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Colchester Chipmaster %x20

We have a 5X20 Chipmaster at the museum where I volunteer. It has been a lovely little machine,and is very solid and ridgid for its size. We are having a problem with it at the present though, and would appreciate any information about the variable speed drive. It is one of those double cone arrangements with hardened steel balls between them. Tilting the axis if the balls makes the effective radius of the drive and driven cones change, thus varying the output speed. Our problem is that it will no longer change speed smoothly from hight to low speed or vise versa. Has anyone else had this experience? I suspect that the 5 balls are worn slightly, and I'm considering swapping them upside down to get the load onto a previously unused section of the ball. Is this reasonable, or should we just replace it with a shaft and a variable frequency drive?

Reply to
Grumpy
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I have one of these, which had the same problem. It sounded like acoffe grinder for a few years of occasional use, then I was told there are no parts available for them when shortly after I got mine it croaked in 1992 and I apparently got the last "spider" for it in the worked, for silly money. They said the insides were worn and it sounded noisy When it died again a year ago - 10-15 years later - I got a VFD with a remote control panel and never looked back. i should have done it ages ago. You don't get quite the wide speed range, although a 2 step puly woudl be all ti needs in conjunction with the high - lo wratio gearbox. Some info is on

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and there is a site with serial numbers if you want to put a date on it. Geoff

Reply to
Geoff M

Thanks for the information Geoff.

I suspect that that is the way to go. I think I'll just remove the two cones and shafts and replace them with a through shaft that fits the bearings. A variable speed with an external pot connected to the original speed change dial will pretty well fix things at minimal expense and maximum utility.

Thank you for confirming my thoughts.

Reply to
Grumpy

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