6 Factors To Consider When Selecting A CNC Control For Mouldmaking

Introduction

With the advent of CNC machining, many industrial processes have become automated and accurate. A large factor in ensuring this accuracy lies with the CNC controls, which ensure proper tool movement and accuracy during different processes such as cutting, milling, grinding and more. A specific industry, namely the mouldmaking industry, also benefits from this machine control system. However, it also has its own set of challenges. Therefore, the key question here is how to ensure that a CNC control is right for mouldmaking. 

How To Select CNC Controls For Mouldmaking?

First and foremost, it has to be optimized for the milling process, which is the primary way to create moulds. Next, the control should be designed to automatically smooth the movement of the axis. Lastly, one has to also consider that the milling machine should have precise control over acceleration and deceleration, both key for precise mould making. With these pre-requisites in mind, Walker Machinery, a major distributor of digital encoders, CNC controls and DRO units, shares 6 factors to consider when choosing a CNC control for this application.

1. Spatial Plane Function

The core or base of the mould is often the trickiest to create and program. It should be made accurately with the aid of machining on five sides, but without many discrepancies. For this, the coordinated movements of the machine would have to be minimal. A CNC control with a spatial plane feature can accommodate this successfully. With this function, the machinist can program each side of the mould base along the X, Y and Z axes without requiring a major change in the CAM program. Therefore, the tolerances on each side of the base can be much closer and much more uniform with one another.

2. Contour Deviation Monitoring

Another feature to watch out for is whether the CNC control has contour deviation monitoring. What does this mean? A CNC control should be able to follow the contours of the workpiece across the X, Y and Z axes with predefined tolerances. This means that the machine should have a set minimal amount of contour deviation as the tool moves across the workpiece. How is this possible? For this to occur automatically, the CNC control must have an internal function that monitors the contour deviations closely. 

3. Compatibility With A Linear Encoder

When the cutting tool moves across the X axis, the CNC control must be able to precisely replicate that motion. For instance, if the cutting tool is moving from X-plus to X-minus, then reversing from X-minus to X-plus, then it should follow the exact same path as closely as possible. To ensure this, one has to install a linear encoder, which provides an accurate value of the movement and can help the machinist identify any minor deviations. Therefore, a CNC control must be compatible with digital encoders, such as a linear encoder, to ensure accurate movement of the tool on a set path.

4. Vibration Mitigation

Another problem plaguing CNC machining, especially in the field of mouldmaking, is vibrations. The main culprit of vibration in this setup is the very fast movement of the cutting tool across an axis, or a change in direction. Another probable cause if the cutting tool is having a higher-than-permitted feed rate. This results in excessive vibration, which can compromise the quality of the final product. Thus, a CNC control must be able to closely monitor any vibrations caused by either high feed rate or rapid/dynamic movements and control the speeds accordingly so that the final product is not negatively impacted.

5. Operator Flexibility

A CNC control that accounts for operator flexibility is a major bonus. How can this be accommodated? The main way is to allow a feature that optimizes the dynamics of the machine as required. That is, the program should be easily modifiable for better optimization. A classic example is manufacturing several different moulds on the same machine with different surface finishes, accuracy levels and lead time requirements. All this can only be accomplished by a CNC interface that offers the operator the flexibility to modify its programming.

6. Automatic Feed And Speed Adjustments

Lastly, CNC machines face the challenge of going through workpieces with different thicknesses. This means that the tool speed and feed rate have to be adjusted accordingly. To avoid this, CNC controls, which can automate this process, are highly valuable. This can be done by placing sensors connected to the main CNC machine that can measure various parameters, such as spindle speed and vibration. As the thickness of the material changes, these parameters change too, indicating an adjustment. With this technology, the feed rate and tool speed can be adjusted in milliseconds.

Conclusion

To sum it up, CNC controls play a major role in ensuring the quality and throughput of mouldmaking. To ensure that it has a positive impact, one has to consider 6 major factors, including but not limited to: spatial plane function, contour deviation and detection, compatibility with a linear encoder or any digital encoder, vibration detection and mitigation, operator flexibility and user friendliness, and lastly, automatic adjustment of feed rate and tool speeds. 

Want to learn more about our CNC controls? Contact us at Walker Machinery today at 905-876-0890. As a proud distributor of CNC controls, we also supply DRO units, digital encoders and more. Get in touch with us today to know more!