The best information about timing belts will come from the belt manufacturer's web site or from a belt reseller like https://sdp-si.com/ SDP-SI has a lot of good theory-based articles on belts and belt tension and so on.
One thing to know is that the older belt designs used trapezoid teeth. The new ones use rounded sine wave shape teeth. The new belts make less noise and are stronger for a given size and can get by with less tension. If noise is an issue, you might change the belt, but that means also changing both pulleys On Sun, Jul 3, 2022 at 1:23 PM John Figie <zephyr9...@gmail.com> wrote: > I am back to making slow forward progress on the Clausing NC since > putting on hold back in March. The lathe came with the 5HP motor > already mounted and I have kept this as is from the previous owner > that gave up on the retrofit. The original lathe had a mechanical > variable speed drive with pulleys similar to that on a bridgeport > variable speed head. I have mounted and wired up a Huanyang 7.5 Kw VFD > for the motor and first ran the motor today. I am using a 7.5Kw > inverter to allow for derating for single phase per Huanyang > recommendations. > > I have about 1" of deflection in the belt. The belt seems quite noisy > when running the motor at 1725 RPM. I have not yet attempted to run > the motor at 3200 RPM which is my goal to get 2000 RPM spindle. > > Are these kinds of timing belts usually noisy? > The original clausing manual says have 1" of belt deflection - but > they don't specify a force. Also the original timing belt was probably > about 3/4 as long as the one I have now because of the way the > variable speed drive was mounted. There isn't much clearance between > the belt and the z axis motor like 1/4" but increasing that clearance > would make less clearance to the spindle drive encoder (not mounted at > the moment). > > https://photos.app.goo.gl/hSYW84zZsdnoKdr79 > > Motor running at approx 1725 RPM > https://photos.app.goo.gl/FxjZn6QRmztM1TQk8 > > John Figie > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
