Carbon arc torch, anyone used one?

[arse_sidewards]

I'm thinking of building one. There's several guides online but they're all kind of jank so I'll probably build something a little more substantial but basically the same. Anything I need to know or pitfalls I should be aware of?

The reason behind this is that I have a plasma cutter that already covers my cutting needs better than an oxy-fuel torch and I don't want to have drag cylinders around to preheat shit when I have enough welders I could station them wherever I need them. The main use for this will be pre-heating cast iron and thick aluminum. Edit: Also brazing

 

[Pitbullcruiser]

I have used one for gouging, scarfing and removing welds, they are awesome. Never heard of preheating with one.

 

[Ugly pumpkin]

I have used one for gouging, scarfing and removing welds, they are awesome. Never heard of preheating with one.

Same here.
Used one for knocking out axle tube plug welds once. Looking back, don't remember why I didn't use oxy acetylene.

Edit. I'm an idiot. Disregard my comment.

 

[Benny]

I have used one for gouging, scarfing and removing welds, they are awesome. Never heard of preheating with one.

That sounds like air-arc. Different process.

 

[arse_sidewards]

I'm talking about one of these.

not one of these

 

[ExWrench]

The main use for this will be pre-heating cast iron and thick aluminum. Edit: Also brazing

These aren't the droids you're looking for.

Carbon arc is great for gouging, scarfing, etc. but the extreme localized heat that's great for cutting is horrible for preheating. You'll overcook the fuck out of the contact area and probably liquefy it (adding sacrificial carbon and changing your metallurgy) by the time you get heat into the meat of the metal.

You'd be better off misusing a TIG torch - at least you wouldn't be pumping carbon into the locally overheated area.


EDIT:

I'm talking about one of these.






not one of these

OK, I thought you were referring to a carbon arc gouging setup. I have no experience with that other hooptybidness

 

[Muckin_Slusher]

For preheating, couldn't you just swap out your arc welder rod holder for a second ground, clamp both "grounds" on the chunk you want to heat and turn on the welder? Pretty sure that is the process town workers use to thaw frozing pipes in the ground.

 

[arse_sidewards]

For preheating, couldn't you just swap out your arc welder rod holder for a second ground, clamp both "grounds" on the chunk you want to heat and turn on the welder? Pretty sure that is the process town workers use to thaw frozing pipes in the ground.

For small parts I could. Big parts would need so much amperage I'd fry the welder, preheat the welding leads or liquefy the bits of ground clamp that touch the part) long before it preheats the part. I don't think I could even preheat aluminum at all using that method. Air has pretty decent resistance so I'll need way less amps to preheat by arcing through the air than to preheat through the part.

 

[Muckin_Slusher]

For small parts I could. Big parts would need so much amperage I'd fry the welder, preheat the welding leads or liquefy the bits of ground clamp that touch the part) long before it preheats the part. I don't think I could even preheat aluminum at all using that method. Air has pretty decent resistance so I'll need way less amps to preheat by arcing through the air than to preheat through the part.

Well, ok.

I'm not really a welder, I'm just an electrician, but doesn't that thing you pictured use a welder as a power source?

If so and a watt is a watt then I don't get the difference.

If you're using a stick welder then you can simply turn down the amperage (constant current machine) to a level that your machine and leads can withstand.

Note: I'm only asking questions to understand. I realize I'm likely confused, as usual.

 

[sdmuleman]

I don't see how that setup would do anything useful for thick metal - arc from electrode to electrode means the only heat going into the material is what you get from radiation, which in the grand scheme of things wouldn't be all that much. I can see if being useful for 1/4" thick or so, but much beyond that I don't think you're going to economically accomplish much. Probably be better to use some sort of resistance heating setup, probably with lower amperage but over a longer time. Not sure how hot you need to get, but that was how stuff was done in the shipyard I was at - resistance heat and thermal blankets.

Air arc on the other hand is a very useful toy to have.

 

[ThePanzerFuhrer]

Air arc on the other hand is a very useful toy to have.

Fuck air arcs, the rare time I need to cut something huge I bust out the oxylance. These bad boys are the real deal.

 

[sdmuleman]

Fuck air arcs, the rare time I need to cut something huge I bust out the oxylance. These bad boys are the real deal.

WTF is that thing???

I don't use air arc for cutting much, but it's awesome for gouging for stuff like removing welds. I've used it quite a lot for fillet welds for things like fork hooks on loader buckets and removing a welded on bed from a truck frame. Done right, air arc lets you easily gouge out the weld without cutting much of the base metal away so you can easily reuse parts. No way to do that with a torch or plasma. Could do the same with a grinder, but far easier with air arc.

 

[ThePanzerFuhrer]

WTF is that thing???

I don't use air arc for cutting much, but it's awesome for gouging for stuff like removing welds. I've used it quite a lot for fillet welds for things like fork hooks on loader buckets and removing a welded on bed from a truck frame. Done right, air arc lets you easily gouge out the weld without cutting much of the base metal away so you can easily reuse parts. No way to do that with a torch or plasma. Could do the same with a grinder, but far easier with air arc.

lol it’s a rod of thermite. you hook a oxygen bottle up to it and you can burn a hole through a 15” thick plate. Awesome for punching holes in pins that are stuck in a bore.

https://m.youtube.com/watch?v=rSpXJJ-ris8

 

[sdmuleman]

lol it’s a rod of thermite. you hook a oxygen bottle up to it and you can burn a hole through a 15” thick plate. Awesome for punching holes in pins that are stuck in a bore.

https://m.youtube.com/watch?v=rSpXJJ-ris8

Ahh, didn't recognize it from the picture. Looked like you were holding a punch or something.

 

[[486]]

my grandpa used the shit outta one, but he's been dead a while now. :\
had a whole pile of ancient flashlight batteries that he'd dig the carbons out of to use

like with everything, no doubt you'll figure it out if you set your mind to figuring the shit out. More likely you'll get frustrated and find out why everyone drags around a fuckin' torch set.

 

[projectdad]

Have any of you guys ever used a petrogen type cutting torch, it uses oxygen and a compressed tank of gasoline instead of acetylene.
https://youtu.be/zC_5_TYWhbA

 

[[486]]

Have any of you guys ever used a petrogen type cutting torch, it uses oxygen and a compressed tank of gasoline instead of acetylene.
https://youtu.be/zC_5_TYWhbA

just use oxy-propane
seen that a long time ago, looks neat but expensive

 

[tracyb]

i have been self employed welder/ fabricator for 5 years now and how only broke out the carbon arc/ air arc once. and only for a job that required it. i also dont own a bottle of acetylene.

99% of cutting and gouging is done by plasma a hypertherm 65. i ocassionally use oxy-pane. mostly with rose bud for removing bolts and such. for preheating to weld only a propane weed burner.


before goingout on my own i worked at a shipyard and we used carbon arc allot to back gouge for full pen welds. and the yard was transitioning to plasma, but because people are dumb you had to pass the ' not a tard' test to use plasma. so its a slow transition.



if you dont have a specific need for carbon arc i would not try it.


edit just saw the pics. not the torch i was thinking.... not somthing i would plan to waste my time with. i do however occasionally sharpen a carbon rod and use it low amperage to braze galv sheet metal with silbronze. use it in a similar action to sctrach tig.

 

[jpmassey]

Use a oxylance. It's a super fun toy. Just make sure you have it spaced way off the concrete floor!

 

[projectdad]

;n118107]
just use oxy-propane
seen that a long time ago, looks neat but expensive

Yep oxy-propane is my go to.
I'd stumbled onto the Petrogen oxy-fuel torches some time back and thought that considering how expensive they are for my needs there wasn't any advantage, and I've never talked to anyone that's ever used an oxy-fuel setup so it must not offer any real advantages or I'd suspect it would be a bit more common.

 

[arse_sidewards]

We're how fucking deep in this thread now and half of you idiots still think we're talking about carbon arc gouging and cutting operations?

;n117896]my grandpa used the shit outta one, but he's been dead a while now. :\
had a whole pile of ancient flashlight batteries that he'd dig the carbons out of to use

like with everything, no doubt you'll figure it out if you set your mind to figuring the shit out. More likely you'll get frustrated and find out why everyone drags around a fuckin' torch set.

Yeah, I think that's how this is gonna go. I already know why people use torches, because you already have a torch around for cutting so why not preheat with it too.

If so and a watt is a watt then I don't get the difference.

If you're using a stick welder then you can simply turn down the amperage (constant current machine) to a level that your machine and leads can withstand.

Which is gonna make more heat? 200A through copper and steel or 200A through something with some serious resistance? Sure I could just heat the part with sheer amperage but that's far less efficient, likely to the point of ineffectiveness.

 

[Chevy_man]

We're how fucking deep in this thread now and half of you idiots still think we're talking about carbon arc gouging and cutting operations?



Yeah, I think that's how this is gonna go. I already know why people use torches, because you already have a torch around for cutting so why not preheat with it too.




Which is gonna make more heat? 200A through copper and steel or 200A through something with some serious resistance? Sure I could just heat the part with sheer amperage but that's far less efficient, likely to the point of ineffectiveness.

Uhhh... 200A is 200A. It can't make any more or less heat.

Are you doing the usual "I'll make it work to spite you" and refusing to learn from others?

 

[ironman_gq]

Uhhh... 200A is 200A. It can't make any more or less heat.

Are you doing the usual "I'll make it work to spite you" and refusing to learn from others?

200A is not 200A, all depends on the voltage. Arc welders are constant current power supplies, they'll make 200 amps but the voltage varies so heat output varies depending on arc length. What I think you meant to say is "Watts are Watts" which would be the heat output or actual energy provided.

 

[Muckin_Slusher]

We're how fucking deep in this thread now and half of you idiots still think we're talking about carbon arc gouging and cutting operations?



Yeah, I think that's how this is gonna go. I already know why people use torches, because you already have a torch around for cutting so why not preheat with it too.




Which is gonna make more heat? 200A through copper and steel or 200A through something with some serious resistance? Sure I could just heat the part with sheer amperage but that's far less efficient, likely to the point of ineffectiveness.

So, what's your plan then with that arc-y thing? I'm assuming it will arc from one electrode to the other through the air? How far apart can you get the electrodes once the arc is initiated?

Are you just gonna hold the arc close to the thing you want to heat up?


Oh, and get the fuck out of our cutting thread. I wanna see more of panzer's light saber.

 

[Chevy_man]

200A is not 200A, all depends on the voltage. Arc welders are constant current power supplies, they'll make 200 amps but the voltage varies so heat output varies depending on arc length. What I think you meant to say is "Watts are Watts" which would be the heat output or actual energy provided.

It's all relative. I assumed he was powering his contraption with a constant current arc welder.

 

[[486]]

It's all relative. I assumed he was powering his contraption with a constant current arc welder.

which the voltage varies on quite wildly, generally something like 21v while welding, mine sits around 90v open circuit, and if you strip off a foot of your 4/0 leads and wrap them around the foot of 4" round stock you want to heat up there's probably about 2v of drop across the leads and part. I'd bet on a 200' run of buried and frozen 3/4" copper tubing having a good bit more resistance than a foot of steel

for the math bit:
21v times 200a is 4200 watts
2v times 200a is 400 watts (but the welder will be very sad about what you're choosing to do to it)

 

[arse_sidewards]

I found an old Lincoln carbon arc torch on eBay. So far I've just used it to bend exhaust hangers. Takes some getting used to but it works great.

 

[billdacat]

I found an old Lincoln carbon arc torch on eBay. So far I've just used it to bend exhaust hangers. Takes some getting used to but it works great.

I am new to TIG... But I find TIG is great for heating up shit that I want to bend. I have done some Heliarc off an old Idealarc 250 (man do I miss that bitch).

 

[arse_sidewards]

I am new to TIG... But I find TIG is great for heating up shit that I want to bend. I have done some Heliarc off an old Idealarc 250 (man do I miss that bitch).

Now imagine how much better it would be if you didn't have to make the arc hit the part. That's a carbon arc torch.

 

[Muckin_Slusher]

Now imagine how much better it would be if you didn't have to make the arc hit the part. That's a carbon arc torch.

So, since you didn't respond to post #24, I'll ask again.

Are you just holding the arc close to your part and not actually passing current through the part? What makes that a great way to preheat stuff and why isn't everyone else doing it?