This only helped until I rebooted Mach3 then it went back to missing steps when direction is changed. I tried lowering acceleration and speed in motor tuning, but it just ran slower and still missed steps. I searched google for similar problems and read for hours. I tried different settings at random but nothing seemed to help.
I removed the Z axis motor from the lathe and reinstalled the wheel to see if the motor is still missing steps. I did this to eliminate the backlash nut, gibs, and any other form of binding. It was still missing steps.
Next I suspected XP and all of the programs and data I had on there. I had already disabled everything, but since I had a hard drive laying around why not start fresh.
I installed a 19GB hard drive into my tower, so I could format and reinstall XP and not loose my data.
I formatted the disk in ntfs, installed XP SP1 in standard PC mode. Before it was running SP2 so I thought SP1 might be better.
I followed the instructions on
http://www.machsupport.com/downloads/XP_Optimization.txt except for #9 because I installed in standard mode.
I ran driver test. Preparation was successful, PPS ran between 25038 and 25039, pulse rating is system excellent.
I downloaded and used the Sherline lathe (inch)xml found at
ftp://machsupport.com/XMLs/Sherline%20Lathe%28Inch%29.xmlIn bios
Peripheral config mode is set to ECP, ACPI Suspend State is S3(STR). I also set Peripheral config mod to EPP1.9, but it did not help.
I start Mach, selected Sherline lathe and select manual. It reads that the driver successfully initialized.
With the motor on the desk it still looses steps jog inc .01 feed 6 or feed 1 alternating direction.
It will not loose steps if I keep going in the same direction. It only happens with a direction change. After 10-12 direction changes it looses .001 on the dial of the wheel. My Z would get .012 out after peck drilling 1.5" when it was hooked up to the lathe
I moved the wire from the PC to the driver box and the driver box to the motor away from any other wires, which also did not help.
I can install the Linux software that came with my lathe and see if it is still losing steps. It is the only way I know to eliminate the software. I don't want to use Linux because I can write my own macros in mach using VB.
Any help would be greatly appreciated.
Lewis