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TURN AN OLD ENDER 3 INTO A WIRE EDM THAT CUTS METAL WITH SPARKS

A brass wire thinner than a paperclip cuts through tungsten carbide and hardened steel with electrical sparks, and an old Ender 3 becomes the motion platform.

by Almost Completed Projects

FULL CAD BOM FIRMWARE DOCS

WorkshopOpen-hardware

Built withRaspberry Pi Pico / RP20403D printing

difficulty
●●●●●
time
a weekend-plus
license
CERN-OHL-S-2.0
repo
repo ACTIVE130 stars

WHAT YOU’LL NEED

Videos
1
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COMPAREE VERDICT

EnderSpark is a real wire EDM built on an Ender 3 frame, and the electronics parts list, PCB files, mechanical models and a detailed README are all published. Wire EDM cuts conductive metal - brass, steel, aluminium, even tungsten carbide - with electrical sparks in a dielectric bath, so there is no cutting force. The conversion keeps the Ender 3 motion system but converts X and Y to lead screw plus 1:3 belt reduction because EDM cuts slowly and the steppers on their own are far too fast. A Raspberry Pi Pico with a TC4428 gate driver and MOSFET switches up to 10 A at 60 kHz. Parts come to roughly 250 EUR plus four machined components and under 50 hours of work, per the author. There is no step-by-step assembly manual yet, so expect to combine the README, the STEP files and the video with your own machining and high-current experience. The voltage in a wet conductive tank is above safe extra-low voltage and should be treated as lethal, copper waste must be disposed at a recycling centre, and the machine emits strong EMF. This is for people who already work with high current and have access to a lathe or milling machine. It will not hold the tolerances or duty cycle of an industrial machine. The README links a Discord for builders.

GOOD TO KNOW

  • —STEP files for mechanical parts, Gerbers and schematics for the PCB, firmware configuration for Ender 3 V2, and an SVG for the laser-cut water tank are all in the repository.
  • —The electronics BOM is published, but four machined parts are required and the repository does not include drawings or G-code for those — you machine them from the STEP files or source them yourself.
  • —There is no step-by-step assembly guide yet; the README covers the wire feeder and tension (about 18 N for 0.25 mm wire), the filtered deionised-water loop, firmware changes and toolpath generation.
  • —Licensed CERN-OHL-S v2 (LICENSE file in the repository).
  • —The project assumes you already know high-current electronics, EDM principles, and CAM workflow — it is not a teach-yourself-from-zero build.

Parts to buy

11 items

From our check of the build. Exact quantities and part numbers are in the creator’s BOM.

  • Ender 3 (donor)Find
  • Two 1:51 gear reductions (lead screw plus belt reducer)Find
  • Raspberry Pi PicoFind
  • TC4428 gate driverFind
  • MOSFETFind
  • Passivesfrom the repo files
  • PCB fabricationFind
  • Brass wireFind
  • Dielectric fluidFind
  • Laser-cut acrylic sheet for water tankFind
  • Four machined parts (lathe or mill required)Find

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Can I build this?

PrintAbout 200 g of PLA for brackets, the water nozzle and spacers (STEP files in Parts/Printed parts).
BuyEnder 3 (donor), two 1:51 gear reductions (lead screw plus belt reducer), Raspberry Pi Pico, TC4428 gate driver, MOSFET, passives per BOM, PCB fabrication, brass wire, dielectric fluid, laser-cut acrylic sheet for water tank, four machined parts (lathe or mill required)
Toolslathe or milling machine to make the four machined parts, soldering station, multimeter, oscilloscope (strongly recommended for tuning pulse timing), basic hand tools
Skillsintermediate-to-advanced machining, intermediate electronics including gate driver circuits and high-current switching, CAM workflow (Fusion 360 post processor is included), EDM principle knowledge, and comfort working with lethal voltages in wet conditions
Timeunder 50 hours including machining the four parts, assembling the mechanics, building and testing the electronics, and first tuning — more if you are learning EDM principles or debugging pulse timing
Cost$$$ by our scale: the author puts it at about 225 EUR without the printer (electronics about 50 EUR, power supply about 50 EUR, mechanical parts about 115 EUR, water management about 80 EUR), plus the donor Ender 3 and four machined parts
SafetyLethal risk: 48-110 V DC from the arc supply in a conductive water tank (above safe extra-low voltage when wet), strong EMF emissions (relevant for cardiac devices), and copper-laden waste water that must be evaporated and disposed at a recycling centre, not poured down a drain

Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.

Videos

Ender 3 to Wire EDM, how to cut metal with a 3D printer

The creator's own video 'Ender 3 to Wire EDM, how to cut metal with a 3D printer'. The README presents it as a short tutorial on the toolpath workflow; a complete tutorial is announced. Use it together with the detailed README.

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Gallery

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Start here

Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.

  1. 1.Read the README, then watch the video (The README is the written reference; the video shows the machine and toolpath workflow. A full tutorial is announced.)
  2. 2.Check the BOM and verify you can source or machine the four unlisted parts (STEP files are provided but not machining drawings)
  3. 3.Order the PCB from the Gerbers(schematics are in the repo — review them before ordering)
  4. 4.Plan dielectric circulation and wire tension (The README covers the wire tensioner (about 18 N for 0.25 mm wire) and the deionised-water loop with pump and filter.)

Resources

Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.

KNOWN ISSUES

  • The repository does not include machining drawings or G-code for the four required machined parts — you work from STEP files or find a machine shop that will.
  • There is no step-by-step assembly manual or tuning guide yet (the creator says a full tutorial is coming), but the README explains the wire feeder and tensioner, the water loop and dielectric, firmware changes and Fusion 360 toolpaths.
  • The hardware is licensed CERN-OHL-S v2, a strongly reciprocal licence: you can build, modify and sell, but modified designs you distribute must be published under the same licence.
  • The reduction is a T8 lead screw plus a 1:3 GT2 belt stage on X and Y. The parts are cheap, but the creator notes the anti-backlash nuts still leave some backlash.
  • The electronics assume you already know gate driver circuits and high-current MOSFET switching — if you have never tuned pulse timing on a scope, this is the wrong first project.
  • Copper-laden waste water cannot go down a drain — you need an evaporation and recycling disposal plan before the first cut.

Can I use a different 3D printer as the donor?

Yes, the principle works on any motion platform with enough travel, but the firmware configuration and mounting points are specific to the Ender 3 V2 — you will need to adapt both.

What is the thinnest part I can actually cut?

Wire EDM is capable of paper-thin cuts because there is no mechanical force, but this build's accuracy depends on your Ender 3's frame rigidity and the backlash in the reducers — it will not match an industrial machine's tolerances.

Do I need the exact Raspberry Pi Pico, or will a clone work?

The PCB and the MicroPython code are built for the Raspberry Pi Pico footprint. The README does not cover clones; a board with the same footprint and pinout may work, but check it against the schematic before powering up.

What dielectric fluid do people actually use?

The creator uses deionised water, the easiest option; ethanol, oil or kerosene also work. The README describes the filtered water loop (24 V membrane pump, 10-inch filter cartridge) and how to settle and dispose of the dirty water.

Community builds

No community builds yet — be the first, we feature the best ones.

Discussion1

FROM THE COMPAREE TEAM

Wire EDM cuts tungsten carbide and delicate parts with no cutting force, and this conversion is quoted at around 250 euros plus four machined parts and the donor Ender 3 — what would you cut first if you built one?

CompareeTEAM1mo agoedited

Practical notes from our verification: the repository publishes Gerbers and the schematic for the generator board, an electronics parts list, STEP files for the mechanical parts, the firmware configuration for the Ender 3 V2, a Fusion 360 post processor and the SVG for the laser-cut water container, all under the CERN-OHL-S-2.0 open hardware licence. The README is a real written guide: it covers the motion changes, the wire feeder and tensioner (with a target tension for 0.25 mm wire), the arc generator, the deionised-water loop and filtering, the firmware edits and toolpath generation, and the short video focuses on the toolpath step. Four machined aluminium parts are still on you, and the author notes the STEP files are not fully up to date. The X and Y axes are converted to T8 lead screws with a 1:3 GT2 belt reduction; the README also quotes 1:51 as the overall reduction, so treat that figure as the author's. The single biggest risk is electrical: the author warns the voltage is above safe limits in wet conditions and should be treated as lethal, so this is for people comfortable with high-current switching, not a learn-as-you-go build. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.

Almost Completed Projects

Almost Completed Projects publishes experimental machine conversions and open hardware builds. EnderSpark applies industrial EDM principles to a hobbyist motion platform, with all electronics and mechanical files released.

GitHub

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DISCLAIMER

  • Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
  • Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
  • Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
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