# Twin Carbon Arc Torch



## Ulma Doctor

in high school, i learned oxy/acetylene welding and brazing operations.
when i went to community college in the late 80's, i spent 2 years and a semester learning welding processes.
gtaw and smaw. i learned a ton of stuff from a master welder who ran the program.
i would use a mig welder at work, get off work drive to school,show up early to class, and learned smaw on monday,wed
learned gtaw tuesday,thursdays. i couldn't get enough :welding:.
needless to say i got a lot of welding in and became addicted to joining metal together. 
i came across a process that's very old- carbon arc welding...
i have been intimate with a gouging torch may times, but never even considered carbon arc as a welding process.
come to find out that it was first discovered and used in 1800 and is effective on ferrous and non-ferrous metals.
 DCEN (straight polarity) is used. 
i then remember my welding teacher talking about brazing and welding with twin carbon arc on AC.
there was 1 half page explanation of the process in our textbook and i had forgotten all about it entirely.
i recently reread some of the textbooks and ran across some notes that i had taken on the subject.
the first thing that jumped out at me was the process was extremely effective for repairing cast iron, both as a welding process and a brazing process.:thinking:

i came to the sudden realization...
i never had the pleasure to twin carbon arc braze or weld anything:angry: this was a hurdle i had to jump, 
here's why...
i recently found a deal on a complete vintage 1972 wards(century) 230 ac welder w/ a twin carbon arc torch set up complete with some electrodes .
i have an old school JET 370 power hacksaw that has some cast iron in need of repairing...:biggrin:


the miter clamping bolt goes into a cast iron clamping plate with poor threading...


i got lucky on one side i was able to put a stud into the clamp on one of the clamps, an easy fix.
as for the other clamp, i wasn't so lucky.
 it was poorly drilled from the factory and not much of the thread profile remained.
 a stud was out of the question for now...
i thought to myself, what an excellent opportunity.... to try a new old thing
i fired up my recently acquired shop oven(on casters) and preheated my damaged clamp to 300*F


i took out the Twin Carbon Arc Rig, slapped a couple 3/8" carbon rods  cranked er' up to 90 amps and went to town on a brazing operation to fill up the hole in the cast iron. the process is slow , but, i was amazed that i didn't need flux on the brazing rod to get the puddle to stick. after a few minutes of brazing, BaddaBing ...

 i put the casting on firebricks inside the oven to cool overnight.
i'll post more as i finish the repairs!
stay tuned for part 2
thanks for reading!


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## November X-ray

You can also braze thin galvanized sheet metal together with Everdure (sp) rod and a single carbon without having the cyanide smoke release from the galvanizing.


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## Ulma Doctor

i Made the brazing repair on the miter clamp with the TCA and preped the clamp for the drilling operation!




i'll drill and tap the hole to accept a 1/2-13 stud to match the other clamp i repaired earlier.


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## Hawkeye

I can vaguely remember an article in Mechanix Illustrated (I think) in the '60s that told how to make a twin-carbon torch. As I recall, it plugged into a regular wall outlet and used an electric iron as a ballast to prevent the breaker from blowing.

Might have to make one to run off one of my welders. One more for the project list.


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## swarfed

thanks for the post Ulma Doctor.
 OMG, you sure stirred some old memories with this one.
(look at me, typing like a teenager)
i remember in the late 60s when my house payment was $98 a month.
 i splurged for a Lincoln 225 AC stick welder($104 out the door)
i found a can of 1/8" fleetweld 180 that had gotten wet, but it worked
 for crude cutting of old car frames and such.(one tuff little buzzbox)
but i needed a way to heat, bend and braze. a complete set of torches was
 selling for more than two house payments and i couldn't swing it.
Enter your "Miracle Tool"
 Montgomery wards carried an attachment for welders called a Carbon Arc Torch 
that claimed to do everything but clean your windows.
 it came with a variety pack of carbons and a hand held face shield for less than $30.
bakelite handles and a sliding thumb screw to adjust the arc.
 i used to light up the night skies at all hours. after a few visits from the cops and
the fire department, they told me if i was going to use that thing at night to close the door.
 my paranoid neighbors never knew what to expect to roll out of my garage.
they had a huge block party when i finally moved and let them have their peace and quiet.
   as they say.... the rest is history.
 But i finally got my torches, then plasma. i just counted 11 of the Red and the Blue welding devices.
that old carcon arc torch is probably still around here somewhere.
 thanks for shaking the cobb webs.
y'all remember what the old man said... always hammer on the cheapest part!


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## Ulma Doctor

Thanks swarfed , for giving my post a read!
i'm glad it stirred up them feelings)! here's the set up i got last Wednesday.







just as you described!

thanks ED for the input!!!


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## Ulma Doctor

After completing the TCA brazing repair, i prepared the clamp for the drilling operation.



i then tapped to 1/2-13 and cleaned the bore with laquer thinner and compressed air.
 i added high strength(red) locktite to the stud before installation.







a really fun fix, and used another process to boot:drinkingbeer:

thanks for reading, please add your comments and/or stories!


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## joconnor

Here is an old one I have in my collection of welding gear. The slider on top adjusts the carbon rods as they burn.


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## Ulma Doctor

here's another example of a brazing build up of a damaged lathe compound rest.
the part will be dressed down and filed to the correct dimensions.





the process is a little tricky to learn.
 the arc is very hot i've read somewhere in the neighborhood of 4,000*f and 9,000*f, dependent on amps,rod diameter, and i'm sure other factors not coming to mind.
the process is very simple and works equally effectively as an oxy/acetylene torch on brazing cast iron, albeit a little trickier due to the large volume of heat.
with more practice i'll take on other types of repairs, for now i'm concentrating on cast iron repairs.
thanks for viewing!


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## Bill C.

Thanks to all of you. I never used carbon welding but I am impressed with the results. I used to think carbon arc was used for creating light for search lights and big movie projectors.


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## Ulma Doctor

funny that you say that Bill
they are/were used for welding, brazing,spotlights and film projectors as other uses for the carbon arc energy!

thanks for you interest!)
i hoping to educate and have fun in the process!


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## British Steel

This thread sent me hunting out the instructions for my old Oxford arc welder, which has a tapping specifically for carbon rods - interesting bit was how to case-harden by rubbing the rod over low-carbon steels, fusing the carbon into the surface... I might have to try that!

Here in the UK arc brazing got a bad name because of adding carbon to car repairs, leaving the thin sheet hard and brittle, with bits dropping off, so it's now a test failure... Worth bearing in mind.

Dave H. (the other one)


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## owl

The late 1800's is sometimes referred to as the "Age of Blind Actors" due to the number that went blind performing in front of carbon arc lights.  The high UV tended to make cataracts.


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## Ulma Doctor

Here's a video of the repaired saw cutting some 2 1/8" Cast Iron
thanks for looking!






enjoy!


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## I.RonMann

I will have to dig out my "MAKIT YERSELF" booklets. ONE is how to make your own C.A. torch, (VEWY similar to the ward's) Another is a "DISINTIGRATOR" which uses a C.A. rod, drilled out, so it (get this) can pass WATER through. It feeds down, zapping broken taps, drill bits, and other hard to drill things that jam a hole. The water flushes out the zapped metal. I built one. IT WORKS! Then there is the benchtop C.A. furnace. It arcs metals into a puddle for casting small parts. The original instructions call for a "water resistor" which is an earthenware pot, filled with water, copper bars on opposite sides, series connecting your hot lead. Betw. line and load is an ammeter, and after plugging into a 110 receptacle, you add salt to the water until the meter reads 7 amps.:nuts: :thinking: :thumbsup: And they got us all thinking we need sophisticated equipment to put superhot to the metal... (There IS a good reason...)

that LAST one is a reprint from a boys project magazine, 1910-1930 somewhere...

- - - Updated - - -

NICE work BTW, :thumbsup:


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## DAN_IN_MN

Anyone know where I could get a few rods for a CA torch?  I picked one up at a garage sale a few years ago for $5.00.  Couldn't pass it up!:whistle::jester:


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## Ulma Doctor

Hi Dan,
i do have a source i was able to find that were reasonable in price:

How to order from Cinema Carbons - AC DC Carbon Arcs - color films


A word of caution if you are going to use AC power use AC Carbon Arc Rods, DC Rods will not function correctly on AC.
i found that out the hard way......
You can use the TCA in DC but you will need a large DC rod and a small DC rod, because the rods in DC do not get used up at the same rate.
For AC you can use the same size rods as they are consumed at the same rate.
i hope the info helps out!!
mike)


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## Terrywerm

Try your local welding shop, or even the welding area of some well stocked hardware stores. If you have trouble getting any, let me know, my local hardware store has them.


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## DAN_IN_MN

Ulma Doctor said:


> Hi Dan,
> i do have a source i was able to find that were reasonable in price:
> 
> How to order from Cinema Carbons - AC DC Carbon Arcs - color films
> 
> 
> A word of caution if you are going to use AC power use AC Carbon Arc Rods, DC Rods will not function correctly on AC.
> i found that out the hard way......
> You can use the TCA in DC but you will need a large DC rod and a small DC rod, because the rods in DC do not get used up at the same rate.
> For AC you can use the same size rods as they are consumed at the same rate.
> i hope the info helps out!!
> mike)



Mike

Thanks for the link, words of wisdom, and the PM!  Oh, that was my first PM on this forum!  You win!



terrywerm said:


> Try your local welding shop, or even the welding area of some well stocked hardware stores. If you have trouble getting any, let me know, my local hardware store has them.




Terry

I drove through your area today and I believe I saw "your hardware store".  LoL!  I thought that there is another hardware store I need to check out!


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## Billh50

reading about carbon arc torches brought back memories of my first arc welder. It was a Craftsman 110v. The ground clamp was also a holder for a carbon rod on the other end. you take the other rod holder and stick it into the insulated handle of the clamp. and then as you brought the 2 rods together it created a flame. wow was just thinking about how long ago that was.


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## Reeltor

The carbon arc torch brought back some memories.  As a kid, I took the carbons out of old D cell batteries and using a train transformer did some carbon arc.  No gloves, or eye protection :nuts:

The things we used to do while experimenting.

Mike


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## Silverbullet

My first one I bought out of the back of a mechanics illustrated. The carbons were mounted into two handles held on a flat strap of light spring steel. When you squeezed them together you got the arc. If ya let go they separated. Later years I had one for my craftsmen welder 235 with two ranges fully adjustable. I still have that welder and it works like it did forty years ago. The torch on that was my only torch for many years and it will blind YA if you don't use a shield.


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## markba633csi

The old number 6 dry cells had HUGE carbons in them that we'd make all kinds of carbon-y things with- ahh the good ol days- Coast to Coast hardware stores..and tube testers in the grocery store
Mark S.


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## Ulma Doctor

i remember coast to coast stores, and i do remember seeing a dusty tube tester at the old Hardware store in town.
i'd go back to that time in a second...


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