Introduction: Carbon Arc Torch
Carbon arc torches are an simple way to generate heat using the power supply through an arc welder. It uses the arc created between the two carbon electrodes to produce heat for bending or brazing metal.
Step 1: General Componants
I did a lot of searching on Instructables and the web in general.
The general principle is the carbon rods need to be touched together and once they generate a glow and some heat parted slightly to instigate the arc.
Almost all examples I could find used a BBQ tong style handle although one example which showed how to make one running directly off the wall socket used a sliding handle and this was the basis of my design.
So I needed the carbon arc rods, my arc welder and a slide which is a metal draw runner from this I layed out my setup and added parts as I saw fit.
Step 2: Rod Holder
The first part that needed to be made was the holders for the rods,
I wanted to use the stinger (electrode holder) for the arc welder as my main base and have the other parts detachable in order to use some or all parts as required.
My arc welder came with a spot welding attachment so I used a short length of steel tubeing that I ran a drill bit through to clean and make the correct size to take the carbon rod and an 3mm set screw which was spot welded together this then is held with the electrode clamp.
Step 3: Rod Clamps
To make as much of my torch serviceable most parts are bolted together in some way.
To clamp the rod in place I drilled a 17mm AF nut to the size of my rod tube I then cross drilled it and through the tube and threaded the side hole in the nut to M4 and clearenced the hole in the tube and using a little M4 stud bent to 90 degrees was used to lock the rod in place.
I made a second holder tube and clamp to go on the end of the draw slider I spot welded it on at an angle that looked about right while I mocked up I then used the single carbon electrod rod in the stinger and using tig brazing rod added some extra strength to the join as I didn't want a very hot rod falling off if I caught it while working.
Step 4: Handle and Slider
After a false start or two I found a quick detachable way to mount the slide assembly to the stinger in the form of an old bicycle D lock bracket used to hold your lock to the frame while riding it has a cam lock lever and a slot for the shackle.
The slot fitted nicely around the electrode clamp lever and with a little duct tape the diameters matched fairly well.
I used a couple of self tapping screws to hold the slider to the center web of the lock clamp and a M4 nut and another but of studding to make a screw lock so the slider could be locked open and keep the rods apart so I could put the torch down without it creating an arc accidently.
I left the frame loop of the lock mount on putting a couple of small bolt so it could be use to hang the torch if needed.
Step 5: Testing and Storage
I had wished not to use any extra wiring and clamp the earth directly to the slider but in practice I found that the added weight to an already bulky bit of kit was too much and added heat to the slider so using the old earth wire from my mig welder which I had replaced recently I clamped one end to the slider with a screw, washer and nut passing it through the detachable clamp and cable tieing it to the other end of the slider so it could not pull the slider back into contact with the other rod, this also added a little exra length as the earth lead on the arc welder is shorter than the stinger lead.
After making some light and noise and then letting the torch cool down all the parts can easily be disassembled and put away for another day.
Step 6: Safety
Any welding using electricity is dangerous and you shold take all the precautions and wear the correct clothing and protective equipment the arc produced with a carbon arc torch will cause serious burns to your skin and eyes!
Take it seriously or you will need someone to take you to hospital.
This torch also involves live current do not undertake if you are not competant.
You are responsible for your own saftey not me.