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Does copper wire work well for heating coil?

I want to make a diy hair dryer (https://youtu.be/NyXi30acGO0) however the heat coil is a tricky part. I have seen that video saying you need 32 AWG nichrome wire; and another video similar that uses 25 AWG nichrome wire. 
I got an old long ethernet cable, however it uses 25 AWG copper wire. 
Does anyone know if copper wire will work well for heat coil?

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bwrussell11 days ago

Copper will not work well, or at all really. The reason is resistance, or lack thereof. Copper has low resistance, which is why it's used for wiring, and so it won't heat up significantly without absurd current draw.

In fact, under no circumstances should you use copper wire as a heating coil. If you're pumping enough current through your coil to heat it then you're drawing enough current through your house wiring to heat it too. You'll burn your house down.

It appears nichrome 80/20 is the way to go.

ADRIANT28 (author)  bwrussell10 days ago
Thanks. But do you know what I can take apart to find nichrome wire?

I suggest taking apart an old hair dryer.

;-)

Something else with a heating element. Not sure it's used for much else.

Yea a toaster.

Toga_Dan8 days ago

in increasing order of resistance:

Copper

Steel

Stainless steel

NiCr

ADRIANT28 (author) 10 days ago

Ok Thanks for all the comments! And yes I have an old toaster to take apart. I hope my mom hasn't thrown it out yet.

The secret to understanding heating elements, is to think of the heating element as a resistor, as imagined by Ohm's law,

V=I*R

And also consider the formula for electric power,

P=V*I

The usual first step in designing a heating element is to have some number in mind for power dissipation, P, like, for example, P= 100 watts = 100 W.

The next step is to have a voltage source in mind, like for example, a 12 volt DC supply, so V = 12 V DC

Then figure out what size resistor R would be needed for dissipate P watts of power, when a voltage of V volts is across it. In other words, solve P= V^2/R, for R.

R = V/I = V/(P/V) = V^2/P

For V=12 V and P = 100 W, this is

R = V^2/P = 12*12/100 = 144/100 = R = 1.44 ohm

The next step is to think about building that resistor from a length of wire. The wire has resistance proportional to its length, and the value of that constant of proportionality is different for different wire thickness, and different kinds of metal (e.g. copper versus nichrome). This number for resistance per unit length is a number you can look up in a table.

There are other considerations too, particularly if the wire is going to get really hot.

Generally speaking, chemical reactions between solid metal and air are slow at room temperature (think "rusting"), but a lot faster at glowing hot temperature (think "burning").

For some reason, nichrome wire can survive glowing, orange hot, temperatures in air, without burning itself up.

But this is NOT the case for copper wire. So copper wire is only good for heating elements that get warm, not glowing hot.

Moreover when you do the math for finding the length and thickness (or AWG) of a copper wire needed for a particular resistance, e.g. R =1.44 ohm, it turns out you need a very long piece of very thin wire.

In fact, it might be the case that the volume of the wire, equal to its length times its cross-section area, L*A, is a number bigger than the physical space you want to heat.

I remember one time I took apart an electric blanket, and its heating element was, what appeared to be, a really long length (like 10 meters) of really thin (like 32 AWG) copper wire.

I think that was the last place I observed, in a product found in the wild, an instance of a heating element intentionally made from copper wire.

seandogue10 days ago

short answer, it is not an effective material for heat coils.

Copper will not work well as a heating element; to little resistance and to low of a melting point.