BDGiven
Plastic
- Joined
- Aug 3, 2018
- Location
- Wadsworth, OHIO USA
Some time ago I picked up two of these mills to rebuild, as a learning experience...
One was running and the other had the steppers off and needed a Vari-drive belt.
After moving them to my shop I learned how to make a rotary phase converter, balance it all out, and watched where I hooked the generated leg. X axis popped a transistor after moving a few times. I replaced it and two more blew. That's when I decided to rip it all out and rebuild using the original steppers. This was supposed to be the cheap rebuild to flip for some capital to throw at the other machine.
So, I opted for 3 KL-11080 drives that have internal power supplies, a Chinese 5 axis breakout board, a 24VDC power supply for the limit switches, and Linuxcnc on an old PC I had laying around. Plus some new cables, then paint when I get it operational.
Here's where it started heading south!
I got all three axis moving with the stepconfig in Linuxcnc but the Limit/Home switches aren't working. I mean, they're all hooked up and correctly cutting voltage when activated but the signal change isn't making it to the PC. I found that I may need some pull-up resistors on the opto-isolators for the pins operating the inputs. Maybe? I disabled them till I get the rest sorted out. Because, I noticed "Z" axis wasn't traveling the correct distance.
My manual states the "Z" is a standard 200 steps per rotation at 2:1 to a 4mm pitch lead screw and I'm micro-stepping @ 10. (running in inches I had it set at 6.35 rev/in) The drive sounded good while moving fast and slow with the settings I had for that information, but the distance was off quite a bit.
I decided to put an indicator on the bottom of the quill and use the .100 wheel on the bottom of the motor the measure how far the quill travels for a full rotation of the stepper. The quill travels exactly .200" for one full rotation of the .100" graduated wheel on the stepper shaft! I took the guard off and counted teeth on the pulleys, both the motor and the quill have 26 teeth. 1:1 So I changed the stepconfig to 1:1 and played with the rev/in till it's traveling the correct distance. ( I know, NO GUESSING, But I'm not digging down to that ball screw to count threads!)
My Stepconfig for Z ended up;
200 steps
10 micro-stepping
1:1
5 rev/in.
.0333 s
.0167 in.
10000 Hz
10000 steps/in
It's traveling the correct distance and sounds good while moving fast, but it really doesn't like low feed rates. It's not right.
My other machine has the same pulleys on "Z" so I don't think someone swapped them both.
But the quill travels .200" down while the measuring wheel on the bottom of the "Z" stepper counts .100" for a full rev. That really bothers me.
Does anyone see what I'm missing?
One was running and the other had the steppers off and needed a Vari-drive belt.
After moving them to my shop I learned how to make a rotary phase converter, balance it all out, and watched where I hooked the generated leg. X axis popped a transistor after moving a few times. I replaced it and two more blew. That's when I decided to rip it all out and rebuild using the original steppers. This was supposed to be the cheap rebuild to flip for some capital to throw at the other machine.
So, I opted for 3 KL-11080 drives that have internal power supplies, a Chinese 5 axis breakout board, a 24VDC power supply for the limit switches, and Linuxcnc on an old PC I had laying around. Plus some new cables, then paint when I get it operational.
Here's where it started heading south!
I got all three axis moving with the stepconfig in Linuxcnc but the Limit/Home switches aren't working. I mean, they're all hooked up and correctly cutting voltage when activated but the signal change isn't making it to the PC. I found that I may need some pull-up resistors on the opto-isolators for the pins operating the inputs. Maybe? I disabled them till I get the rest sorted out. Because, I noticed "Z" axis wasn't traveling the correct distance.
My manual states the "Z" is a standard 200 steps per rotation at 2:1 to a 4mm pitch lead screw and I'm micro-stepping @ 10. (running in inches I had it set at 6.35 rev/in) The drive sounded good while moving fast and slow with the settings I had for that information, but the distance was off quite a bit.
I decided to put an indicator on the bottom of the quill and use the .100 wheel on the bottom of the motor the measure how far the quill travels for a full rotation of the stepper. The quill travels exactly .200" for one full rotation of the .100" graduated wheel on the stepper shaft! I took the guard off and counted teeth on the pulleys, both the motor and the quill have 26 teeth. 1:1 So I changed the stepconfig to 1:1 and played with the rev/in till it's traveling the correct distance. ( I know, NO GUESSING, But I'm not digging down to that ball screw to count threads!)
My Stepconfig for Z ended up;
200 steps
10 micro-stepping
1:1
5 rev/in.
.0333 s
.0167 in.
10000 Hz
10000 steps/in
It's traveling the correct distance and sounds good while moving fast, but it really doesn't like low feed rates. It's not right.
My other machine has the same pulleys on "Z" so I don't think someone swapped them both.
But the quill travels .200" down while the measuring wheel on the bottom of the "Z" stepper counts .100" for a full rev. That really bothers me.
Does anyone see what I'm missing?