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Posted By Dave Kari, Director of Wire EDM

In the manufacture of precision micro components 1mm and smaller – with complex geometries and critical features down to 0.1mm – the tooling and parts are only as good as the wire electronic discharge machining (EDM ) capability.

The art and science of setting wire on a path to achieve the otherwise-impossible has long been the answer to challenges traditional milling or grinding can’t accomplish. That’s how .008in and .010in wire became the popular go-to solutions. Then we downsized to .002in and .004in wire. Today, with miniaturization driving a very real need to tame highly challenging .0008in cutting, micromanufacturing often is only as good as very small-wire EDM programming.

Life on the .0008in wire is like taking part in outrageous, game-changing science. In the micromanufacturing context – especially as production continues sub-micron – today’s routine, EDM-powered advances weren’t imagined just a few years ago. When someone is skeptical that it’s possible to precision microstamp “something that small and complex,” the explanation includes what small-wire EDM evolution has done to advance tool engineering and building. Like the ability to maneuver through a workpiece with a material thickness-to-thinnest-feature ratio that comes in at 25-to-1.

Amazingly, NC programming that makes a wire so capable starts with just three G-code commands: proceed straight, clockwise or counter-clockwise. Plus some algorithms and CAD/CAM power. But there is a non-math element also critical to small-wire programming: on-the-part experience.

Here are a two things I know about balancing on the small wire:

Learn to see what the wire is going to see. By assembling the best theory on what will occur. What did the outcome from the last wire execution tell you? You can’t always know for certain what caused a failure, but experience gradually builds a pre-routine menu of indicators, variables and scenarios that help you anticipate what the wire and the machine will encounter. And what will result.

Personal discipline is key. Small-wire EDM programming is a lesson in patience and intestinal fortitude. Sometimes it takes multiple re-programs in order to complete the optimal, most effective path. Especially on ultra-complex micro and micro-miniature projects. It requires “wire path forensics” and deductive reasoning. Execute your theory. Cut the sample part. Determine how to compensate for what you observed. And then repeat the process again. Eliminating errors until none remain.

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