RF45 (MSC branded) with Ajax retrofit
I got a really good deal on this machine from work, we are getting a Hurco VMX42i for the shop. So we no longer needed this mill, I let my boss know I would like to buy the old machine for my self. Got a really good deal on it, and now its time to clean it up and fix all of the wiring in it.
From what I can tell it is a RF45, made in Taiwan, and the Ajax kit was purchased December of 2004.
The wiring is a complete mess. The guy who did the retrofit used extension cord cables for just about everything, including the limit switches. Every wire splice in the box is very sketchy, and I've had to fix a few of them in the past. The rest of the machine seems to have been well done.
Here are a few pictures
https://lh5.googleusercontent.com/-M...o/IMG_2470.jpg
https://lh5.googleusercontent.com/-9...o/IMG_2471.jpg
https://lh6.googleusercontent.com/-8...o/IMG_2473.jpg
And here is the wiring nightmare inside the control box....
https://lh3.googleusercontent.com/-q...o/IMG_2474.jpg
The 2 white wires running into this relay are a 2 wire home extension cord, that was for the coolant pump.
https://lh6.googleusercontent.com/-A...o/IMG_2475.jpg
I wonder if the wires under the tape were just twisted together?
https://lh5.googleusercontent.com/-Z...o/IMG_2476.jpg
And I guess he didn't like the length of the power strip?
https://lh6.googleusercontent.com/-D...o/IMG_2477.jpg
So the first thing I want to do is find a new enclosure and start over completely with the wiring. Thankfully I still have the original wiring diagrams, and the Ajax board is well labeled.
Re: RF45 (MSC branded) with Ajax retrofit
So I have been cutting a few small parts here and there, figuring out what tooling I want/need, and learning more about whats inside this machine.
I have 0.0028" backlash on the Y axis. I pulled the ball screw assembly out this weekend and cleaned everything up. Then I repacked the taper bearings and made sure they were set properly. The backlash seems to be coming from the ball nut. I am considering reballing the nut, I called one place that rebuilds them and was quoted $400-500. It has 38mm ball screws, fairly big screws.
I considered going with a smaller ball screw, but the ways are very tight. I was not able to move the table at all with the ball screw removed. And from what I can tell, the only adjustment on these ways would be to shim them? I have not been able to find any information on this style of linear bearing.
https://lh6.googleusercontent.com/-9...406771_HDR.jpg
https://lh4.googleusercontent.com/-p...416772_HDR.jpg
Re: RF45 (MSC branded) with Ajax retrofit
If you can't move the table with the ballscrew removed, THAT is your problem! ANY machine will have backlash with that much friction. With the screw detached, it should move almost effortlessly.
Regards,
Ray L.
Re: RF45 (MSC branded) with Ajax retrofit
Well you should be able to move it with a good hard push. If it is that tight you will get stick slip and that is never good.
Clean and adjust the ways. I can't see them but there must be a way to do it.
Pull the Y motor and turn the screw by hand. If you have no resistance when you turn the screw for almost any rotation then that is the screw nut or end bearing slop or ball mount.
You can pull the ball screw and re pack the balls for less than $50 but you need to know the exact size of the current balls. It is fairly easy to do the packing part but you really want to know that it is the nut first.
Bal-tecâ„¢, Manufacturer of Precision Balls, Ball Bars, and Kinematic Components has all the balls and can measure what you have. You will only need to go .0003" or so larger unless it is really loose which means it might be trashed.