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Topic: One problem with direct drive :-).

It finally happened last night: The Y rod slid sideways for some reason and the oldham shaft coupler wasn't coupled anymore (making it kind of difficult to move in the Y direction).

It has run for many hours with no problems, so I'm not sure what made it decide to shift last night, but if it keeps happening, I guess the next step will be to improvise some sort of thrust bearing for the other end of the rod to make sure it can't drift sideways.

2 (edited by jagowilson 2015-01-08 15:43:34)

Re: One problem with direct drive :-).

If you replace the side bushings in the frame with some of those flanged bearings, it'd be so tight I'd be amazed if it could drift. Just a thought. Since that's a new rod, you can get those bearings on easy... My SD rod won't fit them at all though.

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Re: One problem with direct drive :-).

jagowilson wrote:

If you replace the side bushings in the frame with some of those flanged bearings, it'd be so tight I'd be amazed if it could drift. Just a thought. Since that's a new rod, you can get those bearings on easy... My SD rod won't fit them at all though.

Depends on the bearings. The one I bought from boca bearings I had to spend a week sanding in bits of spare time to get it on the shaft at all, the one I bought from misumi simply slid right on the shaft with no real resistance (though both were supposedly 6mm holes :-).

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Re: One problem with direct drive :-).

Or you could print something like this that is the correct dimensions.  This is two halves that are just glued together with acetone so I didn't have to pull the rod loose.  It works amazingly well the picture is with it in motion so I apologize for the quality.  It is important to design in a shoulder that rides on the inner race of the bearing.
 

http://i.imgur.com/Bg5wxWa.jpg

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