Make a carbon arc torch for your 220 volt stick welder

MIG welders can do many things, but they cannot heat metal for bending or brazing. Your stick welder can do those things with a carbon arc torch added to it. 

I am using a torch already fully constructed, so you will not see the parts aside from their place in the final unit.

Materials needed:

2 pieces of 1 x 2 firring strip 6 inches long (each)
2 pieces of 1/4 inch steel rod 7 inches long (each)
2 1/4 inch water pipe nipples 2 1/2 inches long (each)
2 #8-32 thumb screws about 1/2 inch long each
2 #8-32 nuts
2 1/4 inch flat washers
2 pieces of steel 1/8 inch thick and 3/8 inch x 3/4 inch
2 crimp-on connectors for #10 stranded wire
2 #8 terminal screws from an old electrical outlet
1 compression spring about 1/2 inch in diameter and 2 inches long
1 nylon cable tie about 6 inches or more long
8 #8 round head wood or flat head sheet metal screws
20 feet of #10 stranded plastic or rubber covered copper wire
2 pieces of scrap steel or aluminum 1/16 to 1/8 inch thick and 1 1/2 x 1 1/2 inches (each)
1/4 inch carbon rods (Get at a welding supply house.)

Tools needed:

Wood saw
Hack saw
Drill press and bit assortment
#8-32 tap
Crimping tool for electrical terminals
Soldering iron (150 watt) or gas torch and solder
Arc welder

Begin by cutting the wooden handles from the firring strip--6 inches long each.

Step 1 Make the wooden handles

Cut two pieces of 1 x 2 inch pine, like a firring strip. Make them 6 inches long each.

Comments

[difflock]

A carbon arc torch is something I've wanted for my AC stick welder......


I did have an idea though.....

a couple of cheap stick electrode holders fixed together with a hinge and a spring.....

you then have a slightly more refined carbon arc torch! :)

[Phil B]

Your version will be more expensive to make and will be heavier for your hand to hold and control.

[difflock]

I know it would be a bit more expensive to make (the cheap electrode holders are less than £10 each)....

http://www.thewelderswarehouse.com/Welding/200amp_Crocodile_Type_Electrode_Holder2.html

I dont know if they are more expensive in the US though......


but apart from a hinge and a spring of some form, its all that would be needed.......


as for the weight, I'm not sure it would be heavy......
the budget electrode holders arent heavy as most of the material is plastic......


I'm definitely going to make a carbon arc torch though.....

I'd eventually like to use it for welding aluminium plus brazing of various metals...


is it possible to simply use aluminium TIG welding rods for filler material?

aluminium welding is the one thing I always seem to need, but I currently havent got the tools to do so (I cant afford a TIG capable of aluminium welding, and my MIG is configured for steel.....)

[Phil B]

In the US I have seen electrode holders for about $15. As I remember the Pound is around $2 plus, so maybe around seven Pounds.

I have no experience with welding aluminum or with using a TIG. I have read about both and watched some videos on YouTube, but that is about all. I am not much help to you.

I would be interested in seeing a photo when you get your carbon arc torch ready to use and to hear a report on how it works for you.

[difflock]

I think I'll make up a basic one from scraps (similar to yours) to see how I get on with it....

if it works out, I'll make a nicer one (which will also allow me to correct any errors/problems)

I've never welded aluminium due to not having the right setup, and I've never used a TIG welder due to costs.....


although, I am planning an alternator welder, which will become a DC TIG welder.......

but once I've built a carbon arc torch, and had a go with it, I will indeed post an update of how I got on with it.......

[Markaw]

Is it possible to make a fairly precise cutting tool without having to crank the up welder and blow through welding rods on this type of welder? I'm looking for some fairly clean edges and not molten globs. The only option I can see is a gas setup to do the cutting. On this inst...I like the ability to heat and bend that will make some projects I have in mind a lot easier to complete!

[brandon_a_boyer]

What you are referring to is carbon-arc cutting. Essentially you use a stream of compressed air to blow through the puddle. It produces a lot of sparks and is a very messy cut.

You would be far better off using a plasma torch or a gas cutting torch.

[omnibot]

Oxy-fuel welding and cutting is one option. If you can heat the metal anough and then apply a stream of pure oxygen to it iron and most ferric alloys will burn fairly straight through. Wear heavy clothing though, it sparkles like crazy but the cuts are fairly straight. It's normally used for really heavy sheet-iron and steel at wharfs and constructionsites.

[co2wms7whcc]

Look up thermite cutting on youtube. It leaves a bunch of slag but its still crazy!

[Ilan Voyager]

The only precise methods for cutting metal: - waterjet (expensive tooling) - special saw (band or circular like the Evolution saws) for straight cuts The melting or combustion tools like plasma cutting or arc leave always molten globs to finish.

[brandon_a_boyer]

Not if the process is set up correctly. I use a oxy-propadine torce on a regular basis and it leaves a very clean edge.

[Phil B]

In regard to heating and bending steel, my wife hates my welder because my metalwork produces grit on the garage floor. Some of the grit is from slag and some is from grinding metal. I mentioned MIG welders with inert gas instead of flux. She is ready to buy one for me. But, I want to be able to heat and bend steel when I need to do so. I am not ready to give up my stick welder.

On the cutting you want to do, how thick is the steel and how much cutting will you do? I use an abrasive cutting wheel a lot for cutting. If it is relatively fine work, I use a small disc on a Dremel tool. See my Instructable http://www.instructables.com/id/Sawsmith_Radial_Arm_Saw_Enlarge_Arbor_Hole_on_a/ If it is just cut off work, see my Instructable http://www.instructables.com/id/Cut_Off_Saw_from_an_Angle_Head_Grinder/ If you need to do a lot of cutting with curves, a plasma cutter might be what you need, but those cost some money. I do not have a plasma cutter. A friend does, and he found the cheap ones are not worth the bother.

[Badgermilker]

Thank you, for the design, I think i was in to the one I built was about $11.00 U.S.
I can use it either on a 110v or 220v welder depending on the thickness of what you are trying to heat. With the 220v you can heat horse shoes fairly quick to the point of being able to twist them. Once again thank you for sharing your design.
Older tech but a good tool to have in your shop.

[Phil B]

I am sorry I missed your comment when you posted it. Your torch looks very good. I am glad you are enjoying it and it works well for you. I see you used a commercial door hinge. You set your thumbscrews for holding the rods in place fairly high on the pipe nipples. The first edition of my carbon arc torch had the thumbscrews higher, but then I discovered I could not use carbon rods once they were only a certain length. I cut the nipples off and welded on nipples slightly larger in diameter for larger size carbon rods. At the same time I put the thumbscrews quite low so I could use the carbon rods until they came to be quite short. Thank you for looking and for commenting. It is always nice to have been helpful to someone.

[ta-manie]

Hi Ive just been to an agricultural show in a rural town in South Africa.
Saw a demo of a carbon arc torch. Coudnt believe my eyes (with welders helmet on). The simplicity. It was the answer to my prayers. The catch: The demo guy yapping about having sole copy righ of some kindt. (It didnt sound right). The next killer: the price ZAR650. (almost $90). Got home, googled "carbon arc torch" and more prayers anwered.
 Cant wait to get home and start making my very own torch.
I own a 220v inverter stick/arc welder and assume it should work well.
Regards, will post progress shortly. Hold thumbs for me, guys.
Ta-Manie.
Cape Town.
 South Africa.

[Phil B]

Thank you very much for your comment.  I am very happy that this will be useful to you and save you a good deal of money.  I do not have any experience with an inverter welder, but did view a demonstration video of one on YouTube.  The key consideration will be the welder's duty cycle.  If the duty cycle on your welder is too short, it may overheat and cut out before you are able to get the heat you need out of your carbon arc torch.  it is an interesting world when a guy in the northwest of the United States can provide something useful to someone in South Africa, and both of them have never met one another.  Best wishes. 

[rimar2000]

This question is addressed to several authors of welding related instructables.
Some time ago I was excited with the possibility of constructing a spot welder, but here in my city there is no way to get an used microwave transformer: nobody throws away something as that.
Then I tried with my 220-volt electric welder, but I could hardly weak solder some iron wires of 2 mm, even though I was a good time trying.
Today I decided to uncover my welding machine, and found that in the secondary winding there is no place to put even a loop of thin wire. But in the primary, yes!
I think I can easily add several turns of thick wire, by way of a "bis" secondary winding. Now come the doubts, and related questions: whether the primary winding has 248 turns (more or less, it is what I could count), and get 220 volts, it is assumed that each round of "my" coil will produce 220 / 248 = 0,887 volts. What for me? Put only one or two turns, or try to reach five or six? A more laps, more volts but less amps. I suppose that losses play an important role in the case of small voltages, and who knows what is best.
Maybe you has an answer and save me the work of trial and error, which can become very tedious. Thanks in advance!

[Phil B]

Osvaldo,

There are a number of pages in English on transformer design with all sorts of formulae.  I do not know what is available in Spanish. 

A friend had a spot welder and its transformer quit working.  We think there was an internal short in one of the windings.  I do know the secondary was not made of wire or cable, but a continuous flat sheet of copper wound with an insulation layer around itself.  They used copper sheet in order to carry the high amperage load. 

[rimar2000]

Oh, that is a good notice for me! I could use a flattened copper pipe, wrapped with a plastic hose.

Today I went figuring out, and in my small town there are not many alternatives to choose cables. There was one of section 25 mm and another 16 mm (5 mm copper diameter). I chose the latter, I'll do the test and if it is too scarce, I will buy the other.

I can read and understand fairly well English, when I encounter a word I do not know or do not remember, I go to Google translator. But I think my experiment don't deserve to study the fundamentals of transformers, it is a simple test.

Thanks for your response, I will let know to you the results.

[Phil B]

Some transformers use sheet aluminum in place of copper.  We have rolls of aluminum sheet about 10 inches wide and perhaps 25 feet long that is sold for flashing when putting shingles on a roof.  It is used to seal around chimneys and where two sections of roof meet.

[rimar2000]

The flat sheet of metal (copper or aluminum) also was suggested to me for my brother. I'll keep it in mind if the 16mm section wire fails. The sheet can be multi-sheet, for better handling. Thanks for your kindness.

An interesting warning that my brother gave me was that the construction of the clamps must be very strong, because usually there is a tendency to deviate when squeezed hard.......

[Phil B]

I remember the clamp arms from the spot welder my friend had.  They were a copper alloy tube about 25 mm in diameter, maybe bronze.  They were strong.  I think you could use steel.  If you are worried about extra electrical resistance from the steel, you could run a copper cable parallel to the steel.  The steel would provide the strength and the cable would provide the electrical pathway.   Also, the hinge system was very precise and sturdy.  Normally I would say ordinary door hinges would not work, but look at what I did with two hinges set apart from one another in this Instructable.  Setting two ordinary hinges apart makes a more precise hinge system.

[rimar2000]

I am thinking to make an welded isosceles triangle of iron tin tube (the pipe that is used for electrical wiring) approx 5/8 or 3/4 inches diameter, and use the basis side (approx 5 inches) as hinge. Higth approx 12 inches, with an horizontal hole at top, where the mobile electrode will be screwed, reversible to switch between sheet and wire solder. The fixed electrode will be flat in both cases. The axis for the triangle may be a rod of hard wood.

Very clever your Cut Off Saw from an Angle Head Grinder. I have one alike buyed cheap, it is not so strong, but is very useful to make repetitive cuttings.

[dg2clarke]

Can something like this be used to fuse-weld material which would otherwise be too thin for a given arc welder? For example the manual for my welder recommends no thinner than 1.5mm mild. Could I use something like this to weld/braze thinner material like 1.2mm without blowing holes in it?

[Phil B]

In theory the answer to your question is, "Yes."  A book on welding describes using a carbon arc to heat the metal in the same way you would use an oxy-acetylene torch to weld.  When the puddle forms, you use a steel filler rod to add material as if you were gas welding.  In practice, I see a lot of reddish residue after using my carbon arc torch.  I have concerns about it contaminating the weld.  The carbon arc is also not as precise and as easy to control as a good gas torch. 

The book I mentioned also speaks of using a carbon rod to spot weld.  I would say the two pieces have to be clamped together very, very tightly.  Then the current and the duration of the current flow has to be within narrow parameters.

I have successfully used a stick welder for material even thinner than 1.5 mm.  I held a piece of aluminum stock behind the weld to absorb extra heat and to provide a backstop so molten steel could not blow away.  I also maintained the arc only a second or two.  Then I let the weld cool a bit before striking another arc on the material.  You have to dial the current down quite a lot, and that can make starting the arc difficult.  See another Instructable I did on using a carbon rod to start the arc where you want it. 

[foxtail]

This is a fantastic instructable...here's a picture of the TCAW setup I made out of some scraps pf purple heart (wood) I had laying around (that's the real color) a marine hinge, and some 3/4" hollow shaft:

[vapoking]

I can't believe you used that much purple heart for a welder. Remember it gets darker and darker in the sun until its almost black

[omnibot]

But it's such a beautiful looking welder ;)

[Phil B]

The carbon rods will become quite hot in use. The purpose of mounting the rods on the ends of steel rods is to protect the wooden handles from excess heat. How do your wooden handles stand up to the heat in the carbon rods with the carbon rods basically mounted at the end of the wooden handles?

[foxtail]

you know, I haven't used it for longer than 5-10 minutes at a clip before. Purple Heart is extremely dense, and it has shown I tiny bit of charring, but not enough that it affects how tightly the pieces are clamped onto the wood. If I'd used pine or any other softwood though, they would have been toast by now, I'm sure. As it is, my current set up works fine for me.

[Phil B]

Sounds good. I hope you get a lot of benefit from using your carbon arc torch and really enjoy it.

[Ilan Voyager]

Many thanks. Very precise and detailed. Long long time ago, in a galaxy far far away, I've used a twin carbon torch and I've loved it for brazing aluminum. I'm going to make one as I have an old AC 130A stick welder covered of dust in a corner. The addition of a resistor would be interesting to save the welder.

[Phil B]

Thanks for your comments. I was not aware it is possible to braze aluminum. What do you use for a rod? Are there any special preparations to follow? Enjoy Instructables. I see you joined just yesterday. (I clicked on your screen name to view your public profile.) When I find an Instructable I like, I often check the author's profile to see what other Instructables he or she might have done and check out some of those, too.

[Ilan Voyager]

Since long time , Aluminum has been weld or brazed with an oxy-acetylene torch, propane torch or a twin carbon torch. Mig and Tig are electric industrial processes faster than torchs, but ask for an heavy investment (from 700 to 2000 USD in DIY, and far more in true industrial), a bit expensive for the common DIYer .

All the brazing rods for alu and white metal are zinc alloy based.

The oldest one is the Aladdin 3 in 1 brazing rod ( http://www.aladdin3in1.com/index.htm) they have very good infos and booklets. There are a lot of other brands, some with extravagant claims and outrageous prices.(alumiweld, durafix, etc).

After you have true welding with aluminum wire and a flux ( http://www.tinmantech.com/html/aluminum_wire_flux.php ).

These technics ask for a good training and can be very disappointing for the "brutal" guy. That need some brain juice and light precise hand. Preheating and cleaning are essential.

Make a search by Goggle, you'll find useful links.

A good twin carbon torch can be very useful as it doesn't contaminate the brazing or welding, and doesn't need expensive tanks. But it asks for a lot of precautions: good gloves, fully clothed, and at least a 13 shade full face mask (the electronics masks for TIG and MIG are perfect).

[Phil B]

Thank you for the response. I think I did something like that a couple of years ago. I got some special rods at Home Depot. I used a MAPP gas torch. You were to heat the aluminum and clean it quickly with a wire brush. Then you melted the rod into the joint. It seemed to work pretty well. My wife has a fondness for sundials. I designed and made one for her with aluminum rod and some aluminum flat stock bent into a circle. I had also found a web site that gives you the proper angles for the radians at your latitude.

[Ilan Voyager]

I'm a bit late, very interesting things the gnomons (solar clocks) There is an excellent freeware (versions in french, english and other languages) for conceiving and drawing a sundial that works (mine is precise at the minute)...
http://pagesperso-orange.fr/blateyron/sundials/shadowspro/fr/index.html

And do not forget the classic Roman citation on the sundial:
Vulnerant omnes, última necat (All (hours) wound, the last kills). Maybe a bit harsh in times of frivolity...

For those interested by engineering and Roman civilisation, make a search about "roman concrete" and you'll be very amazed...

[n8997j]

Yes, I did notice the power dropping off and that's what concerned me (along with the buzzing noise). I'll stick to AC and a larger flame as you suggest. I thought any sizable gap would provide enough resistance to keep the welder from overheating (like any welding rod at 50 amps). Apparently carbon gouging rods are more conductive across the gap. Thanks!

[Phil B]

As you are probably very much aware, when the duty cycle of a welder comes to be exceeded, the power at the arc takes a big nose dive. So far, that has been a good indicator to me that I need to let the welder rest and cool, or that something I am doing is causing it to overheat.

[n8997j]

Great Instructable! Using gouging carbon rods (the only kinds available), I began playing around with flame size -- very soft. My concern was the sound my DC welder made. Smaller arcs made my welder buzz like a closed circuit, similar to a stuck welding rod. Larger arcs made less buzz, but it was harder to maintain the flame. Am I burning up my welder by what seems to be creating a closed circuit using a more stable smaller arc? It sounds very much like a sustained stuck rod. Thanks for any advice.

[Phil B]

I have used AC current only with my carbon arc torch. I do not try for a small flame and have no trouble maintaining a flame, as long as the tips of the carbon rods are properly aligned and burning evenly. I would prefer my welder does not sound like an electrode is stuck. I would think the welder would overheat if running with a shorted condition like that. Previous experience with an AC welder indicated the welder's output drops off when it overheats, and that is a big signal to let it cool with some rest time. Perhaps someone else can give you better advice.