Z too low

[nat_wheatley]

I was creating drilling toolpaths in PW's today and when I would try to run them, my air drill would start by lowering the bit below the surface of the material, then slowly raising up to the safe height as it moved over to drill the first hole. From there it drilled the holes correctly. What am I doing wrong?

[Gary Campbell]

Nat..
The first move in the file is: MZ, 1.000000+&my_ZinDrilloffset_T31 (assumes first drill) This is probably where you experienced the erroneous plunge, but if all is correct, you shouldnt have a problem with that line.
Did you run the "drill offset" file?
Was the spindle bit zeroed to the surface prior to running drill offset file?
What is your safe Z height in the file?
What is your "&my_ZinDrilloffset_T31" value (or correct tool number)?
What is the drilling (hole) depth

You should be able to solve this with math.
&my_ZinDrilloffset_T3x = Z height when drill touches material (positive number)

&my_ZinDrilloffset_T3x is always added to every height in every move whether it is positive (.5" for moves) or negative (-.5" for drilling)

To keep cycle time low, you want to have the safe z low, (around 1/2") and your drill adjusted so that the drill offset (Z) is near 1/2 of your stroke. That setting allows maximum cutting depth from both the drill & spindle.
Gary

[myxpykalix]

do you have your Z zero set to the top of the material or the top of the table?

[nat_wheatley]

Everything does add up, and it is drilling the holes correctly, at the correct depth. I'm working in mm and the drill offset file doesn't work correctly so I've been measuring and entering my drill offsets manually. I only adjust the ZmmDrilloffset and not the ZinDrilloffset variable and it may be that that's what's throwing off the first moves.
I'll take a closer look tommorrow now that I know what to look for.

[Gary Campbell]

Nat...
I figured it out...In metric mode the first move line should read: MZ,25.4+&my_ZinDrilloffset_T31, not 1 which is 1mm, correct?

You may need to edit the postP if it does this consistently.
Gary

[nat_wheatley]

It looks like my post file has a different line in place of that that reads "MZ, [ZH]+&my__T[T)'Move Z to safe height to acivate Drill"

I'm guessing ZH is the Z zero point which is the top of the material.

Both have 'ZinDrilloffset' which I'm guessing should be 'ZmmDrilloffset', and I also should have the 25.4 in there. I'll have to check what I've the T_32 value (using 2nd air drill) set at. But even with the existing code, if my ZinDrilloffset is set at any positive value, I'd think I'd be above the material, albeit only by the inch equivalant of the actual offset. I'll check today.