means that I can't use a bolt as the dead axle. In doing this, I have modified the 16t sprocket out of its COTS condition; this is a big deal for 2363 for various reasons.

TORQUE TRANSMISSION FEATURE
Maybe some custom bolt pattern will do this? You can't fit the 1.875" BC here. I don't think you can fit any part of the versakey system here. In making this torque transmission feature, I have probably created a custom wheel hub and may have even modified the wheel out of its COTS condition.

On top of all this, joining the sprockets to the wheels will require a bigger pocket in one of the walls of the tube, weakening the structure further.

TLDR: The precision machining requirements for this live axle design are WAY lighter than any comparable dead axle design that I can think of.
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