Z-axis zero plate

[Romper]

I am trying to create a z axis zero plate. I am running mach 3 with a Bladerunner box. I wired an aluminum plate into the wiring for the z axis home switch and reversed the z axis home direction so that the router lowers to the plate. When the tool touches the plate it closes the circuit and stops. What I can't figure out is how to compensate for the thickness of the aluminum plate (.089") so that my zero is at the top of my work piece. I am a newbie to all this so a lot of help is needed. I would also be interested in wiring my zero plate into the Bladerunner box if someone knows how.

Thanks,
Morgan

[Jerry3672]

you can set the Z axis to .089 by clicking on the z axis DRO on the Mach 3 screen and type in .089, be sure to hit enter to complete. your z will now read .089.

[ger21]

http://www.cnczone.com/forums/cnc_wo...ro_setter.html

http://www.cnczone.com/forums/mach_w...x_version.html

[tulsaturbo]

Using a touch plate for the "Auto Tool Zero" function on the Mach3 program run screen. A nice way to set the z height.

1) Go to Config->Ports&Pins->Inputs, and configure a pin as the "Probe" input, making it Active Low.
2) Wire your touch plate to the Probe input.
3) Go to the Offsets screen, and, in the top-left corner, set the touch plate thickness to the exact thickness of your plate.
4) Go to Operator->EditButtonScript, then click on the AutoToolZero button. When the VB editor opens, delete the few lines of code in there, and paste in the following macro:

NOTE: You can replace the following with a known plate thickness such as .089"

PlateThickness = GetUserDRO(1151) 'Z-plate thickness DRO
with
PlateThickness = .089 'Z-plate thickness DRO

Macro:

PlateThickness = GetUserDRO(1151) 'Z-plate thickness DRO

If GetOemLed (825)=0 Then 'Check to see if the probe is already grounded or faulty
DoOEMButton (1010) 'zero the Z axis so the probe move will start from here
Code "G4 P5" ' this delay gives me time to get from computer to hold probe in place
Code "G31 Z-0.5 F5" 'probing move, can set the feed rate here as well as how far to move
While IsMoving() 'wait while it happens
Wend
ZProbePos = GetVar(2002) 'get the axact point the probe was hit
Code "G0 Z" &ZProbePos 'go back to that point, always a very small amount of overrun
While IsMoving ()
Wend
Call SetDro (2, PlateThickness) 'set the Z axis DRO to whatever is set as plate thickness
Code "G4 P0.25" 'Pause for Dro to update.
Code "G0 Z 0.5" 'put the Z retract height you want here
Code "(Z axis is now zeroed)" 'puts this message in the status bar
Else
Code "(Z-Plate is grounded, check connection and try again)" 'this goes in the status bar if aplicable
Exit Sub
End If

Click the following images to enlarge:

[Romper]

Tulsa turbo, When using your macro after zeroing on the plate the router is retracting to the top limit. I set the retract height to 1" but it still is going up past the top limit. Thanks for all the help

[CarveOne]

Originally Posted by Romper Tulsa turbo, When using your macro after zeroing on the plate the router is retracting to the top limit. I set the retract height to 1" but it still is going up past the top limit. Thanks for all the help

The numbers are in millimeters. If you have Mach3 set for inches, it will attempt to retract to +25.4 inches (oops! )

I just installed this VB code this past weekend.

CarveOne

[Romper]

Thanks everyone, It worked great.

[RandEE]

Thanks TulsaTurbo for such a detailed instructions. I have trying to figure this out. My question is that the controller for my mill doesn't have any available input switches. Can I just wire the touch plate directly to a parallel pinout? If so, how?
THANKS!

[foam27]

I wanted to thank you as well Tulsa, I've been torturing myself for years without this macro...lol