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Unread 24-01-2011, 10:26
ajlapp ajlapp is offline
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AKA: Anthony Lapp
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Re: Sprockets and Wheels not Concentric?

The holes on the Plaction wheel are clearance holes. They are not designed to be used as a piloting feature.

The bearing trick mentioned will work. Another option is to design an assembly fixture. We have one made from 1/2" TGP shaft and a turned piece of aluminum. The aluminum has a shoulder which properly pilots into the bore of the sprocket, the 1/2" shaft then pilots into the bearings.....when you tighten up the bolts everything will stay positioned properly.

You can also do a pretty good job just eyeballing the alignment if you spin the wheel with a hand drill, drill press or lathe. At a few hundred RPM's you should be able to see the "wobble".

Loosen the bolts, adjust the sprocket, re-tighten and check. This can get you more than close enough for a kitbot chassis.
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