Kx1 stepper motor.

[Sparkplug]

Hi. I've owned my Seig kx1 cnc milling machine for thirteen years with no real problems. I'm fine with mechanical problems but electronics is a completely different matter. Over the past few weeks I've been experiencing several problems when running proven programs, such as the program stalling during its cycle and the spindle not returning to home when the go to zero tab is clicked. I've also had the control seeming to loose its programmed position and sending the cutter of in a different direction. It was suggested that the problem might be the slide ways sticking, as my machine doesn't have one shot lubrication and I haven't stripped or cleaned the gibs in thirteen years it was a distinct possibility. I've cleaned the X axis slides and gib strip and given everything a good spray of ptfe slideway lubricant. After several hours of adjusting the gib screws I can jog for about three inches in either direction when the cross slide is centrally positioned but jams either side of the central position. I suspect this is due to thirteen years of wear in that area, however the slide moves freely when driven by a spanner rotating the ball screw. So it would appear that the stepper motor isn't man enough to jog the slide either side of the central position. My question is, would simply replacing the existing stepper motor solve the problem, or would it need replacing with a more powerful motor and if so is this difficult? Thanks

 

[RM-MN]

It depends what the real source of the problem is. Stepper motors come in various frame sizes and lengths with longer ones taking more amperage and developing more torque. Then it depends on how the stepper is connected to the ballscrew. If it is a simple coupling, then releasing that from the motor shaft, removing the four screws that hold the motor to the mill and putting on a different motor...provided that the different motor has the same diameter and length of shaft.

Compare these two stepper motors to see some of what I said:

https://www.ebay.com/itm/2640040576...h%2F58x5TA%3D%3D|clp:2334524|tkp:BFBM9MKl7NJf
https://www.ebay.com/itm/264803948809?epid=18039728186&hash=item3da78b9909:g:THQAAOSw9GJfF6Zf

 

[ddmckee54]

If the motor used to work correctly it still should work correctly, unless you've let the magic smoke out of something - then usually NOTHING works. I've been doing this crap for over 40 years, and usually the electrical stuff is not to blame, it's usually something mechanical that has worn out or broken. But I'm an electrical guy and I MIGHT be a little biased.

What's it do when it jam's? Have you tried loosening the gibs to see if you can get past the 3" of travel? Are the Y axis stepper and the X axis stepper the same size? If so you might try swapping them to see if the problem goes to the other axis. I'd only try swapping them if they have the same style connector though.

If you want to increase the torque on your motor, as long as you stay within the same Nema frame size the mounting hole pattern will remain the same. I believe that shaft size will also remain the same within the same Nema size. The length of the motor will change though, that's how you get the different torque specs. The higher the torque the motor has, the longer it is. The problem with just changing the motors though is that your stepper driver may not be rated for a larger motor.

Don

 

[Mago]

I have a Sieg KXi cnc machine of the same vintage .I'm not a fan of Chinese machines but must say that the KX1machine is exceptionally well made.
Having said that your machine is not mechanically at fault.
I would assume that your driving computer is thirteen years old and could be the source of trouble.
Likewise your program running it is the same age and could be in need of a complete re install in a clean computer
If this does not help then you must go looking more deeply.
Good luck with the search.

Mago

 

[Mike Ginn]

Hi Guys.
I have a little used KX1 running on a parallel port of a XP desktop. I use CAMBAM for G-Code and Autocad DXF for designs.
When I cut a circle its not round! I have changed parameters in Mack3 but it doesn't really solve the problem. I am reluctant to take out the lead screws to check back-lash as I don't have any mechanical diagrams.
Question:- has anyone experienced this problem?
Has anyone any mechanical drawings of the KX1. I did not receive anything with the mill which was purchased from Arc who no longer offer support.
Is there any support for the mill in the UK?
Many thanks
Mike

 

[Mago]

Mike, have you had a look at the gcode file that you are using and see if it is actually programmed to produce a perfect circle
If the problem is with the software you are using you could use as a trial, Delta cad for your dfx drawing, Sheetcam for gcode production.
I'm not sure you can get trial versions but it is another way to avoid all the mechanical work. Good luck
I found no support with Arc euro or Sieg in China, you are on your own.
Mago

 

[xpylonracer]

I had the same problem until the backlash was reduced in the X axis, now get acceptable results.

xpylonracer

 

[RM-MN]

Hi Guys.
I have a little used KX1 running on a parallel port of a XP desktop. I use CAMBAM for G-Code and Autocad DXF for designs.
When I cut a circle its not round! I have changed parameters in Mack3 but it doesn't really solve the problem. I am reluctant to take out the lead screws to check back-lash as I don't have any mechanical diagrams.
Question:- has anyone experienced this problem?
Has anyone any mechanical drawings of the KX1. I did not receive anything with the mill which was purchased from Arc who no longer offer support.
Is there any support for the mill in the UK?
Many thanks
Mike

Fasten a dial indicator to the table with the stem against the spindle, then use the jog function of Mach 3 to move the table in the x direction and note the distance as compared to what the jog should have been. Then jog it in the -x the same distance and see if the dial indicator returns to zero. Any deviation would indicate backlash unless you have programmed in backlash compensation, which is a function available in Mach 3. Repeat for the y direction. Once backlash is measured, you can use the backlash compensation to get the mill to make perfect circles.

 

[Mike Ginn]

Guys, thank you for your ideas/suggestions. I need to carry out some trials with different G-Code generators. I did apply compensation in Mach3 but it was guess work - never thought of dialing it - great suggestion.
A question for xpylonrace. How did you reduce the backlash. In a perfect world I would always try to tighten-up any mechanics before applying software fixes.
A question to the forum. Does anyone have a detailed mechanical layout of the KX1?
Thank for your help and support
Mike

 

[xpylonracer]

Mike

The machine was an Emco 5 cnc lathe on which you can adjust the tension on the ballscrew by turning a nut, reducing the backlash gave improved results.

xpylonracer