[davidpretorius]

I have been racking my brain working out whether to go with thread around radius as others have mentioned (asimov most recently) or with the setup pictured down the bottom of this post.

So I thought why not ask Mel Bartels who seems to be a demi god in this area. So here it is.............

Thanks Mel,<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o:p></o:p>

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I really appreciate your quick response.<o:p></o:p>

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I think I know where I was getting confused. I was thinking the whole piece of equipment after the reducer was termed a roller drive that had special gear reduction. It was only after thinking for a while that it hit me that the diameter of the shaft versus the diameter of the wood circle is what gives you the extra 24:1 reduction.<o:p></o:p>

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Yes all I need is: a stepper, a 100:1 reducer, two pedestal bearings a shaft.<o:p></o:p>

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Thanks again for your advice and your great website!!!<o:p></o:p>

<o:p></o:p>

David Pretorius<o:p></o:p>

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-----Original Message-----
From: Mel Bartels [mailto:<?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-comffice:smarttags" /><st1ersonName w:st="on">mbartels@bbastrodesigns.c om</st1ersonName>]
Sent: Sunday, 14 August 2005 12:31 PM
To: <st1ersonName w:st="on">david pretorius</st1ersonName>
Subject: Re: Hi from <st1:country-region w:st="on"><st1:place w:st="on">australia</st1:place></st1:country-region>

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Hi David<o:p></o:p>

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I don't know of anyone selling roller drives. People just build them. Have <o:p></o:p>

a machinest make a 1/2 inch diameter shaft a few inches long and then let <o:p></o:p>

that drive a wood circle rimmed with aluminum.<o:p></o:p>

<o:p></o:p>

Mel