I just purchased a Colchester Triumph Roundhead Lathe this morning - 15 inch Swing over bed. Purchased it from a large machine shop that primarily does CNC work for customers. They used this lathe for some one off projects and misc. shop maintenance requirements. Very clean and well maintained machine with newer 3 jaw chuck. Was able to see it running through all the gears and cutting. Ran real quiet and smooth. All the slide are tight and minimal backlash on the leadscrews and half-nuts. Bed ways are hardened and in good condition. See pics attached of the lathe I purchased.
It is currently a 5 HP 1750 RPM motor - 3 phase 575 volt. I only have single phase 240 volt in my shop so planning to install a 5 HP 1750 RPM 3 phase 240 volt motor and power it with a VFD. I have been looking at the VFD's sold by Vevor - thinking I will get their model A2-8075 - 7.5kw 10HP 240 volt - single phase input - 3 phase output.
I have a few questions on doing this conversion as follows
It is currently a 5 HP 1750 RPM motor - 3 phase 575 volt. I only have single phase 240 volt in my shop so planning to install a 5 HP 1750 RPM 3 phase 240 volt motor and power it with a VFD. I have been looking at the VFD's sold by Vevor - thinking I will get their model A2-8075 - 7.5kw 10HP 240 volt - single phase input - 3 phase output.
I have a few questions on doing this conversion as follows
- The lathe is currently started using a lever with a red knob on the side of the head stock. See picture with arrow pointing to the lever. I assume that lever engages a switch inside the housing. The same lever is also use for braking. I have read that it is better to start and stop the motor using the buttons on the VFD itself. The Vevor VFD has a removeable control panel that I could mount remotely on the headstock and not use the lever on the lathe. Would it be better to do that or alternatively I could rewire the start switch on the lathe to provide an input to the VFD and tell it to start.
- Similar for reversing the motor - there is a small lever near the start / brake lever that is switched to reverse the motor direction. Should I use the VFD controls panel only for reversing or alternatively rewire the reversing switch on the lathe to provide a signal to the VFD ?
- This is my first VFD conversion - I have read that some people add an inline filter on the input side also some install a braking resistor. I wasn't planning to add a filter unless I ran into interference problems and since the lathe already has a hand brake wasn't planning to add a resistor
- If anyone has an electronic version of the manual for this model of Colchester lathe it would be great to get a copy, especially the wiring diagram and section that describe control lever functions and lubrication recommendations.
- If anyone has any other suggestion on converting, maintaining and operating this lathe your input will be appreciated.