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Nichrome wire

Also called resistance wire, hair dryer element, toaster wire.

Bare resistance wire, usually wound on mica in a hair dryer or a toaster. It runs at mains voltage in the donor. It will sag, oxidize, and start a fire if you reuse it without a ceramic support and a thermal cutout.

If you are new to this category

Speakers, lamps, heaters, and displays. To test a speaker, touch a 1.5 V cell to the terminals for a moment. The cone should click once. A heater can start a fire if you remove the part that was supposed to shut it off.

Heat and bright light usually mean household voltage. Unplug first. If the original safety part is open, find out why before you replace it.

A heater is a chain

Wall power goes through a switch, a one-time thermal fuse, and often a resettable thermostat, then the element. If you remove the fuse because it is open, the element can stay on after something else has already failed. That is how the donor caught fire the first time.

Mains voltage. Line voltage, and the DC bus just after the rectifier, both kill. A disconnected cord is not a discharged supply.
Heaters without their cutout. Nichrome and tubular elements are happy to start a fire if the thermal fuse or tip-over switch is left out of the new circuit.

Specification. The right-hand column is what is typical. The label on the part in your hand wins if they disagree.
What to look for	Usual figure
Form	Coiled on mica cards. The mica is part of the insulation. Do not let adjacent turns touch.
Voltage	Whatever the appliance was. A 120 V dryer element on 230 V is a brief firework.

Volts are electrical pressure, amps are how much current is flowing, and ohms are how hard the part resists that flow. A higher voltage than the part was built for is how salvage parts die on the bench. If a cell in the table says “read the stamp”, that stamp is the whole specification.

What people actually use it for

A hot-wire cutter on low voltage
Repair of the same appliance
A heater with a cutout and a real mount

Leave this one when

The wire is already broken and brittle. Old nichrome snaps when you rewind it.

Buying a new one is the better idea when

New resistance wire of a known ohms-per-metre, if you are designing a cutter. Salvage wire is a known resistance only as a complete element.

How to tell if this one still works

Resistance cold, insulation to the chassis, and a visual check that no turns are touching.

Step-by-step on the bench: Insulation-check a mains element

Tools you will want: Meter, Ceramic or mica supports.

Words on this page

Short meanings, so the rest of the entry is readable if you are not already doing this every weekend.

mains: Ordinary household wall power. It can kill. Unplug before you open anything that used it, and do not experiment on live wiring.

Where people actually find it

4 notes, most useful first. “Leave it” means the part is in that machine and you should not take it: it is dangerous, worn out, or only useful if you already know that exact repair.

Harvest at a glance
From	Call	How many	How often	Where it sits
Clothes dryer	Worth it	1	sometimes	Open-coil models.
Toaster and toaster oven	Worth it	2–4	usually	On mica cards.
Hair dryer	Worth it	1	usually	On mica.
Space heater	Worth it	1	sometimes	Wire-element models.

Worth pullingClothes dryer1 · sometimes
In this particular machine
Bare wire on ceramic supports.
Where to look
Open-coil models.
How to get it out
Do not let turns touch when you reuse it.
The condition to expect
Brittle.
Worth pullingToaster and toaster oven2–4 · usually
In this particular machine
Mains element, several hundred watts per card.
Where to look
On mica cards.
How to get it out
Keep the mica. Do not let coils touch.
The condition to expect
Brittle if it has already been overheated.
Worth pullingHair dryer1 · usually
In this particular machine
Two heats, taps on the coil.
Where to look
On mica.
How to get it out
Keep supports.
The condition to expect
Brittle.
Worth pullingSpace heater1 · sometimes
In this particular machine
Mains coil.
Where to look
Wire-element models.
How to get it out
Keep the thermal fuse in the design.
The condition to expect
Brittle.