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Unread 14-05-2008, 17:25
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AKA: Cory McBride
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Re: CIM direct drive

Quote:
Originally Posted by AustinSchuh View Post
NOTE: I am not completely sure this will work. We did something similar and didn't notice a problem, but you never know. Maybe somebody with more knowledge can help me.

In 2006, we took an ANSI sprocket and wrapped the CIM shaft with some tin to make it close enough to the same size as the ID of the sprocket so the sprocket would spin fairly true when mounted. We then used the setscrew to hold the sprocket on. The sprocket definitely wobbled when we turned the CIM on, but the number 25 chain never fell off. So it works, but is not a very elegant solution. Thinking back on it, another way would be to take a sprocket with a smaller hole, like a 5/16" bore sprocket, and then bore it out to the size of the CIM shaft. Then, run the set screw into the keyway of the CIM. I am pretty certain that the CIM doesn't produce enough torque to make the setscrew fail. Does someone else know if that is true?
we had a heck of a time keeping our pinions in place this year. Due to having 2 gears on one CIM shaft we had no room to use retaining clips like we usually do and we had to rely on a setscrew to keep the gear from moving. Even with 2 set screws 90* from each other the gears would slide out and eventually maul themselves on the adjacent gear. We had to resort to green loctiting them, which didn't work well either when we didn't let it set for 24 hours.

Furthermore the only way to release the loctite is heat. I melted a bit off one of our Delrin sideplates the other day trying to break a stubborn one free.

We hate setscrews and figured this was probably one application where they might be OK. Lesson learned-never again will we rely on them.
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