The Insane Accuracy Of Wire EDM Machining

One of the most satisfying sights we ever get to see is when something fits just right. I've never pulled that particular feat off when installing outlet covers. They always seem to stick out slightly, just off-center or not quite flush with the wall. Maybe nobody else notices that little imperfection, and maybe nobody ever will with things that aren't exactly at eye-level, but I know they're there. And the day I manage to get one perfectly smooth against the drywall, I will take a picture of it. I will know I have mastered that thing.

But even that won't nearly match the exacting fits created by wire EDM. What a process!

Electrical discharge machining, or EDM, uses the heat from sparks traveling along a super-thin wire to carve shapes, like this snowflake, out of metal.

It's not until you start fitting the pieces together that you realize just how accurately these pieces can be milled.

These two separate pieces of metal were machined down with such accuracy that they almost don't fit.

How close together are they? Just 0.0001", enough for air to slowly escape. It's close enough that the heat coming off your hands could make the metal expand too far.

If you look closely, you can make out the faint outline of the snowflake. 

It's a process commonly used in Tool and Die making, and it has also been adopted for aerospace and electronics parts, where fewer, more specialized components are needed. 

Learn more about EDM below!

Advertisement