Carbon arc gouging

[Memmeddu]

Jim in your opinion what’s a good inverter three phase for gouging?

Does gouging really muck up engine driven machines say a Vantage 400 or Miller Big Blue?

People say they don’t weld right if you gouge off them too much.

Brad I think I need apologize about Esab and siderotermica , I found that I was wrong hope you can understand.
Sorry about that .
Have you any tips about gouging that you can share with me ?

Ps sorry again I'm young and I have many things to learn yet about anything

 

[Jim Davey]

Jim in your opinion what’s a good inverter three phase for gouging?

Does gouging really muck up engine driven machines say a Vantage 400 or Miller Big Blue?

People say they don’t weld right if you gouge off them too much.

And they are right. In the refinery near me they use 500 and 700 amp engine drives.
I have Miller XMT 456 CC/CV 600 amp units for gouging but I won’t put them out for more than an 8mm carbon (they can do more but I’d rather not stress them) but since I have two I can run them in tandem to make a 1,200 amp power source for running 10 and 12mm carbons if necessary.

However you can gouge off just about anything as long as you are sensible with the carbon sizes.

So your set will in theory do a 1/4”-6mm Carbon but that’s pushing it. I’d go the next size down unless it was really for a short amount of time.

 

[Memmeddu]

And they are right. In the refinery near me they use 500 and 700 amp engine drives.
I have Miller XMT 456 CC/CV 600 amp units for gouging but I won’t put them out for more than an 8mm carbon (they can do more but I’d rather not stress them) but since I have two I can run them in tandem to make a 1,200 amp power source for running 10 and 12mm carbons if necessary.

However you can gouge off just about anything as long as you are sensible with the carbon sizes.

View attachment 190673

According with this charts I could use my 250A for gouging if I need using 3,2mm carbon rods
I think that can be the only rod I can run with my welder ...
This open me a new page of my learning path
So after getting the plasma cutter and a mig welder
I will take a cheap inverter welder (no regrets if I kill it ) an arc air clone torch ( I can't afford the original) .
Probably they will take dust on the shelf but I will have something to practicing with when I need
Can be a good rig for hobbyist application (a gouging every 3 years I believe)

 

[Jim Davey]

According with this charts I could use my 250A for gouging if I need using 3,2mm carbon rods
I think that can be the only rod I can run with my welder ...
This open me a new page of my learning path
So after getting the plasma cutter and a mig welder
I will take a cheap inverter welder (no regrets if I kill it ) an arc air clone torch ( I can't afford the original) .
Probably they will take dust on the shelf but I will have something to practicing with when I need
Can be a good rig for hobbyist application (a gouging every 3 years I believe)

I really can’t see you having much need of it but learning even if it’s learning for the sake of it is a noble calling.

 

[Memmeddu]

I really can’t see you having much need of it but learning even if it’s learning for the sake of it is a noble calling.

Generally I ain't even need to use my 7 inches angle grinder
Generally helmet, gloves ,chipping hammer ,welder and my 5" metabo is almost all that I need
But sometimes I do need a plasma cutter (which I will buy soon) ,an oxyfuel rig (for the moment I can use a blow torch), but when I had to grind to beveling cracks and repair fillets welds for something like 6 hours using an 9" grinder ,I that moment I wished to have something to gouging
This is only a case but yes I would like to learn how to use an arc air also if I don't need every day .
There are many things related to metal fabrication world that I would like to know and learn
But I would like to avoid to turn my hobby into a full time job , essentially because I like it and this makes me happy
I'm sure that if I will do this for work ,stress and related things about work will make me hate metal fabrication

 

[pedrobedro]

I used to work in a fettling bay on a 1200 amp arcair machine. I did it for a couple of years and it's hot, dirty and noisy. We were levelling off castings after the heads had been burnt off with oxy propane. There's no real skill to it you just need to know when to stop. They had to keep a few spare diodes in stock as it was prone to burning them out when used flat out for a good few hours. The diodes were the size of a D cell battery.

 

[Memmeddu]

I used to work in a fettling bay on a 1200 amp arcair machine. I did it for a couple of years and it's hot, dirty and noisy. We were levelling off castings after the heads had been burnt off with oxy propane. There's no real skill to it you just need to know when to stop. They had to keep a few spare diodes in stock as it was prone to burning them out when used flat out for a good few hours. The diodes were the size of a D cell battery.

Diode wise I will do something to protect them , essentially I will use 1/10 of what you use so on a 400A rathed inverter welder it could works
Otherwise there is also the fact that the welder is selling for 400A but maybe is way Lower ,I will do research about

 

[pedrobedro]

The copper coated carbon rods we used were 25mm thick and you had to wipe from right to left to blow the dross away running 150psi air pressure. Sometimes the copper torch air jets melted as well and I kept a bucket of water for when the hot metal went into my boot, just stick your foot in and take your boot off after. Man I got through some socks on that job and some of the burns took months to heal.

 

[brightspark]

The copper coated carbon rods we used were 25mm thick and you had to wipe from right to left to blow the dross away running 150psi air pressure. Sometimes the copper torch air jets melted as well and I kept a bucket of water for when the hot metal went into my boot, just stick your foot in and take your boot off after. Man I got through some socks on that job and some of the burns took months to heal.

shoulda worn foundry boots then

 

[Richard.]

The copper coated carbon rods we used were 25mm thick and you had to wipe from right to left to blow the dross away running 150psi air pressure. Sometimes the copper torch air jets melted as well and I kept a bucket of water for when the hot metal went into my boot, just stick your foot in and take your boot off after. Man I got through some socks on that job and some of the burns took months to heal.

Wow 1 inch carbons!!!
I bet they went with a bang when juiced up.

 

[anto44]

I've never done carbon arc gouging before but I've watched a guy who does repairs to heavy machinery doing it, it's an awesome process but unless you have a particular application for it I don't think it'd be worth the investment. For someone just doing DIY metalworking a plasma would probably be a better place to invest your money.
I've done some gouging with my stahlwerk cut 50 a few times, nothing heavy duty just removing small brackets from trailers that sort of thing and it worked fine, not as good as a proper carbon arc setup but good enough for the odd time I need to do it.
What kind of applications do you want to use arc gouging for? There doesn't seem to be many people on here who do it outside of a business so I'm sure people on here would be able to suggest ways of doing things using more common tools.

 

[Memmeddu]

I've never done carbon arc gouging before but I've watched a guy who does repairs to heavy machinery doing it, it's an awesome process but unless you have a particular application for it I don't think it'd be worth the investment. For someone just doing DIY metalworking a plasma would probably be a better place to invest your money.
I've done some gouging with my stahlwerk cut 50 a few times, nothing heavy duty just removing small brackets from trailers that sort of thing and it worked fine, not as good as a proper carbon arc setup but good enough for the odd time I need to do it.
What kind of applications do you want to use arc gouging for? There doesn't seem to be many people on here who do it outside of a business so I'm sure people on here would be able to suggest ways of doing things using more common tools.

A cut 50 is the first on the list because I need a plasma cutter ,not every day but on almost 40% of my past projects it can be handy , and also because is cool
Arc air not original products ,23 euros for the bare torch without lead ,a dirty cheap welder and 20 euros of rods
I would like to have one in the future essentially to learn how to use it
Once I get the plasma cutter there are few possibilities to need an arc air but tight spots is one of these

About your plasma how do use it to gouge?
Did you modify a nozzle ?

 

[pedrobedro]

shoulda worn foundry boots then

We had foundry boots and thermal suits and gloves and still got burns in unexpected places. Gloves were silver backed and leather fronts and lasted two days before they were too stiff to grip with. Wiping metal away was like spreading butter it was so powerful.

 

[anto44]

About your plasma how do use it to gouge?
Did you modify a nozzle ?

Basically just hold the torch at as much of an angle as you can and adjust the power until it's cutting in just the right amount. There are proper gouging consumables available but I haven't tried them yet, I modified a standard tip to try and get the same results as the modified tips. It worked better than using the standard tip but I can't compare it to a proper gouging tip.

 

[Memmeddu]

Basically just hold the torch at as much of an angle as you can and adjust the power until it's cutting in just the right amount. There are proper gouging consumables available but I haven't tried them yet, I modified a standard tip to try and get the same results as the modified tips. It worked better than using the standard tip but I can't compare it to a proper gouging tip.

Also air pressure is something important
Did use a lower pressure than cutting?

 

[anto44]

Also air pressure is something important
Did use a lower pressure than cutting?

No I kept the air pressure the same as for cutting, I did try lowering the pressure but didn't find it helped. I'll get some pics of the way I modified the tip tomorrow evening, I basically ground a flat onto it so I could hold the torch down closer to the material while holding the torch at about a 30° angle so it would scoop material out rather than just blasting through it

 

[Memmeddu]

No I kept the air pressure the same as for cutting, I did try lowering the pressure but didn't find it helped. I'll get some pics of the way I modified the tip tomorrow evening, I basically ground a flat onto it so I could hold the torch down closer to the material while holding the torch at about a 30° angle so it would scoop material out rather than just blasting through it

If possible I would like to see how the groove appears .
What about your set up?
SG/AG or PT31 Torch ?

 

[Munkul]

I've used my 40 amp plasma for gouging out cracks on a bucket edge with a standard HF torch. I found the best way was to adjust angle and amps until i could slice a bevel right off... i.e. a bevel Vee cut each side of the crack. Quick dressing with grinder, and ready to weld up.

It's horrible really, makes a real mess, but physically easier than grinding a decent 12mm groove out

One of these days i'm going to buy an arcair torch to try 3/16" carbons with my XMT304, more for the interest of seeing what it's like than actually any real commerical need.

 

[Memmeddu]

I've used my 40 amp plasma for gouging out cracks on a bucket edge with a standard HF torch. I found the best way was to adjust angle and amps until i could slice a bevel right off... i.e. a bevel Vee cut each side of the crack. Quick dressing with grinder, and ready to weld up.

It's horrible really, makes a real mess, but physically easier than grinding a decent 12mm groove out

One of these days i'm going to buy an arcair torch to try 3/16" carbons with my XMT304, more for the interest of seeing what it's like than actually any real commerical need.

Something like me I would like to get an arc air in the future more for interest than a real need
If you go on AliExpress and you search arc air torch you will find cheap bare torches for something like 22€ less than 20£ I believe
You take 2 meters air hose and you wrap it using 6mm or even 4 mm copper cables (sections or 2,5meter long ) heat shrink tubing or insulation tape a ring terminals where to clamp your electrode holder
An oil bottle as insulation boot
This to avoid import taxes
There are even complete torches for something like 35 euros but I don't know how they may cost adding taxes
Someone said that you could tap the holes on the torch and put in drilled through screws to reduce the air flow increasing the pressure

 

[Memmeddu]

Also if this could happen in the future I want share an idea that I thought during this topic
So is better avoid inverter welders to do carbon arc gouging
The other two options are
A big engine driven welder
A big transformer based stick welder

Now to allow someone like me (hobbyist) to use an arc air rig the only valid option is a buzz box , but we know that this machines are for the majority AC
So you have to convert it to DC

Why I will not buy a DC transformer welder , essentially because they are big machines and they are expensive , and also because I have only single phase

So to an hobbyist that would like to have a small arc air set up I think that is the only way to go
1 get a 250 or 200A buzz box
2 get some heatsinks
3 get or build a 400A rectifier bridge
4 get or build an inductor
5 get 2 fans
So essentially the idea is that you have to do something to increase the duty cycle first
I believe that if you put 3 heatsinks one on each side of the transformer you increase the heat transfer between air and transformer itself
Next step is to upgrade the fan ventilation , using a bigger fan that takes the air from the inside of the welder to the outside .
Pull works better than push , because if you push air on a surface part of this will flow back to the source , pulling allows the air to flow from the front to the back of the machine without losing to much flow .
Now the conversion itself
I don't know if is a necessity but on my genset , there is an high current winding that use chokes before the rectifier so...
I believe that it could possible put two small chokes before the 400A rectifier .
The rectifier needs to be mounted on a heatsink.
Out put a big inductor on to the positive cable , some X μF AC 450V capacitor or DC capacitors (AC are cheaper and they should be stronger against short circuit) , some sort of resistor to discharge the capacitors

Now the "converter" needs an housing to put the components in this order
Fan - inductor - rectifier bridge - capacitor battery
Why ?
Because the fan is taking the air from the inside out , so the fresh air flows from the opposite side of the fan to the fan itself .
The first thing we want to cool is the capacitor battery , because they can't stay warm
The second is the rectifier because also him can't stay warm but it has an heatsink
About the choke I have no idea if can stay warm or not but on my genset they are next to the exhaust manifold so...

A carbon arc torch from China , some carbon rods (3,2mm) and you are on business


Talking about money ,the only thing you are obligated to buy is the rectifier bridge ,the torch and the rods .
All the other components can be got for cheap or even free from a scrapyard

That's an idea , I don't think you will take me seriously anymore after posting that , but if you are interested I could make a thread with drawings about assembly and wiring diagram
And PROBABLY in the future some pictures about if I will make this conversion