Introduction: Mach3 Zero Probe Tool

This is a Simple Guide on how to use a Probe Tool in Mach 3 to find the exact top of a material.
You can use an input on your CNC Controller, but if you don’t have free inputs because they are used for Limit Switches like in my case. You can just get another CNC Controller when you have an Additional LPT Port, and if not they are very cheap.

I have attached a LED on my Probe, but it has no function other than a visual indication. So the Resistor and LED it not needed.  Just a wire and a Metal block will work as well.

What I used is :
A very CNC Controller from eBay for 12$ (5 Axis CNC Breakout Board For Stepper Driver)
You just need a free Input Port on your Controller.

This VB Source code for the Probing Tool.
'VB Code Start
CurrentFeed = GetOemDRO(818)

ZMove = 20.00 'Total lenght of Probe to move before Stop or no Contact Made.
ZOffset = 1.60 ' Plate Hight
ZSal = ZOffset + 2.00 '+ Free Hight, Will possition the Proble 2 MM over the Material.

StopZmove = 0
If GetOemLed (825)=0 Then
DoOEMButton (1010)
Code "G4 P2.5"
Code "G31 Z-"& ZMove & "F25"
While IsMoving()
Probepos = GetVar(2002)
If Probepos = - ZMove Then
responce = MsgBox ("**ERROR** " , 4 , "Probe **ERROR**" )
Code "G0 Z10"
StopZmove = 1
Code "F" &CurrentFeed
End If
If StopZmove = 0 Then
Code "G0 Z" & Probepos
While IsMoving ()
Sleep (200)
Call SetDro (2, ZOffset)
Code "G4 P1"
Code "G0 Z" & ZSal
Code "(Z zeroed)"
Code "F" &CurrentFeed
End If
Code "(Check Ground Probe)"
End If
Exit Sub
'VB Code Stop