Electro Arc

How to size an electrode

Selector Charts for AC/DC and Bolt Eater Metal Disintegrators for converting tap, drill and bolt sizes to electrode size needed. Selector Charts also have recommended machines power settings for the each size electrode.

Please note: You may add the electrodes to your cart and request a quote.  



For Removing Taps:

  • Select an electrode that half the tap diameter.
  • Remove tap core and flutes with magnetic picks


Method #1 – Bolt Removal

  • Select an electrode that is 70% of the drill tap size or 65% of the bolt diameter
  • Remove bolt shell with Easy Out.


Method #2 – Bolt Removal

  • Select an electrode that is closest to the drill tap size minus .020″ or .508 mm for over burn
  • Clean out bolt hole with starter tap


Method #3 Bolt – Removal

  • Select square electrode that is closest drill tap size minus .20″ or .508 mm for over burn.
  • Back out bolt shell with square ratchet or push sides inward and remove.


For Removing Dowel Pins:

  • Select an electrode 60-70% of the Dowel diameter
  • Twist dowel pin out of hole using an Easyout


For Removing Drill

  • Select an electrode that is closest to 60% of the drill diameter
  • Graphite Electrodes do not come in all diameters so selecting the next smallest diameter will usually work.

Molybdenum (Moly) Electrodes

Moly Electrodes have a higher melting temperature which means you will erode more of the broken tool and less of the electrode making Moly less expensive to use than other materials.

Graphite Electrodes

When removing large bolts .750″ to 19 mm and up use Graphite Electrodes for optimum performance and value. Graphite Electrodes only work on metal disintegrators with 20-KVA or DC power supply.

Square, Hex, and custom Graphite Electrodes are available upon request

Electro Arc