Hi all, this is Sami with Avid CNC, and this is a Pro-Tip video on how to use the
Auto Z and Corner Finding Touchplate with the Avid CNC Mach4 screen set.
This tool allows you to quickly and easily find precise settings of your workpiece
height, corner, and edge location.
It's dual-sided for Z only X Y Z finding.
It also has a spring-loaded brass plate safety feature,
quick connecting magnet, and corner finding wall.
In this video, we'll cover the basics of how to set up your work offset
using the Auto Z & Corner Finding Touchplate.
Go ahead and turn on your CNC controller,
once your controller is on and connected to your PC, open Mach4.
The first thing we'll do is home our machine.
Click Home XYZ.
This will send signals to move the machine in each direction
and trip the sensors at the end of each Axis.
This will establish the limit of machine travel,
reset the machine Zero, and ensure that both sides of the gantry are aligned.
Once we've homed, we want to give our machine what's called work offsets
from the machine coordinates
that move the G-code program origin or our zero
so we can locate our project in a more convenient location.
Let's establish a fundamental understanding of machine coordinates and work offsets.
When we click Home XYZ
this allows the machine to find its machine coordinates
or the limits of the machine.
Often, this is the front left corner.
This allows the machine to understand its work envelope represented in green.
I like to think of this as the machine waking up in the morning,
it's a little sleepy and needs to search around for its glasses on the bedside table
so we can figure out where it is in space.
Now we need to give the machine offsets, from those machine coordinates,
to tell the machine where the material is located in relation to the machine coordinates.
This is understood by the controller as X-Y-Z offsets.
We can think of this as the starting point from which to run our G-code.
One of the simplest ways to set your Zero or your workpiece coordinates
is to choose a corner or reference point on a workpiece.
We have a few options here which might be influenced by
your material type, shape, and tool path operation selections.
So, when we run our G-code the work offset also known as our Zero will be our starting point.
This is like the starting point on a map,
and the tool path is the route on the map for the machine to follow.
The G-code is like the instructions on how to follow that path,
written in a language the machine can understand.
The code includes how far, how fast, and in which direction to move
from that starting point.
Similar to following a route on a map.
We have to set our Zero twice. Once in our G-code exported by our CAM program,
and once when we're setting up our project on the machine and in the controller program.
If we give the machine the incorrect starting point on the machine
that doesn't match the selected corner in our CAM program,
this is similar to giving a friend a map but placing them at the wrong trailhead.
They just won't get to where they want to go.
So, ensure that you have selected the same corner in your CAM program
and as your setup on the machine.
We recommend you use the 10-step Cycle Start Checklist every time
you're ready to run a program.
We've linked a video to this in the description below.
In the VCarve initial file setup, we can select our Zeroing point.
For a Z-Axis we can select the material surface or the machine bed.
For our X-Y location, we can choose any of the four corners of our workpiece.
You can rotate the touch plate so the corner wall snugly fits on your selected corner.
I'll use the front left corner.
In Mach4 let's double-check that our touch plate is operating properly.
To confirm that the touch plate is able to form a complete circuit,
touch the magnet to the brass plate.
On the Mach4 screen,
the probe signal will light up as active. You can also place the
magnet on the router bit and then lift the touch plate to touch the router bit.
If the probe signal lights up as active, then you're ready to go.
Let's go ahead and set our Zero to the front left corner and surface of our material.
Confirm that this is the same corner you've selected in your CAM program.
Go ahead and open the Auto Z & Corner Finding Touchplate window.
Enter the diameter of the router bit you're going to use to set your work offset.
We have nine options corresponding to the touch plate zeroing operations.
When you hover your cursor over the button,
it will display a box explaining what that operation will do.
I'll place the touch plate on the corner of our material and then drive the spindle
over the touch plate, so the bit is about centered and one inch from the brass plate.
Then attach the magnet to the router bit.
Click the corresponding image on the zeroing window.
I'll select the bottom left corner.
The bit will lower until it contacts the brass plate.
This will complete the circuit, sending a signal to the machine,
allowing the program to calculate the distance the bit is from the material surface.
The bit will then lift up, and Mach4 will prompt us to rotate the bit.
So, the cutting edge of the flute touches the Y wall.
Then click ok.
The bit will move back to contact the Y wall.
Then Mach4 will prompt us to rotate the bit again 90 degrees to contact the right X wall.
Go ahead and click ok.
We have now set our Zero to the front left and top corner of the material.
Also, take note
when you load your g-code into Mach4. If you use the Avid CNC post processor version 1.3 or later,
the Z origin and XY origin will also be listed here in your G-code.
This is a great way to double-check your X Y Z Zero
after you've already exported your tool paths from your CAM program.
Let's talk a little bit about router bit selection in relation to the touch plate.
Starting with an End Mill, you can set your X, Y, and Z zero
though we should be conscious of the flute in relation to the walls of the touchplate.
Our goal is for the widest point, or the cutting edge of the flute, to contact the X and Y walls.
Alternatively, you can use a metal dell to find X and Y.
This will give us an accurate reading of the X and Y home.
Though you will have to re-zero the Z-axis when you switch out your bit.
Now there are a few bits we can only use with the Z-axis side of the touchplate.
Due to the angle and profile of a V-bit,
we can't get the reading of X and Y.
Though you can use the Z-axis side of the touch plate to set the Z offset.
Let's switch out our End Mill for a v-bit.
You can set your Z zero to the workpiece surface or the spoil board.
If there is a variation in the height of your material,
you can set your zero to the area you will be machining.
Place the touch plate on the surface you've selected.
You can also move the touch plate to the spindle rather than moving the spindle to the touch plate.
Attach the magnet, then click the center Z only icon to initiate the Z probe.
Now our Z zero is set to the workpiece surface.
We'll do the same operation to set the Z offset for every manual bit change.
If you have multiple tools in one setup, you'll only need to set your X and Y offset one time.
When you change out a bit, only zero the z offset.
For a walkthrough on how to perform manual tool changes,
check out the video linked below.
That's it for how to use the Auto Z & Corner Finding Touchplate in Mach4.
Thanks, y'all for watching. I can't wait to see what you make, and I'll see you in the shop.