Wire EDM Machine

This wire EDM project started about 1,5 years ago. I stumbled across some movies on youtube of DIY WEDM machines which really “sparked” my interrest.
I like mechatronic projects. That is, projects that include mechanics as well as electronics. Next to that, my shop already has a CNC mill and lathe so a sinker and wire EDM would make the capabilities of my shop complete. With that in mind, I decided to do this project. Not a small decision, since this is the most complicated build that I have done so far (on my own that is). It took many hours and trail and error to get the machine up to the state that it has today.

 

The main features are:

  • 6 DOF precision adjustable work table, to calibrate the workpiece table Rx and Ry for XY plane orthogonality to wire Z. Rz is used to align worktable reference groove parallelity to the wire x travel.
  • Precision leafspring XY positioning mechanism in the upper wire guide to calibrate the Z axis orthogonality the the XY plane (making sure both wire guides exactly line up).
  • Industrial diamond wire guides
  • Custom stainless steel wire guide holders, that use industrial OTS flushing nozzles
  • Adjustable C-arc opening to get the flushing nozzle right up to the workpiece and to keep the cutting part of the wire as short as possible.
  • Very stiff TIG welded stainless steel custom frame.
  • Electrically isolated 6 DOF work table supports, that do not have materials in the interface to the fixed word that can creep. Only ceramics and metals are used
  • C-arc is electrically floating and anodized to minimize electrochemical corrosion.
  • Full ceramic zirconium bearings on all wire guide wheels (for isolation and water compatibility)
  • Quick release system for fast manual re-wiring after a break.
  • Supports large 12 KG 160mm diameter wire spools.
  • Custom long life carbon brush electrode to transfer current to wire.
  • Long X and Y strokes, over 200mm each.
  • Workpiece height up to 100 mm.
  • Advanced IGBT based arc power supply, with adjustable process parameters, frequency, current and duty-cycle.
  • Arc control electronics and powerstage separated by fiber optic cables.
  • Electrically isolated Vgap measurement, which is independant of the set process parameters (duty cycle does not affect measured Vgap).
  • Cutting wire voltage is isolated from mains.
  • Wire tension closed loop control with readout.
  • Wire feed rate closed loop control with readout.
  • Wire “mileage” gauge, to track wire spent.
  • Adjustable even re-reeling of spent wire for easy disposal or possible reuse.
  • Water filtration system that uses industrial standard EDM filter.
  • Water deionisation filter.
  • Separated water tanks for dirty and clean water.
  • Water conductivity measurement