Video series on TIG welding thin wall aircraft tubing

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spikews

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I remember back in the 60s it was bad to heli-arc a/c tube (4130) CM. Now Heli-arc is called TIG. In M/C (chopper) forks it would snap about a 1/4" to 1/2" from the weld. Has something changed? The long forks had an ability to flex w/o remaining bent. Was there a difference in welding process from then to now. All a/c were oxy/acetylene welded in an earlier time. Can you help me out on this? I'm confused.
 

Little Scrapper

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I remember back in the 60s it was bad to heli-arc a/c tube (4130) CM. Now Heli-arc is called TIG. In M/C (chopper) forks it would snap about a 1/4" to 1/2" from the weld. Has something changed? The long forks had an ability to flex w/o remaining bent. Was there a difference in welding process from then to now. All a/c were oxy/acetylene welded in an earlier time. Can you help me out on this? I'm confused.

For starters it’s not apples to apples comparing 1960’s TIG machines to modern day TIG machines.

Back then they were considered high tech but were dreadful machines. Transformer machines, hundreds of pounds, arc stability was a major issue, and torches were very much a problem back then. Torches use to be something you would send in and they would rebuild.

Heli-arc / TIG etc, mostly the same. It was invented primarily for aero space to weld alloys and magnesium. It was a godsend for that.


Miller changed the game with the Square-Wave, and the industry really started to change with the invention of inverter machines and printed circuit boards mostly made in China. Prices started to drop annually and “average people” had access to a great product that worked great with less skill.

Skilled TIG welders were a rare breed back in the 60’s. So if someone was TIG welding choppers there’s a good chance he wasn’t a skilled aero space welder. I would question the person welding it and ask about his prior experience. Just a guess.

Properly welded 4130 cm with any modern day TIG machine, including the cheap Chinese machines, produce unbelievably excellent welds. The arc is very stable and manageable. More expensive machines can dial in amps down to 1/2 a amp. That was unheard of back in the 60’s, amps were hard to control with any consistency.

So while I can’t speak for a chopper experience in the 60’s I can assure you the modern day TIG machines are excellent and we are fortunate to be able to have them so cheaply.

Gas welding will always be a great idea. I built my entire truck racking system using gas welding just because I love the process. It gets abused daily in my business and there’s zero signs of failure.

I wish more people would experience gas welding. It’s really fun and produces excellent results.

Mike
 

Little Scrapper

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I've watched most of the videos and will watch the rest as time allows. I appreciate the time you've taken. Unfortunately I resemble the Netflix binge watching comment, but I'm deep into my kitfox project and have a welder lined up so not going to go buy welding equipment at the moment. But it's something I've wanted to learn and your video series makes it look like it's in reach. So thanks again.
I got sucked in to Blacklist. I don’t regret it, That was a brilliant show.
 

spikews

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Thank you. That explains a lot. I figured that the industry had come up with a way to utilize TIG or it wouldn't be used. I've only welded with acetylene. And that was a few years back. I'll try it again and see what I remember. I still have "o" & "oo" tips. You gave me a great idea about using mig wire. at .035" or .030" to use as .060" stick is as small as I have. I have scraps of 4130 CM to practice with. Spike
 

Little Scrapper

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Thank you. That explains a lot. I figured that the industry had come up with a way to utilize TIG or it wouldn't be used. I've only welded with acetylene. And that was a few years back. I'll try it again and see what I remember. I still have "o" & "oo" tips. You gave me a great idea about using mig wire. at .035" or .030" to use as .060" stick is as small as I have. I have scraps of 4130 CM to practice with. Spike
I just love gas welding! Good luck and have fun! When it comes to gas you may find .035" a little on the light side. For TIG, yeah, perfect! But gas has a large heat envelope so dial down the tips if you can. When I use .040" for gas I use a custom tip I made for the Meco where I use a drill bit and made my own in between size by drilling a new orifice.

.040" is also a great option for 4130 gas welding. ER70-S2 can be sourced locally.
 

wwalton

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I have to chime in again. Had another few hours of practice today. The "contract" idea of setting a realistic amount to weld is gold. I was just on the bench but I realized I had been moving my head down and across to weld. So I used a few clamps to mimic a vertical tube and did the 1/8 at a time bit keeping my head still. Much better welds...slower but that makes sense too.
 

Little Scrapper

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So I should buy (or order) .040" sticks like you had in one of your videos? It amazed me how much I learned from them. Thank you.
Depends on your goal. I would certainly recommend 040” if your willing to put in the time to experiment. I do use 1/16” successfully on gas, but it depends on what I’m doing.

I love .040” and always have it on hand.
 

Little Scrapper

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I have to chime in again. Had another few hours of practice today. The "contract" idea of setting a realistic amount to weld is gold. I was just on the bench but I realized I had been moving my head down and across to weld. So I used a few clamps to mimic a vertical tube and did the 1/8 at a time bit keeping my head still. Much better welds...slower but that makes sense too.
Excellent. Sometimes it helps to do a count like a 4 dip count.....dip, dip, dip, dip.....stop. Experiment, it's your art so find a way that works.
 

Little Scrapper

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WWalton

Just remember the cooling part though. When starting on a pre-existing bead you need to back heat it a little so it blends in with the new weld or else you have a permanent cold spot. Now, don't freak out about what I said here, you just want to have a nice weld puddle on the old weld before you start moving. Once moving......keep moving.
 

F3A-1

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You demonstrated a number of new ways (to me) of approaching some of the problems of welding up a fuselage. I followed the entire thread, and as expected, I learned something. OK. I learned a many things. This was material not in the "search" functions of Y/T.
Great job presenting.

Thanks,
Lex
 

wwalton

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Just remember the cooling part though. When starting on a pre-existing bead you need to back heat it a little so it blends in with the new weld or else you have a permanent cold spot. Now, don't freak out about what I said here, you just want to have a nice weld puddle on the old weld before you start moving. Once moving......keep moving.
Yes actually this is another "break thru" thing for me. I was trying to get around a weld without stopping if at all possible. I just didn't realize how silly that was till you pointed it out. And now seeing the previous puddle melt and getting into a rhythm is going to take a lot more practice.

I need to order my material for the Practice jig/fitting you designed and get after it!

I'm enjoying this learning process...most of the time. Burned a big hole in .065 today trying to weld the backside of a tube....seemed so easy till I thought of it afterwards...duh kinda hard to see the metal getting ready to melt from above the joint.
 

Little Scrapper

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Yes actually this is another "break thru" thing for me. I was trying to get around a weld without stopping if at all possible. I just didn't realize how silly that was till you pointed it out. And now seeing the previous puddle melt and getting into a rhythm is going to take a lot more practice.

I need to order my material for the Practice jig/fitting you designed and get after it!

I'm enjoying this learning process...most of the time. Burned a big hole in .065 today trying to weld the backside of a tube....seemed so easy till I thought of it afterwards...duh kinda hard to see the metal getting ready to melt from above the joint.
Don’t forget, you can have your hood down and ease up on the pedal so it’s just keeping it warm and this allows you to breath for a second and look at what you’re doing. This is only for practice, not something you want to make a habit of though.

When that puddle is puddling, it’s best you move along right away. Haha
 

wsimpso1

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Loving the video, even though I am a dedicated gas guy. I usually do about 5 or 6 half-days teaching gas welding at OSH. You have added to the teaching tools for me. I love how heat, getting close, good position, cooling with the rod, really do follow the same schemes. And now, when folks ask me why not just TIG, I have one more answer - TIG is more sensitive to position. The openness with gas is a plus.

I also love how you present travel speed as the product of the other variables. How does the welder know how fast or slow the inputs are allowing them to go? With gas, when I started emphasizing watching the leading edge of the puddle, their travel speed started taking care of itself. Yeah, another sub-conscious skill to develop... What does the TIG welder look at to know they are moving too much, too little, about right on travel speed?

Oh, your wife must be a really good sport on all of this! Thanks to her too.

Thanks again for good videos!

Billski
 

TFF

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There is a British guy on YouTube building roll cages and cars. He has a couple of tunes in his head that he thinks or hums to keep the rhythm. No solos.

Taking the bead in short spurts is a lot of help stopping burn through. Stop and let it all cool down. Long runs get hot and that’s when I drop through. Video TIG stars tend to be concentrated on high end welding jobs like heat exchanger tubes or food plants. Not as many thin examples. Thin to the industrial guys is 1/8”. Not that our size is only used by us, but it is special use.
 
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