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Unread 08-05-2014, 03:02 PM
AndreaV AndreaV is offline
That girl with chips in her hair.
FRC #1360
Team Role: Mechanical
 
Join Date: Aug 2013
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Re: Andymark Churros

Quote:
Originally Posted by philso View Post
Yes, they were live axles. The drive train team may have used the churros so they would not have to wait to get the proper hex shaft material. I don't recall them having the "twizzler" problem but I can understand that it could happen. We may just be lucky.
They may have been live, but i am sure these live axles were supported by bearings on both sides, with the shaft section probably being around 3". In a butterfly drive whatever is driving the shaft is bolted directly to the wheel or driven by the hex in close proximity to the wheel. On a live axle WCD the sprocket/belt is on the opposite side so the whole axle is susceptible to torsional loading, which is the twisting action mentioned earlier.

With a WCD you have traction wheels being cantilevered, the shaft has to deal with axial and radial loading. Sure all shafts have to deal with this in some regard, but in a WCD the wheel(which is acting like a lever) transfers it directly to one side of the shaft, instead of evenly distributing it between both. This is when these forces become a problem.

I busted out my paint skills to illustrate what this looks like on a wcd with live axles.

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Last edited by AndreaV : 08-05-2014 at 03:09 PM.