I picked up a dirty but low usage Enco 1236 belt drive lathe last summer and have just finished going through it and making it about as good as one of these little critters gets. It all started with irritation at the patterned spiral chatter finish produced during cuts. At first I chalked this up to cyclical feeding from poorly cut gears but this really was not the issue. I was noticing that my tenth reading dial indicator would "flutter" about .001" with the motor running and nothing rotating. I rebuilt the motor (new bearings) and changed out the belts and the problem still persisted. What was happening is that the motor, because of the way it is mounted behind the lathe, sets up a harmonic vibration that is imparted to the turned finish when the lathe runs. What I did to nearly eliminate this was pretty crude--I made a wooden wedge and tapped it between the motor & the back casting of the lathe base. To completely eliminate the issue I may install a 3 phase motor or DC motor and use rubber isolation mounts, but it works so well now I most likely will leave it. The motor mounts for these lathes are a hinged steel plate adjusted by a length of allthread. Apparently the mechanical resonance of this mess is such that the whole lathe buzzes during operation. With the wedge this resonance is at a different frequency and the lathe is smooth. There is a HUGE difference. Some other items to look out for: chips embedded in the drive gears. One chip between 2 gear teeth will create a cyclical feed pattern.
I will post some pictures of what I did to this lathe if anyone is interested. It isn't a Hardinge, but it works pretty well now. I have the head adjusted so that it cuts straight and the new Polish chuck I put on it has very little runout. I also adapted one of the hex 5C collet holders I use on my Bridgeport for use on the lathe. It works well and I will make a post on my Quick & dirty collet chuck conversion if anyone has interest.
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I will post some pictures of what I did to this lathe if anyone is interested. It isn't a Hardinge, but it works pretty well now. I have the head adjusted so that it cuts straight and the new Polish chuck I put on it has very little runout. I also adapted one of the hex 5C collet holders I use on my Bridgeport for use on the lathe. It works well and I will make a post on my Quick & dirty collet chuck conversion if anyone has interest.
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