Gas Welding Joints & Beads

[cwilliamrose]

I can understand the lack of bright shiny metal on a farm.

I did not know that that type of aircraft welding required oxyacetylene, but I can definitely understand why that would be the case.

I am with ya on the arc welding for heavy plate!

Most aircraft 4130 welding is done with TIG these days. I used to gas weld 4130 but TIG spoils you. Some factory aircraft welding is done with MIG but that's not the norm. And most aircraft tubing is very thin compared to what you see being welded in this thread.

 

[mattthemuppet2]

Erik, I forgot to ask, did any of those tips for your torches?

 

[erikmannie]

Erik, I forgot to ask, did any of those tips [work] for your torches?

Yes, 2 of the tips that you sent fit torches that I have.

 

[mattthemuppet2]

super cool! The ones that didn't fit will be a good excuse to buy torches to fit them

 

[erikmannie]

Here is the first bead from today, another flat T-joint:



The only problems are that it is not pretty, there is some undercut, & there is cold lap on each end.

I used a different O/A cart (and a medium rather than a large torch) for this so all of the equipment is different than what was giving me the jet force.

I had no jet force, but I think this is because I bumped up to a #3 tip. Gas welding goes a lot better when you have enough heat. It is quite miserable when you don’t have enough BTUs.

 

[paradox_pete]

Most aircraft 4130 welding is done with TIG these days. I used to gas weld 4130 but TIG spoils you. Some factory aircraft welding is done with MIG but that's not the norm. And most aircraft tubing is very thin compared to what you see being welded in this thread.

This is my understanding. Would be surprised if there are any production aircraft being gas welded. I'm an aircraft mechanic by trade, and have patched up a few old rag and tube aircraft in the past. Typical tube would be around 3/4" OD and .049 wall. It varies a little of course, and does get a little larger and thicker in the landing gear area, but is generally surprisingly light.

It is amazing what can be gas welded with the right flux. I have personally gas welded aluminum, though I found it quite difficult, as the metal gives little indication it has melted. I'm pretty sure stainless, inconel, and other exotic materials were gas welded back in the day.

 

[erikmannie]

This is my understanding. Would be surprised if there are any production aircraft being gas welded. I'm an aircraft mechanic by trade, and have patched up a few old rag and tube aircraft in the past. Typical tube would be around 3/4" OD and .049 wall. It varies a little of course, and does get a little larger and thicker in the landing gear area, but is generally surprisingly light.

It is amazing what can be gas welded with the right flux. I have personally gas welded aluminum, though I found it quite difficult, as the metal gives little indication it has melted. I'm pretty sure stainless, inconel, and other exotic materials were gas welded back in the day.

I am interested to get some flux for gas welding on aluminum, & I will be trying that soon in this thread. So far I have only found these offerings for an appropriate flux:

Forney Alum-a-Flux Jar 4 oz.

Helps keep oxides from forming during welding and is a cleaning agent for the molten rod. 1/4 Lbs. (7.09g).

www.littlehardware.com

and

Aluminum Welding Flux

TM Technologies: Tools, Sheet Metal Shaping Machines, Gas Welding Supplies, Articles & lWorkshops for Better Metalworking

www.tinmantech.com

I failed to link to eBay, but here is a screenshot:



Regarding not seeing the puddle in aluminum while gas welding, isn’t this the same as not seeing the puddle in aluminum while TIG welding?

By the way, this is why I prefer TIG welding on steel rather than on aluminum because of not being able to see the keyhole. I only choose aluminum when steel will not suit the application.

Honestly, I find steel to be very user friendly, but I have yet to warm up to aluminum as a material for welding.

We are lucky to have TIG as an option for welding aluminum, as the aluminum stick welding electrodes are a challenge (although once the base material is warmed up they will function).

 

[cwilliamrose]

Regarding not seeing the puddle in aluminum while gas welding, isn’t this the same as not seeing the puddle in aluminum while TIG welding?

There is a glare from the flux that makes seeing the puddle very difficult. Kent White sells some blue goggles for gas welding aluminum that everyone seems to like. I like his flux, which you linked above, and have used it (very sparingly) while TIG welding AL to shield the back side of the weld. That technique has some other benefits too but there's that same glare to deal with. Haven't tried gas welding AL yet since I don't have good goggles.

 

[cwilliamrose]

Here's a bit of screwing around I did to see what I could get away with using the Tinman's Premium Flux with TIG. I found the puddle stayed together even when it got stupidly large. Without flux it would have hit the floor at less than half the size. And the back side of the weld knitted together very well.

The upper image is the torch side of the weld, the bottom image is the back side. There are two welds here both heading toward the center of the panel. The first one (on the left) got really wide and started to sink, the second one got even wider as I really leaned on the pedal and the puddle only collapsed when I got close to the end of the first bead (something I've seen happen near tacks as well but I don't understand why).



If you guys play with this at home, use a very thin coat of flux on the back side only -- so thin as to be almost invisible......

 

[Charles scozzari]

Most aircraft 4130 welding is done with TIG these days. I used to gas weld 4130 but TIG spoils you. Some factory aircraft welding is done with MIG but that's not the norm. And most aircraft tubing is very thin compared to what you see being welded in this thread.

I know there is wire to use with a mig for 4130 and am wondering if anyone has used it. I also remember hearing a story of race car chassis that was mig welded and was then annealed in a large oven. I'm not to sure of that one, but who knows.