Z Axis Plunging too Deep into part < part zero, tool offsets, turns ratio >

[martyscncgarage]

Please let me know if Im doing this right. tHOUGHT I was

I use a 123 block on the x table surface- touch my ref tool to the 123 block and hit F1 and set the z-ref. I then carry on with the other tools doing the same thing- touching off to the 123 block on the x table surface and then hit F2 to manual measure.

Still not sure why ots using the WCS- this does not make sense. The WCS is for the actual part that is being machined isin't it? I would think tool heights should be from a ref surface- let me know

Thanks

I thought you were using HOME as your Z reference?? You set parameter 3 to the value of 2, using Z home as your reference point.
If so, you DON'T use a reference tool.
Rewatch THIS video since you have a bedmill. Starting about 19:00



You never see Keith use a REFERENCE tool in this video.

[milling]

I was using home ref. I thought you said earlier to go back to z ref? So should I go back in and change parameter 3 to 2 and then redo my tools again? Sounds like I was doing that part right before then- correct?

[milling]

This is what you sent earlier and I thought you meant set it back where z ref has a number. You are correct when I watched the keith video his ref- said "home" and then he set his tools off the table and hit f2

Ill try it again and let you know what happens- thanks

[cncsnw]

Tool measurement and Z part setup will work just fine with a Reference Tool, and it will work just fine with Z Reference set at Z Home.

If you are setting part zero using a measured tool, and you have measured the tool before setting part zero, then it will work just fine.

Note that setting P3 = 2 does not cause Z Reference to be set to Z home. It just prevents you from changing Z Reference. You have to actually set Z Reference at Z home -- using F1 in the Offset Library while Z is at home -- before you change P3 to 2.

Z Reference is always stored internally as a machine coordinates location. When it is displayed as a number in the offset library, it is displayed relative to the current part zero, so that it matches up with the DRO display.


Marty: I think you are confusing lathe tool changes ("T0202") with mill tool changes ("M6 T2" / "G43 H2").

[martyscncgarage]

Tool measurement and Z part setup will work just fine with a Reference Tool, and it will work just fine with Z Reference set at Z Home.

If you are setting part zero using a measured tool, and you have measured the tool before setting part zero, then it will work just fine.

Note that setting P3 = 2 does not cause Z Reference to be set to Z home. It just prevents you from changing Z Reference. You have to actually set Z Reference at Z home -- using F1 in the Offset Library while Z is at home -- before you change P3 to 2.

Z Reference is always stored internally as a machine coordinates location. When it is displayed as a number in the offset library, it is displayed relative to the current part zero, so that it matches up with the DRO display.


Marty: I think you are confusing lathe tool changes ("T0202") with mill tool changes ("M6 T2" / "G43 H2").

Thanks for clarifying the P3 issue Marc!
Marty

[milling]

I noticed cncsnw said something about the z-home in the tool setup. Should I go about this a different way so that when I hit tool check or hen a program runs it goes right back to the home switch?

[milling]

I will try this- not sure i did it this way or not?

"Note that setting P3 = 2 does not cause Z Reference to be set to Z home. It just prevents you from changing Z Reference. You have to actually set Z Reference at Z home -- using F1 in the Offset Library while Z is at home -- before you change P3 to 2."

[milling]

Still a little confused on this- is this the sequence
1. set machine to home position
2. set machine parameter to 2

[cncsnw]

Regarding your "move to home" question:

Programs normally do an "M25" or "G91 G28 Z0" move at the start of the program, at every tool change, and at the end of the program.

Those moves take Z to the previously-found-and-set Z home position. They do not search for your switch again.

While there, if you temporarily switch your DRO display over to Machine coordinates (by pressing Alt-D), then when Z is at home, the position should read 0.0000.

If you switch back to local WCS coordinates (by pressing Alt-D again) then the DRO position will resume showing the distance between part zero and the current cutter tip (dependent on the active height offset, which is shown in the status window at the upper right).

If you are losing steps, then over time there will start to be a difference between the Z home that it found on power-up (and that it will move to again if you run "M92/Z"); and the position it goes to when you run M25 or press Tool Check, to move to machine zero.

[cncsnw]

If you want to always use the Z Home position as the Z Reference position:

0) Power up the machine and control, and let it home itself as usual.
1) Move the head to home by pressing Tool Check.
2) Go to the Tool Offset Library (F1/Setup -> F2/Tools -> F1/Offsets)
3) Press F1 to set Z Reference
4) Press F10 to set Z Reference at the current Z position (still at home)
5) Press ESC three times to return to the main screen.
6) Go to Machine Parameters (F1/Setup -> F3/Config -> "137" -> F3/Param)
7) Change Parameter 3 to a value of 2.0
8) Press F10/Save
9) Press ESC twice to return to the main screen.