here is the model i have for the pedal. here
I made this whole thing out of just a sewing machine pedal and some wire. it is able to solder up to 14 gauge wire. this will take about an hour to build and it will cost however much you pay for a sewing machine pedal. (there cheap). i used a broken one.
The second you make a connection between the solder and the two electrodes, it instantly sucks the solder on to the wire and will NOT come off! yes, this does have the same concept as Coldheat but is way better. you don't have to hassle over making a connection. it is also way more powerful.
By the way, those sewing machine pedals are filled with carbon plates and electrodes, dont throw them away!
Below is a video of it in action!
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Signing UpStep 1Materials and tools
Materials:
sewing machine pedal
16 gauge wire
electrical tape
alligator clips (3)
Carbon rod 9i took this from a dry cell battery)
a piece of metal
L.E.D. and its power supply
12v 4amp power supply.
Tools:
Pliers
Scissors
Solder
Wire Strippers
*********** Before you start, you must take apart your pedal. open up the back, and you should see a concrete like block. crack that open and you will hit the mother load of carbon. you need the carbon and the spring.
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but you have to wrap the soldering wire around the connection?
All sizes of carbon-zinc have carbon rods in them. C and D cells have some nice thick rods.
A 12V car battery can put out hundreds of amps into a short like this, causing the carbon to glow red hot and throwing out burning lumps of metal and creating lots of UV.
Think about "Cold Cranking Amps". That is the current rating of your battery at its worst, when it is very cold, and into a starter, not a short. Well, not a total short, the carbon rods have some resistance, but not much.
What you've built here is a home-built version of the resistance solderers used by manufacturers. I think Boeing uses them.
However, be very cautious about soldering semiconductors. If the wires being soldered are making good contact, it should be fine.
This type of solderer is great because it dumps the heat right into the connection, and as you've pointed out it has zero warmup and is cool in between.
To clarify, I was never trying to say that this is dangerous with normal caution. As you pointed out, 12V won't push much current through unbroken skin, and the current would all run through a finger caught in it. You'd have to push hard enough to break the skin, at which point, shock or no, you'd yank your finger out. The biggest hazard from shocks is secondary injuries.
I would wear goggles if you don't wear glasses already, just as you should be doing when using a soldering iron. I've known a few techs who thought it would never happen to them, then it happened and they ended up wearing an eyepatch and being in a lot of pain.
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