i have 4 viper 95 drives. 2 for the y axis, that are slaved. 1 for x, 1 for z.
I'm using mach3, with a simple BOB to drive the drives
i'm running a program that does a large pocket (20" x 10" x .6"). I'm stepping down by .09" in z each time. I'm stepping over in x, y by .375"
At each Z increment point, you can see that the X axis is getting off by approx .008" in the positive direction.
The Y axis however is dead on.
What are some possibilities? All drives have the same parameters, rapid speeds and acceleration.
For the moment, i'm resetting my x position from the limit switch on each step. Thats fine for now, but i'd like to find a better solution
I'm using single ended US digital encoders, but I would suspect more error if it was due to noise.
You are loosing steps in the Encoder or Step input. Most likely the encoder
Zero the drive (turn off power then on) and Zero mach. Make a mark on the motor shaft.
Run your program, then tell the machine to go back to zero.
Read the drive's M command and it will show Encode and Step input counters.
( The M and S are going to be close since the drive is trying to make the zero)
If the S setting isn't zero then you are loosing step input pulses between the BOB and drive.
If the S is zero and the motor shaft is off, then you are loosing encoder counts.
Is it a single ended or differential encoder ? Are you using twisted pair cable
Manufacturer of CNC routers and Viper Servo Drives
www.LarkenCNC.com and www.Viperservo.com