This is my first post on the forum, so I thought I’d share our (mis)adventures with our current project(s).
We shut down our engineering business 3 years ago following my partners illness and we both now want to dabble with machine tools again, so are keen to CNC retrofit a milling machine for disabled use.
Earlier this year we purchased a new (to us) 1996 KRV2000 mill to replace our RF45 clone (Chester Superlux) we had from new in 2012. The RF45 clone was great, but after much consideration we chose not to go with converting the RF45 because it just didn’t have enough travel and was not rigid enough for what we wanted. We did consider a “small” bed mill like a SMX2500, but it would have needed to be disassembled to get it in the new workshop, and would have been too big anyway.
The plan is to do a CNC conversion on it with linuxcnc 7i76e/7i85 combination. The machine was tested and then stripped for cleaning and maintenance. Apart from new brake shoes and a single spindle bearing it was in pretty good shape.
We have called her Matilda and she was filthy. In a backlash to this we decided on a ‘force you to clean it’ white paint job!
The entry door on the column was modified to take an enclosure for the two vfds (one for spindle one for coolant motor). The coolant system has now been relocated externally after the incredibly unpleasant task of cleaning the sump – which we have vowed never to repeat – ever!
A new controller box has been made from an old van vault which has been resized and welded to bolt onto the side of the column to replace the original and give plenty of space for the controller, PC, servos and contactors etc. An overhead arm is currently being made to take the monitor, mouse and keyboard, along with an emergency stop and eventually a pushbutton power drawbar as an additional project.
Our lathe had a drip feed system that worked very well which has recently been upgraded to use the original single phase coolant pump and reservoir supplied when we bought the lathe new in 2014 (which drowned everything and then didn’t drain) with a SCR chopper circuit to control the flowrate. It now works pretty well for what we want, so we decided to use something similar for the mill.
The electronics are currently on the test bench. We went with Lichuan servos purchased on AliExpress from the manufacturers shop and have replaced the original Huangyang vfd that we used for the conversion to single phase with a Nflixin 9100 that outputs 380v 3 phase which is now being used on the test bench while the HY is used to get the mill up and running again manually so we can machine parts for the CNC conversion. We are running Debian 9 with linuxcnc 2.8.0-95, and have had quite a bit of success with the controller which is currently controlling spindle vfd, servo motors and limit switches etc successfully, and have got familiar with probe basic GUI and have been impressed so far.