I'm suddenly having problems with mach 3 acting weird immediately after a tool change.

Program conditions are:
Tool change is set to Mach 3 default (stop and wait for cycle start)
The tool height offset  is -2.916
G28 home position is x.1 y.1 z-.1 (machine coordinates)
Post processor is SheetCAM

Here is the part of the code I'm having issues with

N0000 (Filename: Side A step 2.nc)
N0010 (Post processor: Mach2.scpost)
N0020 (Date: 3/15/2010)
N0030 G20 (Units: Inches)
N0040 G40 G90
N0050 F1
N0060 (Part: Sportser  91-03 Rev. view layout for cam)
N0070 (Process: Drill, thru holes, T26: #3 center drill, 0.25 in Deep)
N0080 G28
N0090 (#3 center drill)
N0100 T26 M06  G43 H26
N0110 G0 z.375
N0120 M1 (check dro's and z offset)
N0130 G00
N0140 M08 (Flood coolant on)
N0150 M03 S3000
N0160 X-0.1180 Y0.5899
N0170 Z0.0197

Here's what happens:

1. Press cycle start and Mach 3 rapids to the home coordinates.
2. Program  stops and wait for cycle start after manual Tool change.
3. Press cycle start and the z axis RAPIDS down to z=0 in WORK COORDINATES?
4. Then feeds at 1 ipm down to z=-2.916 (height offset) IN MACHINE COORDINATES?
5. The the z axis rapids back up to Z=.375 IN WORK COORDINATES
6. Then the rest of the program runs flawlessly.

Here is what should happen:

1. Press cycle start and the machine rapids to home position.
2. It stops and waits for cycle start after manual tool change.
3. Press cycle start and the tool rapids down to z=.375 (work coordinates) and the continues with the rest of the program

I had this problem 3 or 4 years ago and can't  remember how I fixed it. I've spent the last two days  trying to figure this out, If anyone could help me, it would be greatly appreciated.

Thanks,

George
 

I am not sure if the M6 macros take effect with the Stop and Wait type of toolchange but try editing the M6 end macro to remove the safe Z contents of it.
Hood

There are 2 macros involved with M6 M6start and M6end. But as Hood said Check your SafeZ values first sounds like a combo of safeZ setting and cycling the tool offset because it does end up where it is suppose to yes?

Thanks, it was the safe Z.