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Warning

MillMage is in active development and in a prerelease state. Many operations and functions are not feature complete. Please report any unexpected behavior by searching for and reporting the issue or question in the MillMage Beta User Forum. Please include screenshots and as much detail as possible.

Beta Users: Finding Help

Find help and download the latest release candidate of MillMage in the MillMage Beta User Forum.

Users new to MillMage should follow the Getting Started guide.

Warning

This documentation is in active development and in a prerelease state. These documents are not complete and may include missing pages, broken links, and placeholders. Content is being updated as feedback is reviewed. Your patience is appreciated.

Tool Length Probing

This guide covers using a Tool Length Probe with the Probing Wizard to determine and set the length of the installed tooling. Tool Length Probes will vary in type, location, and material, but typically work the same — A sensor or mechanical switch is triggered when the tip of the tooling reaches the Tool Length Probe activation point.

hero image

Using a probe to do this isn't strictly necessary for basic CNC work – you can find and reset your Z axis zero manually after changing tooling — but it will reduce operation cycle time by removing the need to re-zero the Z axis after changing bits.

This is especially helpful when the Project Z Axis Zero Point is set to Top and has been machined away during previous operations, and can aid in project recovery and completion when the spindle, router, or tooling has slipped and been re-secured but potentially in a different position.

To follow this guide, you'll need:

  • A CNC machine with a built-in Tool Length microswitch or sensor
  • Tooling & bits
  • Wrench(s) to loosen and tighten the router or spindle collet holding the tooling.

How Tool Length Probing Works

Once triggered in MillMage, the Probe Wizard will:

  1. Move the tooling to the user-defined probe location along the X and Y axis
  2. Home the Z axis
  3. Move the tooling down the user-defined Search Z distance at the Fast probe feed speed on the Z axis until the probing switch or sensor is triggered
  4. Move the tooling up away from the sensor
  5. Approach the sensor again, this time at the slower Precise probe feed speed until the probing switch or sensor is triggered
  6. Set the new tooling Z axis zero point

Setting Up a Tool Length Probe

Window for selecting probes to edit

Define the parameters needed for successful tool length probing by selecting CNC Tools → Probe Settings → Tool Length Probe to open the Tool Length Probe configuration panel.

Access these settings within the Probing Wizard by selecting Manage Probe Configuration on the first page of the wizard.

If you've already set up Tool Length Probe, skip ahead to Probing.

Settings

Position X and Position Y

  • Position X is the machine coordinates (G53) of the Tool Length Probe on the X axis.
  • Position Y is the machine coordinates (G53) of the Tool Length Probe on the Y axis.

diagram/image showing probe location

Finding Position X and Position Y

Use MillMage to determine the Tool Length Probe location.

  1. Close the Probing Wizard if open
  2. Select the Move Window
  3. Use the jogging buttons to move and roughly center the tooling above the Tool Length Probe location
  4. Note the machine X and Y axis coordinates in the Move window, labeled Tool Position (M)
  5. Open the Tool Length Probe settings and update the Position X and Position Y values

Search Z

Search Z is the distance the tooling will move down seeking the Tool Length Probe.

Diagram showing search distance

Fast Probe Feed and Precise Probe Feed

  • Fast Probe Feed is the initial speed at which the tool will move down towards the Tool Length Probe. This can be fairly fast depending on your risk tolerance.
  • Precise Probe Feed is the typically lower speed at which the tool will search for the probe block after initial contact. This movement will be a very short distance and should be kept to a fairly low speed for accuracy.

Activating Tool Length Probing

Warning

Make sure that before you start probing for tool length that the spindle or router collet is tight and the tooling secure. The spindle or router must be off and not rotating.

Probing

Open the Probing Wizard by selecting CNC Tools → Probing Wizard, or by clicking the Probing button in the Move window.

Select Tool Length Probe.

Probing Wizard screenshot

Start Tool Length Probing

Select Execute Tool Length Probe

Screenshot of Probing Block page 1

Once executed in MillMage, the Probe Wizard will automatically and without further user input:

  1. Move the tooling to the user-defined tool length probe location along the X and Y axis
  2. Home the Z axis
  3. Move the tooling down the user-defined Search Z distance at the Fast probe feed speed on the Z axis until the probe is triggered by the tooling
  4. Move the tooling up away from the probe
  5. Approach the probe again, this time at the slower Precise probe feed speed until the probe is triggered
  6. Set the new tooling Z axis zero point

That's it! Run the remaining tooling-specific operations in the project or until the next tool change is needed. Run the Tool Length Probe in the Probing Wizard again after additional tool changes within the current project.

XYZ Probe Block

Place a machined block over the material stock or in a known position within the work area and set the Z-axis zero point.

Tool Length Probe

Establish tool length offsets when changing tooling in multi-operation jobs without changing the work Z axis zero point.

For more help using MillMage, please visit our forum to talk with MillMage staff and users, or email support.