Tig welding 4130 tubes, neeb question

[kakarot]

Awesome, thnx for tips, I will run then 20 to 25cfh.
I go try to buy the gas tank today, getting a biggest one, getting 244cf of argon. at about 25 cfh it should give about 10hrs of work, is that true or it uses a lot more. Will try to get the filler rods if the store has them, otherwise I order online. The accessory kit that came with the welder had yellow/gold tungsten. ether a thoriated at 1% and radioactive or lathaneded at 1.5%. I might just buy some premium tungsten. I also have a gray one, and a red one but they are 1/8.

I might get the gas lens, To waste less gas if its a non expensive thing. If its over 30 buks, then probably I wont get it.

I will also get couple of tig gloves, a welder sleves, my friend wants a mask, umm thats preaty much it then. Oh and the part where the tungsteen goes back into the handle, it got broken, so I need it so I wont waste any tungsteen.

I am kinda on a budget.

As soon as I will do anything I will post some pics. maybe couple of practice welds, and frame is starting to build up.

[phila.renewal]

Whatever it's worth, I've read that ER70S-2 is recommended for welding 4130.

Save the -6 for mild steel.

Good luck with it.

[kakarot]

Thank you all for responses, will go to the store tomorrow, today closed.

[kakarot]

Got 300cf of argon, ordered er70s2 welding rods, will pick up on wed.

Soon some pics........

[fun4now]

cool, looking forward to the pic's.

[gary gonzales]

hello all,
preheating or annealing as some call it,it not required on 4130 tubing
you would have to get the tubing a 1550 degrees,and hold it a that temp
from anywhere to 30min to 24hrs ,depending on the thickness,and as far
as what cup to use i use a no.8 for all my tubing,and if you want it to look
really slick,,,use a gas lense cup

[Aerometalworker]

hello all,
preheating or annealing as some call it,it not required on 4130 tubing
you would have to get the tubing a 1550 degrees,and hold it a that temp
from anywhere to 30min to 24hrs ,depending on the thickness,and as far
as what cup to use i use a no.8 for all my tubing,and if you want it to look
really slick,,,use a gas lense cup

Gary,
Preheating is different then a post weld anneal. And yes you need the post weld anneal to do a proper job. Im not going to go into the details of it here but the short version is the untempered Martensite due to the rapid gas quench when tig or mig welding the thin material. Simply warming the joint up to a dull red, and slowly letting it cool takes the Martensite through its critical temperature range without it becoming un-tempered. You wont find this on think sections but its very common on tubing. There have been many reported failures of Tig and Mig welds on 4130 due to this exact cause. What you described is commonly called normalizing, and is different then a full anneal. We in the aircraft industry have had to learn the hard way about this material, its easy to work with, welds beautifully, but must be treated right.
Have fun!

-Aaron

[kakarot]

been welding the thing up, me and my friends tacked it all together, and now we are welding it all up. we used 1/2 a tank on tacking and practicing welding. I am a master hole wizard. I think I made most holes, and I have filler most holes. Using er70S2 is pretty easy, I tried a bit stronger material and it became harder to weld because it did not flow as easily.

Anyways, basically non of us know how to weld right, so we are trying our best. Its very easy to make a hole in 4130 1x0.035 tubing even with 1/16 tungsten and welder set to 75amps top.

After we finish the welding, I take some good pics. For now just some spoilers:

Me welding:

[Aerometalworker]

Yep Practice Practice Practice. And while your at it invest in a long sleeve welding jacket. Skin cancer and/or burns isnt fun. Also post weld anneal if its critical.

-Aaron

[kakarot]

some more pics, my friend took them: