Open Source Die-Sink EDM Machine

Basics

• Part of the Open Source Digital Fabrication Construction Set
• An electric discharge machining device (EDM)
• Uses a die, and high voltage electricity to precicely erode away material using the resulting plasma

Used For

• Mold Making
• Die Making
• Machining Difficult Metals Like Tungsten
• Hole Drilling (Especially of very small holes, or on difficult materials and/or geometries (such as drilling through a sphere) )
• All of this with very high tolerances

Industry Standards

MC Machinery

• Their Site

Sodick

• [Their Site]

Makio

• [Their Site for RAM EDM]
• [Their Site for EDM Hole Drilling]

Existing Open Source Designs

"Scorch Works"

• [https://www.youtube.com/watch?v=-a1JEWbnvMo A Video by the YouTube Channel "Scorch Works" Titled "EDM (electric discharge Machining) Machine Walkthrough"
• The Hackaday Article on their Design
• Their design utilizes largely salvaged components, it uses a Clothes Dryer Heating Element as the stabilizing resistor, Microwave Oven Transformers etc
• They do mention a Hand Traced PCB although much of it's functions can be largely replaced by an Arduino or Universal Controller etc
• It is a die sink model, but does have the option to flow water down the linear actuator to the toolpiece

Dedicated DIY EBM Website

• Site Link

"Alchemist Dagger"

• An Instructable Showcasing a Design by "Alchemist Dagger" (It utilizes a rather poor motion system, but the electronics showcase the potential for an ultra-simple EDM Power Supply

"My engines"

• A Video by the YouTube Channel "My engines" Titled "Building a PULSE EDM with the DIY book of Ben Fleming Part 1"

Basic Design

Housing

• Holds all the below together

Controller

• Controls all components
• Raspberry Pi + Arduino + Any necessary shields?
• Connects to IO Panel and any external controls (PC, Server, WWW, etc)

IO Panel

• Touchscreen
• Optional Mouse + Keyboard

Fluid Pump

• Recirculates the dielectric fluid
• Does this to promote circulation
• Also provides pressure to debris clearing jets

Fluid Filter

• Cleans Debris (Such as Metal Dust) Out of the Dielectric Fluid
• Hydrocyclone + Standard Oil/Water Filter Cartridge
• Should also include sensors before and after filtration to determine fluid + filter effectiveness

Work Surface

• The Workpiece is attached to this

Fluid Bath

• Allows the Work Surface and Work Piece to be submerged in dielectric fluid
• Could be permanent or a slide up design

CNC Gantry

• Holds and Moves the Toolpiece
• Standard D3D Axis?

Toolpiece

• A Hollow Cylinder (Similar to a drill chuck) that allows various sinkers to be attached
• Works with the power supply
• Quickchange optionally

Fluid Reservoir

• Holds Spare Fluid
• Also holds the contents of the fluid bath when not in use

Fluid Filter

• Filters out the debris from machining (Such as various metal dusts and chemical powders created
• Then Keeps the fluid at the sort of "Goldylocks" like position between deionized and tap water (Most likely using a PEM and/or a dillute and dump (Add in DIW dump out some of the "spent" fluid)
• Will also need sensors to monitor that it is working effectively

Internal Links

• EDM

External Links

• Wikipedia Page on Electrical Discharge Machining