AutoZero Touch Plate

The AltMill is compatible with the AutoZero Touch Plate!

Before we begin setup, please download the latest version of gSender.

Set Up

Step 1: Unboxing

Each order for the AutoZero Touch Plate comes with:

• The AutoZero Touch Plate itself and
• A cable that has a green connector on one end, as well as a magnet and banana plug on the other

If your cable didn’t come with a green connector, you should find a spare one came with your board in a baggy or plugged into the board already (look for the writing “PRB” or “Probe”). These connectors are called 3.81mm pluggable screw terminals and can have wires attached to them using a regular, small flat head screwdriver. When you do this the wire order doesn’t matter.

Step 2: Update your gSender settings

All probing macros for the AutoZero are built into gSender, making it easy to set up.

On gSender, go to settings (gear icon at the top, right of the window) ➜ go to the ‘Probe’ settings ➜ and change the touch plate type to “AutoZero Touch plate” in the dropdown menu. If you don’t do this, or at a later time you find the probing macros are moving strangely, then you should come back to check that this setting is still correct.

We recommend leaving the “Probe Connectivity Test” option activated as well. If you’re not using gSender and have the AutoZero, we also provide macros for other common senders.

Your ‘Probe’ tab at the bottom right side of the screen should now update to show images of the AutoZero. These tell you how you should position your bit if you’d like to perform probing for that axis.

Step 3: Setting up the touch plate on your workpiece

The AutoZero can find the X, Y, and Z coordinates on rectangular pieces of material. The material should be square and flat to get the best reading. The AutoZero can also find the Z-height of most flat materials, regardless of their shape.

1. Start off by plugging the green pluggable terminal into the controller. Make sure that it is in the PROBE/GND terminal.
   
2. Plug the banana plug into the touch plate. There are two holes on the plate, either of which can be used to your preference.
3. For any probing with X or Y, you’ll need to set the block at the bottom left corner of your material. The inside edge of the bottom of the touch plate should be touching against the sides of the material.
   
4. If you are probing just the Z-axis, you can still place the probe on the corner normally, or flip it over and place it on the surface of the material. Probing will happen on this back lip.
   

Step 4: Probing

The AutoZero can probe in all three axes. The type of probing can be selected with one of the five options on gSender, which specifies which axis the machine will be probing for and which coordinates it will reset once the probing cycle is complete.

Before you begin, make sure that both the touch plate is connected and the magnet is connected to the end mill or a nearby conductive surface such as the shank of the router or the router nut. gSender will ask to check for the continuity of the plate before starting the process to ensure your probe has the proper connection.

For the “Z” Axis probe, the machine will move down and touch off the block to find the offset distance based on the touch plate’s thickness. Jog the end mill above the back lip of the touch plate, which is designed for doing Z probes.

For all other probing (XYZ etc…), jog the machine over the inner square before starting the process. Your end mill should be above the square so that when the machine starts to move down, the first surface your bit touches is that square.

You may see the options “Auto” or “Tip.” Auto measures the diameter on straight end mills and bits. Tip uses the tip of v-bits, tapered bits, and ball nose bits touching against the bottom chamfer to determine its position. Using the correct setting will ensure the most accurate probing for your bit.

Finally, click on the probe to check the continuity and start the probing process.

During the probing process, keep a hand against the plate to prevent it from sliding around. Be careful and make sure your hand isn’t in the way of the end mill.

Step 5: Remove magnet

Once your probing is complete, remove the magnet and move the touch plate out of the way. Your machine coordinates should now be updated and ready to use.

We hope you have an excellent experience with the AutoZero touch plate!

If you are running into any issues, make sure to check this video out below, as well as see our Troubleshooting section further down on this page.

Troubleshooting

Is the bit supposed to dent/bite into the plate when probing?

Most times no, but if the bit if very sharp it can sometimes leave a mark. This can be much more noticeable on the AutoZero because many touch plates have a matte finish but the AutoZero is quite polished.

Probing operation failed?

Here are some items to check:

1. If you are using unique bits (e.g. dado, some V-bits) and the widest point of the bit does not touch off on the side of the touch plate, it may not be suitable for the AutoZero. Nearly all cutting tools have been tested to work with the touchplate, but it’s still possible to find exceptions, such as:
   • Large, irregularly shaped surfacing bits that can’t fit inside the AutoZero for XY probing
     • However, Z probing with the plate flipped over should still work
   • End mills that are flat bottomed and short, or taper from a large shaft to a smaller cutting diameter (for instance 1/8″ shaft to 1/16″ cutting diameter)
     • These can still work as long as the overall bit sticks out far enough (over 20mm) from the collet – it will look weird when it probes because probing in X and Y might touch the shaft instead of the cutting flutes, but as long as you’re using Auto or you’ve specified the shaft diameter manually then the probing should still complete fine
2. If your tool is non-conductive, it would not work with the AutoZero
3. Make sure your work coordinates match your touch plate settings (usually G54)
4. Check the controller: first make a jumper connector by placing a wire into both ends of a spare connector. Insert the jumper connector into the controller. Open gSender, begin the probing operation. You should get the green go ahead to begin. If there is no change, the port on the controller might be the issue.

Using other Senders

Due to popular demand, we’ve created and tested macros to use the AutoZero touch plate with a variety of CNC control software beyond gSender.

If the software you use is not explicitly listed here, you can also follow instructions in the section titled “Macros for other senders” to use the AutoZero touch plate in a semi-automatic fashion as we work on expanding support.

Macros for CNCjs: Download for CNCjs

Macros for LinuxCNC/Buildbotics: Download for LinuxCNC/Buildbotics

Note: These macros were tested on the Buildbotics controller but they should also work with machines running LinuxCNC since they share identical variable / arithmetic formats.

Macros for Universal G-code Sender: Download for UGS

Note: The macros environment in UGS does not support arithmetic operations so probing with the X and/or Y axis using the AutoZero touch plate is a semi-automatic process. More specifically, you will need to click on the “Control Status (DRO)” panel and enter “/2” to halve the active coordinates in the X and/or Y after probing in these directions. If you have only probed either the X or the Y axis, you will only need to divide the coordinate of the axis which was probed.

Example dividing the X and Y axis coordinates after probing in UGS

Macros for other Senders: Download for other Senders

These macros will allow you to probe with the AutoZero touch plate using any CNC control software. Having said that, probing in the X and/or Y direction is a semi-automatic process in which you will need to manually halve the measure coordinate after probing.

To do so:

1. Run the desired probing macro.
2. If the macro involves probing in the X and/or Y axis (i.e. not probing Z alone), manually divide the coordinates you see after probing by 2.
3. Enter the command G10 L20 P0 X[divided X coordinate] Y[divided Y coordinate]  into the console substituting the coordinates in square brackets with ones manually calculated in step 2. If you have only probed either the X or the Y axis, you will only need to divide and substitute the coordinate for the axis which was probed.
4. Home X and/or Y to check if the tool is at origin

 Example dividing the X and Y axis coordinates after probing in any CNC control software