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We wound a quadfilar coil using 3 one pound # 23 AWG magnet wire and one coil with 8 ounces of # 26 awg for the trigger. The wires were not twisted together before winding. The core is made with 1/16 inch coat hangers. Former is a plastic wire spool approx. 3 inches tall.
The wheel is running at approx. 300 rpm.