Tool Tips
March 2019
Precision machining has always been the goal of CNC manufacturers, and as technology is getting smaller, especially in the fields of consumer electronics, aviation and automotive, the shift from traditional machining to CNC machining has continued to grow. And, as it grows, the tolerance for error is getting smaller.
Customers and end consumers are demanding higher quality products, created out of new or different materials. They want more of them and they want them faster than ever before.
That leaves CNC manufacturers needing to speed up production whilst still achieving a precise level of finish that would usually be created, over time, on multiple machines with more human intervention. Their goal now is
absolute precision machining; rapid manufacturing of identical parts and components with zero variance.
Not all materials are created the same
It may seem obvious, but in the rush to produce simple things like the composition of the material being machined can be overlooked. What works for steel will not work for titanium. Aside from the high risk of variances in the product – when materials are swapped out – shops also risk catastrophic tool failure. For consistent precision machining test and adjust programs according to material composition; it may seem obvious but can be a missed-step in the hurry to get through production.
Less is more
A multi-axis machine may remove the need for multiple machines to finish a tool. Four or five axis machines mean a tool can be completed autonomously, without requiring human intervention to shift the tool between machines. The less manual handling required the better as this can small variances in the end product.
Information is power
Connected machines that give real-time feedback on status, potential issues and quality control puts the power firmly in the manufacturer’s hands. The ability to know – before it’s too late – any fluctuations in accuracy means less waste and better precision.
Beware the roadblocks
Although modern CNC machines are geared for precision machining – think multi-axis machines that are highly adaptable to materials – manufacturers are finding the journey is not without its roadblocks.
The first, and most obvious, is the cost. It’s highly unlikely to get a tool geometry correct on the first try. Multiple iterations in geometry changes are usually required, and this can be expensive. The good news is that with the right software, tool geometry can be analyzed after simulation which can replace the need to experiment with real tools – the software can predict outcomes for you. Increasingly software is able to predict, not only how to best grind a tool, but even how well that tool will perform under real use conditions.
Another roadblock is the small changes that can occur during production. The tools being ground are very, very small; the size of a human hair, or even smaller can mean a major change in the quality of the finished product. Even the tiniest shift in grinding through external vibrations can change the end result.
Tool manufacturers can now use automation to help reduce these defects by testing and measuring the tool while it is being ground, and automatically adjusting to counter any variance – before cutting, during cutting, and after, against specifications.
Automation isn’t a trend, it’s the key
It looks like automation is here to stay, and when fast, precise, high-volume machining is demanded that’s no great surprise. In fact, the global investment into process automation is expected to reach 120 billion dollars by 2019, according to a report by market analyst, Research and Markets.
Automation removes human error, allows machines to self-regulate – creating their own micro-adjustments as required – and allows shops to operate ‘lights out’ for increased output.
As demand grows for precision machining automated, connected CNC machines are making this long sought after goal an easy reality, for those manufacturers willing to set up their systems to get it right.
20 June 2019