Stick on roll bar tubing.....WHAT

Roll bar tubing is only .134" thick. And that is the cheaper seamed stuff. The better mild steel is only .120". If you can't get full penetration with the cheapest of mig welders you are doing something wrong.

And Tig is not the new thing... It came out in late WWII. That was the only welds that would last on chrome moly used on the fighter planes.

Nothing like a big War to get the inventions out there.

Leon

Nonsense, 4130 has traditionally been welded with oxy/fuel;still is, largely due to inertia and the inherant hyperconservative bureaucrat mentality of the FAA types.

HAZ on thin wall 4130 is a nonissue, the alloy was specifically used because it doesn't require pre-heat, post heat in thinwall applications(sub 1/8") Almost all the small aircraft EAA types are oxy/fuel welded. If HAZ was an issue, planes would be falling out of the sky on a regular basis.

Heliarc/TIG was developed for use welding magnesium alloys, aluminum can be welded oxy/fuel using fluxes, magnesium catches on fire. Magnesium fire=disaster. S/F....Ken M

Now that you have our attention, I have a question for those of us with credentials:

Would you weld on steering components on a normally licensed street car? No problem!

Yes I welded the Tri-Pods(front-end) on my dragster.The tubes are CM so I Tig welded them.
I have been a certified Tig,Mig and Stick welder for 30 years.I took a machine shop course in High School and learned to weld. A Supervisor in the weld bay for Stran/Varco-Pruden for 18 years.While employed at Stran/Varco-Pruden as supervisor I was State certified to give the welders there test to get them recertified every 2 years.

Back in the "olden" days before I could affort anything better, I welded a lot of tubing with a stick welder. But, I learned early on that there were special rods available for that job. I used Eutectic "Beautiweld" rods. And, they sure did a nice job. Penetration wwas good, the weld was pretty and no splatter. You will find them at a welding supplier. Cost is high but worth it.

I also acy/fuel welded thinner tubing and yes, 4130 as well. Its not a problem to do, but you need to know what you are doing before attempting. Don't try it unless you know what you are doing.

4130 tubing can be welded with a Mig gun(most oval track cars use 4130 with Mig welds)---but only heavier tubes(over .083" wall) but should be annealed after welding.

I really prefer Tig welding today. But, you need to understand a little metalurgy when Tig welding. Besides, my eyes aren't what they used to be----rod welds aren't bright enough and good Mig welding is too fast for me. The Tig welding is much brighter.

Oh and just a self educated thought . When Tig welding Cover up .
The sunburn comes a lot faster with a tig than with other forms of welding.

What I like best about a Tig,is no splatter coming back on you when you have to weld in tight spots.

It's more who the welder is than which welding machine is used.

That is why most companies (all the big ones) won't hire anyone unless they have a least 5 years on the job experience.With that being said I have seen welders with 20 years experience that can weld but not good.What's so sad is how many that can do a good job that don't,all they are interested in is getting paid.

Bottom line if you are not a good welder or don't have the right welder to do the job on your race car it might be best to have it done. The life you save might just be your own.

Just stay away from the fluxcore crap migs...
I tried to weld with one once and I now understand why people
have trouble welding, it was totally impossible to get a decent weld
and I got my first mig around 1985 so I have some experience

Started stick and gas welding when I went with my dad to a night recreation class at the High School when I was 12. Then took shop in the eighth grade and did nore cutting stick welding and gas welding. The guys who were alphabetically ahead of me got the first turn on the mig and tig and screwed the tips up.

Wasn't until my early 20's I got to Mig weld at my uncles body shop. Later I bought a mig and my first weekend I flux welded and hated the splatter but the welds looked and worked OK. I got set up on a tank lifetime lease deal and never looked back. After switching to 4130 in the race car I bought a Lincoln 175 High Freq. tig. I have sense built four NHRA certified cars and welded on many others.

If my tig sunburns me it is because I am too lazy to properly prepare my tungston. And with that said, if you cannot weld .048 4130 tubing with a 1/8 inch gap and a glob hanging off your tungston get in the back of the line.

The NASCAR guys I know who build cars have always criticized and claimed we are crazy to race with a 4130 cage. They tell me they run 1 3/4" .90 wall DOM mild steel tubing.

My info on the history of TIG comes from the southeastern NHRA Tech Director. He was a career Navy man and is very informative. He and another guy I know worked together testing metals and welds for the Navy.

It is my understanding the first tigs were not High Frequency AC. So how did they weld aluminum and magnesium? I have watched documentories of planes being welded with gas then put in a room where guys heat treated the complete stucture. I also watched the planes crumble when they hit the ground in these films. Later they were tig welding these structures, in these documentory films, just like I was told.

Like MIG welding, there are a number of references sighting "inventors” of TIG welding. However Russell Meredith, working for Northrop Aircraft, was the first to produce a system that was a true production tool applying for a patent in January 1941 (US Patent # 2,274,631, Figure 1 left.) He was concerned about meeting a critical national need -welding light weight aircraft materials. In the first line of the patent it states; “My invention relates to welding magnesium and its alloys - - so relatively low melting point materials may be efficiently welded by an electric arc.” He goes on to say that airplanes are being made of lighter materials and a more efficient method of joining these materials is needed.

Although Meredith's work was done with Helium shielding gas and a tungsten electrode his 4 patent claims are very broad only mentioning an "inert gas" and “refractory” welding electrode. Validating that this was the first workable system and Meredith was the inventor of TIG; there is no prior art sited in his patent.

Let's see who was that that said I was full of crap? Nothing like the internet.

Leon

No offense, but did you read what you posted? It was developed for the welding of magnesium alloys used in aircraft, using DC and helium, hence "heliarc." Just as your quoted source claims, in his patent application. Aluminum was already weldable using oxy-fuel. Magnesium alloys are significantly lighter than aluminum, which is why they were used in aircraft and also race cars until the LeMans disaster in 1955, when mag alloys started falling out of favor in a hurry. S/F....Ken M

as for welding on steering parts on a street car, tear apart any new steering column from any brand and you will find u-joints welded to most steering shafts. also, they are machine mig welded. if it's good for oem, i can't forsee any problems. provided, of course, the welder knows what he is doing.