Powercore Brings EDM Sheet Metal Cutting to the Desktop
The new Rack Robotics Powercore, now on Kickstarter, brings EDM (electric discharge machining) to the desktop.
Thanks to the overwhelming popularity of 3D printing, we've seen a race to bring more automated machine tools and fabrication methods to the hobbyist community. Laser cutting is a good example. Like 3D printing, it used to be out of the budget of hobbyists. But now you can get decent laser cutters for a few hundred dollars. Unfortunately, those laser cutters do not have enough power to cut through metal. That's why the new Powercore desktop EDM (electric discharge machining) machine is so desirable, because it can cut through sheet metal.
Powercore, by Rack Robotics, is currently on Kickstarter with a modest funding goal of $5,000. The campaign has already raised almost triple that amount, which proves how excited the hobbyist community is about this capability. Until now, there simply wasn't any way for hobbyists to cut sheet metal at home without dedicating a lot of space to a large machine and spending a lot of money on that machine. Some low-cost CNC routers are advertised as being able to cut aluminum, but the results are almost never satisfactory. EDM solves this problem.
EDM works by pulsing sparks between two electrodes. With sheet metal in-between the electrodes, the sparks remove material. By move the electrodes around the material at a relatively slow pace, an EDM machine can cut thin lines. Traditionally, EDM's primary application is cutting hard metals (like tool steel) that would be difficult for conventional mills to handle. But it is a fairly clean process that doesn't require powerful motors, as there is no physical contact between the tool and the material and therefore very little torque needed. That makes it quite suitable for desktop use, because the machine can be small and lightweight.
At first glance, the Powercore EDM machine looks like another Creality Ender 3D printer clone. That's because you're meant to start with a 3D printer and then retrofit it with the Powercore power supply and electrodes. You'll remove the heated bed and an extruder, then replace them with the Powercore dielectric fluid vat and an electrode tool head.
The vat is quite small and the standard material stock is 3x3" aluminum sheet. Rack Robotics says they've successfully cut material as thick as 4mm, but recommends staying below 1mm. Cut rates are about 10mm per minute.
Therefore, the Powercore isn't suitable for cutting large sheets, very thick sheets, or fast jobs. It is ideal for small, thin, aluminum sheet metal parts that require precise, clean edges. It is also perfect for delicate parts that would be difficult to fabricate with conventional methods without damage. If that fits your use case, then there likely isn't any easier or more affordable way to make your parts.
If you want a Powercore EDM machine, the Kickstarter campaign will run until April 1st (no, it isn't an April Fool's Day joke). The Kickstarter Special price is $399 and that package includes the power supply, ten brass electrodes, 10 pieces of aluminum stock, two electrode holder kits, and a work holding kit. The user will need to print some parts themselves to finish the build. Rewards should ship to backers in July.