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12 volt soildering iron? Answered

I am looking for a cheap dependable way to make a no more than 13.8 volt D/C soildering iron that can be powered by the common cigeratte lighter plug or with clips on to the battery terminals any ideas?


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Best Answer 10 years ago

You'll have to calculate how much heater wire to put in it.  Radio Shack used to have one in their stores and I'll bet someone still does if you look for it.


Answer 10 years ago

And using ohm's law (V=IR) and (P = I2R)

A small electronics soldering iron is 10-40 watts...

You want to run at 13.5ish VDC, plan on 14V to be safe.
You want ~20 watts for small stuff
20 watts at 14 volts is (20/14) = 1.428Amps
V = IR
14 = 1.428 * R
14 / 1.429 =  9.797 ohms.

You need a heating element that is about 10 ohms rated for at least 20 watts, preferably more.