Reply with QuoteMaybe this will help? It's written around the 950 , but the overall theory is the same. You can reach out to me for further help if you need...
Adjusting Servo Gains
Another Interpolation problem on A2100 with BSD4
I found someone else's post about Interpolation problem on A2100 with BSD4 ( https://www.cnczone.com/forums/cinci...2100-bsd4.html ) and we were having some of the same problems. I was wondering if someone could further assist on the issue. We have an Aroow 500 that cannot produce a good circle. When we started out the RPM/Volts 222.2 so, we followed the instructions in the previous post. It's ability to produce a decent circle did improve but, leaves room for improvement. One thing we were not able to do in the instructions was to get the Kv active gain to 2.0 "at any speed'. I can get it to be real close at any given speed but then if checked at a different speed it is way off. Also, what is the deal with the scales icon button to automatically balance. When I attempt to use that function, The Kv active gain is quite different when going from positive to negative direction on the axis. I was able to get it to be more consistent by entering the numbers manually. One last thing, my Kv adjust is in percentage (% Kv Adjust), should that be at 100%? Thank You in advance if you are willing to share your knowledge with me.
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Re: Another Interpolation problem on A2100 with BSD4
Maybe this will help? It's written around the 950 , but the overall theory is the same. You can reach out to me for further help if you need...
Adjusting Servo Gains
Re: Another Interpolation problem on A2100 with BSD4
Thank You. I'll take a closer look once someone else is in the shop.
Originally Posted by hmtr
Re: Another Interpolation problem on A2100 with BSD4
You also have adjustments on the axis drives. You need a axis and spindle drive tuneup. How close do you need to get on the circle and what diameter. Have you had the machine laser calibrated?
MIKE CNC Machine Services INC | Cincinnati Milacron MachinesCNC Machine Services
Re: Another Interpolation problem on A2100 with BSD4
It'd be nice to have the error under 0.001 in a 1" circle. No, we have never had it laser calibrated. It was at some point but, it's had various drives put in it from various sources. We also have a saber 1500 that had a ball screw put in it and we had a guy lined up to come out and laser calibrate it but he always put us off so we've just been running it. After reading up on this and looking at all the various settings, I wonder if these mismatched command scale setups are the reason we never could truly rigid tap with these two machines. They appear to jerk up rapidly at the bottom of a tap cycle and the amount they jerk up coincides directly to the feed rate you are tapping at...
Re: Another Interpolation problem on A2100 with BSD4
The Arrow -Lancer-Saber-FTV products ALL had Ballbars run in X-Y-Z at the UK-factory and had to be less than .020mm (.0078") circularity [Motor Feedback] and .015mm (.0006") circularity [scale Feedback] . Typically they were within .009mm to .012mm (.00035" to .0005") circularity and half that with scale feedback.
If you want to see where your problems are have someone run a QC20W Ballbar on your machine. 35 minutes max for X-Y, Y-Z, X-Z with a report Circularity, Squareness, Backlash, Servo-Mis-Match
and over 20 some diagnostics. Anyone with a good .0001" or .002mm TEST-Indicator and a 9/16" ball bearing can look at the end-play on the ballscrew.
They can disconnect the X, or Y-Axis Ballnut to see if it has lost its preload. They can easily tune the Servo Gain and Balance; even for Rigid Tapping.
Many factors multiply together to create a good circle. Good Foundations with a Precision Level; Low Mechanical Slop; Good Squareness and Servo Tuning and Spindle Bearing Preloads are some of the biggest factors.
