How to Get Copper Out of an Electric Motor

Before you pick up a hacksaw: we buy electric motors whole, as their own grade, on the copper winding inside. For most motors, taking them apart by hand takes a long time and rarely pays for the effort. This guide shows where the copper is and how it comes out, so you can decide.

Where the copper is

An electric motor has two main parts. The stator is the fixed outer part inside the housing, and in most motors that is where the copper is: coils of enamelled copper wire wound through slots in a stack of thin steel plates. The rotor is the part that spins in the middle.

In the induction motors found in pumps, fans and workshop machines, the rotor usually has no copper wire: it is steel with aluminium bars cast through it. In power tools and some appliances, the rotor is wound with copper too.

Some motors are wound with aluminium instead of copper. Scratch a winding: copper shows reddish under the enamel, aluminium shows silver.

Why most people bring it whole

• The windings are varnished in and wedged into steel slots. Getting them out means cutting every coil at one end and driving them out the other.
• Stripped winding wire still has its enamel coating, so it is not bright copper.
• You are left with a steel housing and core to bring in anyway.
• We recover the copper mechanically, which gets more of it out, faster.

If you do want to take one apart

1. 01Make sure it is disconnected. Many single-phase motors have a capacitor on the housing, which can hold a charge. Leave it alone or have it discharged properly.
2. 02Undo the long through-bolts and take off the end caps.
3. 03Slide the rotor out.
4. 04At one end of the stator, cut through all the coil ends flush with the steel, using a cold chisel or a hacksaw.
5. 05From the other end, drive the coils out of the slots.
6. 06Wear eye protection and gloves. Steel plates and cut wire ends are sharp.

Bring the winding wire in its own bag, and send us a photo first for the grade.

What to bring instead

Whole motors go in the electric motors grade. Large industrial motors and generators are bought as LGEM, fridge and air conditioning compressors as compressors, and car starters and alternators as a grade of their own. Take off attached pumps and gearboxes if they come off easily, and drain anything oil-filled.