The little guides WILL carry more weight then the large bush type will. Say the small guide is 1/2" (12mm), that would make the round shaft about 2". You're not going to use 2" shaft, is what I'm saying. For a hobby machine, either type 3/4" or bigger will usually suffice. I have some 15mm guides. I wouldn't use anything smaller. Most people go for 25mm or so. The 25mm ones come in longer lengths, and I suspect that most people just can't believe the 15mm ones can carry the loads they are rated at. Our machine at work has a cantileverd 1000 lb head riding on 25mm guides. It hangs about 4 ft beyond the rails!
They both should be used in pairs for any type of machine tool application.
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Gerry
Mach3 2010 Screenset
http://home.comcast.net/~cncwoodworker/2010.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management) |