Cut just about anything with this combination lathe and wire EDM

They say if you have a lathe, you also have all the other machine tools. To some extent this is true - you can make almost anything on a lathe, including another lathe, and even the best made parts on other machine tools can usually be made on a lathe by a wink. But after seeing this lathe attachment for a DIY electric discharge machining tool, we might be inclined to see EDM as the one machine tool to rule them all.

Now, we'll admit that the job [BAXEDM] built this tool for might be a bit contrived. He wanted to make custom hex inserts for his Swiss army knife, which seem to have been fairly easy to make from hex bars in a conventional lathe. Again, hardened steel is the type of material that wire EDM was designed for, and there seem to be many use cases for an accessory capable of spinning a part against a cutting wire EDM.

That was really the trick of this build: rotating part underwater. To do this, [BAXEDM] built a rig to carry a tread block that supports a standard ER-25 collet, with a bracket that holds a stepper out of the water in the EDM cutting tank. There are also plenty of 3D printed insulators, to keep most accessories electrically isolated from EDM current, as well as exotic parts such as ceramic bearings that won't corrode underwater. There were also a ton of other considerations; [BAXEDM] goes through the long iterative design process in the video below, as well as taking its new tool for a literal spin starting around 27:00.

If you're intrigued by what EDM can accomplish, and who isn't? - but you need more information about the process, we've got you covered.