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Dear Neil, like David Salter (MEW 238 page 10) I replaced my lathe's headstock drive belt with good quality orange link belting to cure a problem with vibration. Although my lathe looks like his Myford Super 7, it is a Far Eastern copy, badged as Warco. I bought it years ago after its original owner had traded it in due to the vibration. I discovered that the width of the cheap drive belt varied along its length such that the belt rose and fell in the pulleys' grooves, tightening and slackening the belt, thereby causing the problem. New belt - no vibration I Dear Neil, articles have appeared from time to time concerning cutting metric threads on an imperial lathe using different combinations of change wheels to produce an approximation of various metric pitches as an alternative to purchasing an expensive 100/127 combination gear. I have never seen mention in MEW of using the 63/80 combination which I came across on a South Bend forum. This can be used in exactly the same way as the 100/127 wheel to produce any metric thread with an error of approximately 1 part in 10,000, so although you would probably not use it to produce a new leadscrew for any of the usual shorter screw cutting jobs the error is completely insignificant. Even over a meter the error would be little more than a tenth of a millimetre.