Modern CNC machining calls for both accuracy and economy.  Measuring items when they are still in the machine—referred to as in-process gauging—has various benefits.  After machining, it replaces the requirement for hand measuring; it also lowers downtime and allows automatic tool wear and alignment corrections.  In highly precise sectors such aerospace, automotive, and medical manufacturing, these advantages are especially important.

Before the component is taken off the machine, machinists can check part dimensions in real-time by probing in-process, therefore ensuring that features satisfy tolerance criteria.  Direct integration of probing procedures into your G-code allows you to establish a flawless workflow improving accuracy and reducing mistakes.

The 5 Steps to CNC Probing

Let’s explore each step in detail to understand the process and how it integrates with Renishaw Inspection Plus or similar probing systems.

Step 1: Activating the Probe

The first step in probing is to turn on the probe. This is typically done using a G65 macro call with a specific subprogram code. For example:

G65 P9832

This instruction starts the probe so it may be measured.  The required directions in the subprogram code (P9832 in this example) will help to safely start the probe.

Step 2: Positioning the Probe Safely

To avoid damaging the probe, it’s essential to use protected positioning moves. These are typically executed using a G65 P9810 command. For instance:

G65 P9810 X10.0 Y20.0 Z5.0 F120.0

This instruction advances the probe to the designated XYZ coordinates using the designated feed rate (F).  Should the probe run across a roadblock during its approach, it will stop gently rather than damaging anything.

Step 3: Measuring a Feature

Measurement of a particular feature comes next once the probe is positioned.  Renishaw Inspection Plus software offers several probing cycles for measurements ranging from bores to faces to edges. For example, to measure a bore:

G65 P9814 D1.3

Here, the D value represents the approximate diameter of the bore being measured. The cycle captures the measurement and stores it in a macro variable, such as #188 for bore size.

Step 4: Retracting the Probe

After measuring the feature, the probe must be retracted safely using another protected move. This is achieved with a G65 P9810 command, similar to Step 2. By retracting the probe, you ensure it is clear of the workpiece and ready for subsequent operations.

Step 5: Turning Off the Probe

The final step is to deactivate the probe to conclude the measurement process. This is done with another G65 macro call:

G65 P9833

This command ensures that the probe is turned off, conserving its battery and completing the routine safely.

Probing Applications in CNC Milling

In-process probing is particularly valuable for CNC milling operations. By integrating probing routines, you can verify dimensions, adjust tool offsets, and even detect part misalignment automatically. This capability enhances accuracy and reduces waste, making it essential for precision machining.

If your operations require precise and reliable components, you can order high quality CNC milling parts from trusted suppliers. Combining precision parts with effective probing routines ensures consistent results for every project.

Streamlining Measurements with Software

Many CAM software providers now offer built-in probing routines, simplifying the process further. For example, Renishaw’s Productivity+ software enables seamless integration of probing cycles into your machining programs. Check with your CAM supplier to explore the available options for your setup.

Modern CNC machining is mostly dependent on in-process gauging since machinists may reach unmatched efficiency and accuracy by using the power of software and automated probing.