replacing the normal inert shielding gas with a flammable gas to increase heat output

[BB Rider]

In thinking about the contents of several recent threads, I came up with an idea to boost the temperature output of my MIG and TIG welders, which I am finding out don't have enough thermal output for what I am welding. Larger welders are financially out of the question for now. I want to try to replace the normal inert shielding gas with a flammable gas such as Acetylene, Hydrogen, Oxygen, or a blend of these. The flammable gas in conjunction with the welding arc should increase the heat output of my gun to where I need it to be in order to weld thicker materials. This simple idea combines the attributes of MIG/TIG with Oxygen/Acetylene/Hydrogen. Don't know why I hadn't heard of it before. Since the welding gun is actually a torch, it should be able to take the heat from doing this.
Have any of you tried this method? How did it work out?

[Steved]

I am not 100% sure if this can be done but thinking about it scares the crap out of me.

There are so many unknowns the first being that although the torch can probably take the heat it has not been designed as a combustion chamber capable of taking the pressures nor has it been designed to prevent flashbacks.

Additionally any combustion through gases would introduce carbon, hydrogen, water vapor and perhaps oxygen into the weld puddle resulting in a very poor weld.

I think that if anyone could answer this question it would be HAWK.

It sounds interesting I would like to find out the outcome of this thread.

My bet is that it cannot be done.

[klsm54]

I am not sure how to respond to this... .....It is definitely NOT a good idea. Safety wise, it is certain to inflict harm to the operator, and possibly the responding emergency personnel. Metalurgicaly, it is not feasable. The heat of an electric arc is many times hotter than any flammable gas flame, so there would be absolutely no advantage, if it could be done. My advice is to forget this notion, write it of as a bad idea and save yourself from serious injury. Also, if you cannot afford a larger welder, you certainly don't want to destroy the one you own now. Sorry to be so blunt, but if you are serious about this, I don't want to see you bring harm to yourself or others...

[Miller Kevin]

I will put this as simply as I can, DO NOT USE ANY FLAMABLE GAS AS A SHEILDING GAS! This would be extremely dangerous.

I recommend that you discuss your issues with your local distributor and see if they have any sheilding gas options that could help you.

Kevin

[email protected]

[cope]

Re: replacing the normal inert shielding gas with a flammable gas to increase heat output

Originally posted by BB Rider
In thinking about the contents of several recent threads, I came up with an idea to boost the temperature output of my MIG and TIG welders, which I am finding out don't have enough thermal output for what I am welding. Larger welders are financially out of the question for now. I want to try to replace the normal inert shielding gas with a flammable gas such as Acetylene, Hydrogen, Oxygen, or a blend of these. The flammable gas in conjunction with the welding arc should increase the heat output of my gun to where I need it to be in order to weld thicker materials. This simple idea combines the attributes of MIG/TIG with Oxygen/Acetylene/Hydrogen. Don't know why I hadn't heard of it before. Since the welding gun is actually a torch, it should be able to take the heat from doing this.
Have any of you tried this method? How did it work out?

Check the Darwin Awards site; if anyone has attempted this he is probably recognized there. Glad you asked before attepting this.

[GTA/SPEC]

Flammible gas is mixed into inerts for TIG welding only. And then its only Hydrogen, and in small percentages. Like 2% or 5%. It isnt consumed in the tig process like Oxy/Fuel is consumed in a flame. The Hydrogen is there to raise the ionizing voltage of the inert gas, forcing the TIG welder to produce more voltage to overcome the higher ionizing potential of the mix. The higher arc voltage is what increases the heat input, not the fact that its flammible. The use of argon-hydogen blends should only be used in a well ventalated area, and only used by professionals. The hydrogen will seperate from the argon after it is expelled from the torch and collect in the ceiling, creating a dangerous situation.

Higher concentrations of hydrogen in argon are used for heavy plasma cutting, 200 amps + . Usually a 65% argon 35% hydrogen in conjunction with a nitrogen backing gas. Same theory, the hydrogen is used to "up" the ionizing potential for a more potent and stable arc. Keep in mind 200 amps of plasma with a 200v arc is 4" long.

[JOHN1]

Is this a joke??

[fun4now]

oxygen bad

first off to put it simpelest the shielding gass is to keep oxygen out.
as for acetylen have you ever sparked off your O/A torch with the acet. too high not good and to try to mix the two gasses to creat a good flaime comming out of a mig ?????
i think klsm54 hit it on the head as for safty. i would not like to be youre neibor when you try this.call the fire department first.better yet try a different ideal and keep the place safe.
think safty first!!!!!

[Andy249]

Here in Aussie land we do run an Argon/Oxygen/Carbon Dioxide Mix. The Oxygen of course is in a very low quantity so it doesn't oxidise the material as you weld it. As far as I know it would be near impossible to add Acetylene into this mix as Acetylene in the cylinder is actually suspended in Acetone (I think!). The reasons behind this is that Acetylene is incredibly volatile particularly when compressed. This is the reason why Acetylene cylinders should never be transported / stored in any other position other than upright.

I don't think it would really be possible to add Acetylene for this mix, and for my way of thinking it would be bad idea! Gas companies are constantly researching to provide their customers with better gases to weld with, to be honest I would rather stick with the status quo. If you are having problems getting your material up to temperature, what about preheating? Sure it takes longer, but it would save you having to buy a bigger welder right now?

[Bulldog]

Hi bbrider,
If you decide not to take all this good advise and go ahead with your experiment.... One thought.... Video tape it!!!
Bulldog

[tackit]

Man I get serious when I put butane in my little torch, the way it spurts out when it's full causes me to be extremely careful. This idea is so far out I couldn't imagine anyone seriously trying to do it.


Bon voyage brother, after the explosion I will be looking for you when you fly past the moon.

[fun4now]

preheat

looks like we all overlooked the obveus preheat would get you better penitretion
good thought andy249

[HAWK]

BB rider,

Welcome aboard.

There are several posts on this board regarding the use of argon and hydrogen shielding gases. AS GTA/SPEC stated these mixtures are only for the TIG process and for use by trained professionals! Please do not attempt any such antics as you have described.

If you will explain your specific problems we will all be glad to pitch in and help you get the job accomplished in a safe manner. Again welcome and we are glad you asked before doing.

[BB Rider]

I spoke with my welding supply and gas distributor this morning and he said that the only thing that I would accomplish by shielding with flammable gas was the possibility of leveling the neighborhood and blowing my A$$ to Kingdom Come. I read up on gas chemistry and was reminded that hydrogen and oxygen are what rockets are fueled with and that pure acetylene may be very unstable. The "friend" who gave me the idea to use of flammable gas even offered to fabricate the gas plumbing to send acetylene and oxygen through my mig and tig. What a friend. Thanks to all for suggesting I NOT do this. I think my problem is actually that I don't have nearly enough machine to weld what I've been encountering lately. I have been finding myself trying to weld 1/2" to 1" mild steel plate, 1"-2" solid steel bar, and 1/2" aluminum with a MillerMatic 175 and/or an EconoTIG. I originally bought the welders to weld hollow steel bar and channel and thin aluminum plate. If there's no way this can work, please tell me. How does one preheat a weld? If I do need to bite the bullet and buy a larger machine, is there one which is capable of both processes? I weld for a hobby and to work on personal projects, not for financial gain.

[BCarlucci]

There are ways around this problem including preheating the work piece, the other shielding gas mixes could help, but everyone is right these should only be used by professionals. Just as an example an old customer of ours tried to do some "mixing" on his own and his shop is no more, now this was about 10 years ago, but still the guys i lucky he's alive, he leveled his almost 3,000 sq ft shop. has a new one over it now, but still you get my drift. No idea is a dumb idea, we just don't think you should try it.

BC