Make a Carbon Arc Torch for Your 220 Volt Stick Welder

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Introduction: Make a Carbon Arc Torch for Your 220 Volt Stick Welder

About: I miss the days when magazines like Popular Mechanics had all sorts of DIY projects for making and repairing just about everything. I am enjoying posting things I have learned and done since I got my first ...

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.

Step 2: Prepare the Handles for the Hinge

The handles are hinged at the rear end of the torch. The side with the single screw is free to move. The 1 1/2 x 1 1/2 pieces of aluminum or steel are fastened with two screws to the other handle. The side out of view to the camera is a mirror image of what is shown here. Leave the single screw a tiny bit loose so the hinge action moves freely. (The hole you see in the aluminum is left over from a previous life.)

Step 3: Prepare the Handles for the Spring and Nylon Tie

Using the torch will involve squeezing it with one hand. You want the spring to gently push the handles open when the pressure from your hand is released. But, you do not want them to open without limitation. So, a nylon cable tie goes through the center of the spring and around the bottom of the handles to restrict how far the handles can open.

Close the handles and drill a hole about 3/16 of an inch through both. The nylon tie will go through these holes later, but not right away. Open the handles wide and drill a 1/2 inch countersink hole on the inside face of each handle. These holes are for the ends of the spring.

Wait to install the spring and nylon tie until after the next step.

Step 4: Drill the Ends of the Handles for the Steel Rods

The holes for the steel rods should be straight and parallel to each other so the tips of the carbon rods will touch when the handles are squeezed together during use of the torch. A drill press or similar assistance for drilling holes parallel to the outer surfaces of the handles is a big help, although it may be possible to get pretty close with a hand-held drill. These holes should be about 1 1/2 inch deep into the ends of the handles.

Weld a flat washer on each steel rod. Insert the rods into the handles. Drill for a locking screw on each handle. This screw fixes the rods so they cannot shift or rotate from your setting of their angle.

Now place the spring into the countersink holes on the inner surfaces of the handles. Hold the handles together lightly and insert the nylon tie so it goes through the spring. Slip the end of the nylon tie through its own retaining hole and adjust the tension on the nylon tie for the amount of space you want between the handles when they are not being squeezed. Trim the nylon tie so the extra is removed. You may want to heat the cut end of the nylon tie with a match so it loses its sharp edge. Sometimes those can scratch and cut. (See the previous panel for the photo there.)

Step 5: Weld the Nipples to the Rods

If you can get black iron nipples, so much the better for welding. If you can get only galvinized, grind away the zinc coating wherever you will be welding and do not breathe any fumes. Do your best to align the nipples to the steel rods before welding so the center of both nipples is on the same plane as much as possible. This will be important for making the tips of the carbon rods meet when the handles are squeezed together during use of the torch. Some discrepancies can be overcome by bending the 1/4 inch steel rods a little.

Nipples are a little larger than their nominal sizes. You may want to run a 5/16 inch drill bit through the nipples. This would allow using 5/16 inch carbon rods for a bit more heat, although I have always been able to do anything I need to do with 1/4 inch carbon rods. Besides, it is not always easy to find 5/16 inch carbon rods.

Drill a 3/16 inch hole in the side of the nipples near the lower end (as when the torch is in use). Place a #8-32 nut over the hole and weld it in place. The nut's threads will likely distort a little during welding. Chase the threads with a #8-32 thread tap. Screw the thumbscrews into the nuts.

A 1/4 inch carbon rod is shown in the nipple ready for use in the photo.

Step 6: Add Tabs for Electrical Connections

Weld steel tabs 3/8 x 3/4 inch to the 1/4 inch steel rods for the electrical connections. Be careful to check their position before welding so the tabs will not touch and short out the torch when the handles are squeezed. Drill each tab and thread for #8-32 screws. Brass screws from old electrical outlets work very well, although you may need to chase the ends of their threads with the thead chaser on your crimping tool.

Cut the 20 foot piece of #10 stranded wire in two halves. Crimp the connectors on each 10 foot piece of #10 stranded copper wire and attach the wire to the tabs.

Step 7: Secure the Wire

Another smaller nylon tie can be very helpful for securing the wires as they pass under the handle as you see in this photo. Use electrical tape every foot or so to keep the two wires together.

Strip the other ends of the wires back about an inch and tin each with solder to keep them from fraying.

When you are using the torch, either wire will be held by the welder's ground clamp and the other will be held by the electrode holder (stinger). There is no polarity to be of concern. Keep the electrode holder and the ground clamp separated from one another so there will be no unwanted sparks.

Step 8: Insert the Carbon Rods and Align Their Tips

You need about two inches of carbon rod extending from each nipple at the very minimum. This keeps the actual torch from becoming too hot. With the welder's power off, adjust the carbon rods so they meet each other when the handles are squeezed together. Bend the 1/4 inch steel rods slightly as necessary to insure the tips meet.

During use you will need periodically to stop and readjust the position of one or the other of the carbon rods because one invariably burns faster than the other. I find I can do this easily while wearing welder's gloves.

Step 9: Using the Torch

This is how your finished torch should appear.

Put on your welding helmet and gloves. Set your 220 volt welder between about 70 and 90 amps for 1/4 inch carbon rods, depending on how much heat you need for your job. (115 volt welders do not have the power or duty cycle needed to operate a carbon arc torch.)

Be careful that the torch does not touch anything conductive once the welder's power is on. When you need to put the torch down, you can leave the welder running, but turn the torch upside down and set it onto a piece of plywood or a clean, non-metalic workbench surface.

Flip your helmet down with the snap of your neck. Squeeze the handles together until the tips of the carbon rods touch. Hold them together for a couple of seconds so they can heat up. Then gently relax your grip just a little so the tips have a gap between them, and a brilliant blue arc will form between the tips of the carbon rods. It will be very, very hot. You will soon get a sense of how much to spread the tips.

Keep the arc moving over the steel you want to heat. If held in one place too long, little pools of molten metal will form and you could even burn or blow through your work. I find it works best to heat a small area on a piece I want to bend and then pull part of the bend I want to make. Then I heat the area next to what I bent until it is ready to pull. If something does not go quite right, heat it again and bend to correct.

If you are brazing something, heat the metal until it is hot enough to melt the brazing rod.

A carbon arc torch does not use gas flowing under pressure, like an oxy-acetylene torch. You do not need to worry much about small parts being blown out of position.

A carbon arc torch greatly expands the versatility of your 220 volt stick welder. Some people use the flame of a carbon arc torch the way one might use the flame of an oxy-acetylene torch to make metal form a pool. Then they add welding rod to weld as they would with a gas welder. I have read that it is possible to use only one carbon rod. The ground clamp goes on the work and the single carbon rod acts like a spot welder. I tried this once, but the pieces of metal were not clamped tightly enough to make it work.

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99 Comments

Hi Phil- thanks for posting , I am building one with your model, and trying to find , AC carbon rods . The welding material suppliers in my region all have DC gouging rods , Do you think these could work with my Lincoln AC stickwelder.

1 reply

Hi Phil - excellent and informative tutorial. Do you think it would be OK to use brass and copper or is mild steel required to withstand the heat generated?

1 reply

Thanks. I think you could use brass or copper. The carbon rods are supposed to extend a couple of inches below their holders. That keeps the heat lower on the holder area.

Thank you for a second time, Phil B. Being new to welding I was a.) Unfamiliar with the carbon arc torch and, b.) Looking for projects to utilize my burgeoning skill. Shortly after reading this page I found a dusty box of 3/32" gouging rods and have since played around with them as a two handed torch. (It feels a bit like dowsing for electric flame. Very exciting.) As of tonight my power cables are made, and the metal work is done. all that remains is to drill a few holes in some wood blocks and figure out where I'm going to find a suitable spring.

I will post the details once the deed is done, but I felt like expressing my joy as I transform discarded materials into a useful tool. (Welding fever has me wanting to make a box for my worm drive saw - something it needs. But a fancy borrowed TIG welder has exposed some problems in my plan, which this makeshift torch may yet solve! Those details should later follow in their own page.)

So, thanks again!

1 reply

Thank you. I wish you much success. 3/32" rods may burn away quite quickly. You may want a thicker rod for more heat.

Thanks for posting your instructable. I think I want to use your info as a starting point for a project I may build. I'm mulling over building a carbon arc lamp. If I had a way to feed the rods towards each other at the right rate, and had a 100% duty cycle welder, what's your best guess as to how long 12" rods would burn before they were consumed. I'm sure you've never sat and timed this, but any thoughts, musings, or feelings on the matter would be appreciated. Thanks.

6 replies

My rough guess would be 30 to 45 minutes. A lot would depend on how much current you run. More current would burn it up faster.

Motion picture projectors have often used carbon arc illumination, I wonder what those use for advancing the carbon rods.

In my youth I used to operate one them carbon arc projectors in a local cinema. It was wonderful watching the carbon rods burn away. You had to watch thru a special sort of welding glass and a small regulated motor (in series with a variable resistance for precise tweaking) kept the carbon rods just at the right distance apart. Sometimes something happened and off they went. Then the whole audience would start screaming their heads off esp at a suspense scene!! My instructor used to remind me to check the length of the rods before starting as once the show is on nothing can be done esp if they didn't last the whole reel.

I really miss those days when everything had to be done manually.

Thank you for your story. It sounds similar to my experience heating metal with carbon rods and an arc. But, I do not have a crowd angry at me if I lose the arc.

I'm not sure what they used to advance the rods back in the day of motion picture illumination, but here's a video of a more current attempt to create an arc lamp. One of the rods might be advanced by use of a stepper motor driving the frame that holds the rod:

https://www.youtube.com/watch?v=u8e_u_xqN30

Thank you for the video link. I notice the setup ran at about 23 amps. with carbon rods about 1/2 inch in diameter. Since the original title is in German, I expect the voltage is 230 volts. European systems run at 230 volts. I think the open (no load) voltage on an arc welder would be around 60 volts. I need to set the welder to around 70 amps. to get a decent carbon arc flame with 1/4 inch carbon rods. The larger carbon rods seem to have reduced the need for advancing the rods.

We used 1/4 inch carbon rods filled with a special composition to give more intense light. If I remember correctly power was about 60v at 90 amps or so which can be raised (for more light) but then they would consume quicker.

In step 7 I mentioned one wire is inserted into the ground clamp and the other is inserted into the electrode holder. Polarity is not important, but keep them from touching one another in use or there will be sparks all over.

can someone recommend what size of carbon rod and current for 220 ac welder.im planning to weld the floor pan for my Bug.thanks

4 replies

How are your planning to weld the floor pan in a VW Bug? Are you using carbon rods to make a hot flame that you use like an oxy-acetelyne torch to make filler metal fuse with the parent metal? Are you pressing carbon rods from both sides like a spot welder? Are you using a carbon arc flame to braze? Are you repairing something that tore? Are you making butt joints, or overlapping pieces of metal? Are you using a backing plate of copper or aluminum to minimize burning through?

Is #4 jumper cable alright to use

I am sure it would be fine.

I have 2 pieces of 3/8 rod 7 inch is that too heavy