I don’t like rewinding old pickups when they are in fine working condition. I’d rather fabricate another bobbin and do a custom wind on it for the customer even though they don’t care about taking an old pickup and rewinding it, I try to discourage it so they don’t regret it later. Rewinding helps after the pickup has been butchered by a repairman that didn’t know what he was doing and you want to restore it to original conditions. You can custom wind a broken pickup for a different tone and output using different gauges of magnet wire. A pickup can be reverse wound for phasing and humbucking effects.

Always take care of an unused pickup and never leave it unprotected in a case that can bounce around and eventually become damaged or broken. I’ve seen gouged coils from screwdrivers that slipped, solder globs on coils and coils damaged from improper shielding with paint and foils. Often removing a few layers of the outer coil is enough to save a broken pickup. Remember if you break one turn of a coil the pickup will not function.