I have chance of buying a 1980's Tong-il Korean Knee mill, with No 4 Auto lock chuck and rotary table for 650 Euros. I cannot find any other Mill of this size for the same money anywhere close to where I live, so I am considering it a probable good buy. The seller is a retired Engineer. The mill is in four pieces, so its hard to take photos but I have inc a picture of the same mill in this post.
The Idea is to convert it into a CNC Mill. I have been told the Z will have lots of backlash, and I should only convert the Quil to stepper motor / not the knee. But this limits performance doesn't it ?
I would like to know how much work is involved in this conversion...IE.....Am I capable of making the parts on my sturdy little CNC/router (mills billet aluminium without problems) ?. Or is this a worthless venture with this type of mill ??. I want to be able to mill aluminium and steel, as well as bore very accurate holes up to 80mm in Dia. I understand I will have to change Acme leadscrews for Ballscrews. How difficult is this (to fit the ballnut etc)
I have been told the motor is a 3 phase 3hp or 5hp motor. Can I use a chinese VFD like this one (for a 3hp motor) 4HP 3KW VFD DRIVE INVERTER SOLUTIONS CONTROL LOAD CAPABILIITY WIDELY BE USED | eBay
And can I use this for controlling motor speeds / torques ?



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