DRO positioning is Wrong.How to fix?

[GisMo]

I have a small little 3 axis mill and I am running Mach 2. I am running Xylotex stepper motors 200 steps per rev. I.E. If I move the table from 0 to 1" the DRO reads 8.123. I have read the manual and have had no luck . Any Ideas are appreciated. thanks

[NC Cams]

DRO's are nothing more than counters. They add or subtrack count "ticks" as you move the sensor one way or another.

To get good resolution, they typically have many tiny "ticks" that are read and then divided electronically to convert to in or mm of motion.

There has to be a "decoder ring" someplace to tell the counter what the division ratio is for the tick count coming in to make it read correctly on the screen.

I'd be someplace somewhere something isn't programmed or the gearing isn't matched correctly....

[ger21]

Do you mean Mach's DRO's on the screen? If Mach's DRO's are off, your streps/unit must be set wrong. How are you moving 1 inch?

[GisMo]

Mach's DRO on the screen is messed up. I am moving 1" in MDI screen. but it thinks 1" is something more like .1" appx. Where exactly do I set that. These xylotex have 200 ticks and the setup reccomneds the microstepping 10 per step so 2000 is what I have programmed in. I also, have the motors directly spinning the screws. Thanks

[ger21]

In the motor tuning, enter 2000 times the number of turns per inch of the screws. (I'm guessing it's 10)

[Redline]

Xylotex is set up in 1/8th step mode by default .If you are useing 16 TPI screw and 200 steps per revolution that is 3200 steps per inch.If it is set to 1/8th step then you will need to multiply that number by eight. 8 x 3200 = 25600 steps per inch.Try that see what happens.