Weld Quality

[Aeronut]

I‘m practicing welding and wanted to get some feedback on today‘s welds. This is 0.049“ thick 4130 welded with a tig at 49A and 15cfh Argon. Where should I be looking to improve? Is the penetration adequate?

[mike mcs repair]

Plenty deep penetration. Too much is bad on thin tubes.

Might try to back off more slowly at end to avoid the craters

Look good enough to me

But practice on thinner wall like .035, .028”.


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[a.crane]

What are you using for filler rod on the 4130? I have been using er70s-2 because in several places I have read not to use 4130 filler rod unless you are heat treating after. However, was welding a fish mouth sleeve on a chafed 172 engine mount two days ago, have done a few on part 135 planes, and glanced at ac43.13 before I started. It said that I should be using 4130 filler on 4130 tube. Anyone have any guidance on this? I fixed a Maule muffler today and have done several exhaust components in the past, I think the stainless is just as easy as the 4130 to work with as long as it’s clean. I use 1/16 tungsten and filler unless I have a gap to fill then step it up to 3/32, and usually have the argon around 20. I am jealous of the tube kit looks like a fun project!

[dgapilot]

Filler rod should be ER70S2 or S6. Do not use 4130 rod. Try going with a Furick cup and gas lens, either a Jazzy 10 or a Fula 12. That lets you get you stick out farther and easier to get around the cluster. With the bigger cups, you will need more gas flow, somewhere around 20-25 cfh. Either increase travel speed or reduce your amps. Better to increase travel as it will put less heat overall into the joint. If you have pulse, you can also try that, about .7 seconds seems to work for me. I hate trying to use a pedal when working on a fuselage. Recently got a TIG Button, and that thing is great for working where you can’t manipulate a pedal.


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[mike mcs repair]

yes, I hate foot pedal also!

never have been able to make my brain talk to my foot right...

and trying to find a place for the pedal when you are inside fuselage is just another pain....

do you member the game twister? that's what using a foot pedal on aircraft welding is like...

I've always used the finger slider...

I also use the 70s2.... just another example of an error in 43.13 that will never get changed....

[1934A]

What are you running for pps?

[dgapilot]

What are you running for pps?

.7 would be about 1.4 pulses per second


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[Crash, Jr.]

Just my .02 but I find a foot pedal far easier to use. When bridging the puddle from a thicker tube to a thinner tube you have to drop the heat so you don't blow through the thinner tube and do it repeatedly so just for me a pedal is way faster to use. The production welders I work with all use pedals if that makes any difference. That's also on a bare fuselage that's ideally located in a rotisserie jig so obviously you don't have to contort as much to get inside where you're trying to weld.

The production welders also don't opt to use any pulse setting at all because you get better control pulsing using your foot pedal.

[JeffP]

I‘m practicing welding and wanted to get some feedback on today‘s welds. This is 0.049“ thick 4130 welded with a tig at 49A and 15cfh Argon. Where should I be looking to improve? Is the penetration adequate?

I hope I dont upset you but I dont like it. Do you have a pic of the fit up before you welded it. I see a few areas where it looks like you are washing back n forth presumably trying to get the metals to flow. Looks aside you need to cut that apart and see what kind of fusion you are getting or lack there of in the root. I see inconsistant weld beads, weld height as well as width. I also see pits. slice the joint and show us the results. Sorry and yes I weld for a living most days. Good enough, maybe but I know I couldnt send it out the door and expect paid for it.

[mike mcs repair]

I hope I dont upset you but I dont like it. .

Cubs were made from NOTCHED pattern tubes for ever. No fancy fit ups.

All welded in a single day by oxy acetylene. (Swirling to move puddle)

People these days are way to picky.

Those old oxy fuselages can bend without cracking. New TIG ones always crack at weld when tubes bend.


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[Charlie Longley]

I would probably sign this weld off. Keep practicing though!

[JeffP]

I may be to picky and it may be good enough, not something I could sell as appearance is as important as strenght in the structures we build. Put it In a vise get a hammer and give it an old school test?

[Dan Gervae]

I actually gas welded some of my components because early on I was more comfortable with that than Tig....I was ignorant about changing cups, and knowing when to adjust settings when in tough spots....takes practice practice practice. The gas welding adjustments felt much more intuitive to me, and I was having trouble sticking my tungsten in tough spots. I got better though. Also, I was much better at this when I was younger and could see . Lol.

[Crash, Jr.]

Those old oxy fuselages can bend without cracking. New TIG ones always crack at weld when tubes bend.

The test for FAA/PMA weld certification specifically has a bend test and good TIG welds DO NOT crack at the weld. Only bad welds crack.

[mike mcs repair]

The test for FAA/PMA weld certification specifically has a bend test and good TIG welds DO NOT crack at the weld. Only bad welds crack.

My comment was directed at the fuselages YOUR COMPANY SOLD..........


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[mike mcs repair]

I should clarify I mean right on edges weld. Not the weld itself.... when I said AT THE WELD.


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[Cub junkie]

I have a wireless foot pedal. It's nice not dragging the cord around for that. I try to avoid welding threads as there are so many opinions I don't care to debate. The OP is looking for feedback so to me his cluster is not unsafe. If you want to emulate how Piper did it then get to practicing with .035 and .028. There is a lot of .028 in Piper fuselages. On the large cups for more "stick out", I tried 'em and don't use them. I hung around a trade show with Jody from Welding tip and tricks and he sent a kit home with me. I feel like they waste argon. My torch is an HW 20 and a gas lens most of the time but when I need to get in tight I switch to a standard collet and skinny cup that lets me into the deep clusters. Experience counts for this, I've been Tig welding since 1979. The nice looking welds you see from places like Airframes, Univair etc. is by weldors that do it all the time. I don't envy them going for long periods of time head down under the hood. That kind of work is for the younger and flexible. My old bones and arthritis have forced me into building good working rotisserie's and other jigs. Remember that powdercoating and epoxy enamel make average welding beautiful. I stay current on the ox/acet. torch too but thats another thread.

[mike mcs repair]

I have a wireless foot pedal. It's nice not dragging the cord around for that. I try to avoid welding threads as there are so many opinions I don't care to debate. The OP is looking for feedback so to me his cluster is not unsafe. If you want to emulate how Piper did it then get to practicing with .035 and .028. There is a lot of .028 in Piper fuselages. On the large cups for more "stick out", I tried 'em and don't use them. I hung around a trade show with Jody from Welding tip and tricks and he sent a kit home with me. I feel like they waste argon. My torch is an HW 20 and a gas lens most of the time but when I need to get in tight I switch to a standard collet and skinny cup that lets me into the deep clusters. Experience counts for this, I've been Tig welding since 1979. The nice looking welds you see from places like Airframes, Univair etc. is by weldors that do it all the time. I don't envy them going for long periods of time head down under the hood. That kind of work is for the younger and flexible. My old bones and arthritis have forced me into building good working rotisserie's and other jigs. Remember that powdercoating and epoxy enamel make average welding beautiful. I stay current on the ox/acet. torch too but thats another thread.

yes, and TOO MUCH argon will mix with the air and be worse.... more is not always better... can be much WORSE.... practice!

[mike mcs repair]

I‘m practicing welding and wanted to get some feedback on today‘s welds. This is 0.049“ thick 4130 welded with a tig at 49A and 15cfh Argon. Where should I be looking to improve? Is the penetration adequate?

I would gladly ride in your plane welded like you show(probably not with you as pilot maybe )... totally acceptable!

[Crash, Jr.]

My comment was directed at the fuselages YOUR COMPANY SOLD..........

One of these fuselages?



Just messing with ya Mike. I'm sure you've seen some stuff but when you call out someone's welds them are fighting words

[KevinJ]

That looks pretty clean! Any pics of the landing gear showing proper alignment? Could you take that same fuselage with the nice welds, pin some gear legs and show all these guys that your gear lines up? Tired of this talk of your gear toeing in or out. A few min., a laser and a few pics would settle it for good.

[Crash, Jr.]

Let's not kick a hornets nest there. I'm not a representative of Airframes nor am I even all that important. I just sell the parts and from what I've seen and know can stand behind them wholeheartedly. I don't have the time, resources, or pull to take on a measurement project like that for the sake of some petty disputes on an online forum.

The gear in question was a sample size of one. Let's also not forget that BritishCubBloke's Atlee gear didn't fit perfectly. What I can tell you with authority that not any set of gear legs ever has the tops perfectly aligned. It's the nature of trying to line up two little holes 24" apart on the ends of 29" long tubes that are heated past their melting point on both ends. You do your best to get them right but that's all you can do. And then there's the crooked old fuselage that most of the gear gets pinned into....

Let's get back to the OP's questions. This has been enough of a detour for the night.

[mike mcs repair]

Let's not kick a hornets nest there. I'm not a representative of Airframes nor am I even all that important. I just sell the parts and from what I've seen and know can stand behind them wholeheartedly. I don't have the time, resources, or pull to take on a measurement project like that for the sake of some petty disputes on an online forum.

The gear in question was a sample size of one. Let's also not forget that BritishCubBloke's Atlee gear didn't fit perfectly. What I can tell you with authority that not any set of gear legs ever has the tops perfectly aligned. It's the nature of trying to line up two little holes 24" apart on the ends of 29" long tubes that are heated past their melting point on both ends. You do your best to get them right but that's all you can do. And then there's the crooked old fuselage that most of the gear gets pinned into....

Let's get back to the OP's questions. This has been enough of a detour for the night.

Sorry, from your company I’ve gotten lift struts that were INCHES LONGER than they should have been. & wrong angle... parts promised that were sold to others that were made & promised for my project... wing fittings on fuselages that are to narrow to fit wings fittings on coated..........


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[mike mcs repair]

Sorry, from you company, I’ve gotten lift struts that were INCHES LONGER than they should have been. & wrong angle... parts promised that were sold to others that were made & promised for my project... wing fittings on fuselages that are to narrow to fit wings fittings on coated..........


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[RaisedByWolves]

Let's not kick a hornets nest there. I'm not a representative of Airframes nor am I even all that important. I just sell the parts and from what I've seen and know can stand behind them wholeheartedly. I don't have the time, resources, or pull to take on a measurement project like that for the sake of some petty disputes on an online forum.

The gear in question was a sample size of one. Let's also not forget that BritishCubBloke's Atlee gear didn't fit perfectly. What I can tell you with authority that not any set of gear legs ever has the tops perfectly aligned. It's the nature of trying to line up two little holes 24" apart on the ends of 29" long tubes that are heated past their melting point on both ends. You do your best to get them right but that's all you can do. And then there's the crooked old fuselage that most of the gear gets pinned into....

Let's get back to the OP's questions. This has been enough of a detour for the night.

Don’t mean to pick on you guys but your shipping has really gone down hill fast. Used to get parts in a day or two. Now it’s 2 weeks plus.


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[Crash, Jr.]

Sorry, from your company I’ve gotten lift struts that were INCHES LONGER than they should have been. & wrong angle... parts promised that were sold to others that were made & promised for my project... wing fittings on fuselages that are to narrow to fit wings fittings on coated..........

If you have that much of an issue you should probably call instead of airing it out online. That's about all I have for tonight. Hope we can get this thread back on track.

[Aeronut]

This has been a pretty informative thread and I appreciate the comments, including yours JeffP. This is the time for criticism, retraining, and more practice. I can’t learn if I’m not aware of my mistakes. I‘m not touching my fuselage until I‘m confident in the quality of my welds. One of my goals with this project is attention to every detail.

I‘m going to see about cutting the practice piece to inspect a cross section. I‘ve done destructive testing on some pf my welds over the last couple of weeeks including beating them with a sledge hammer and attached a long lever arm to load up the joint. They‘ve all been solid including one that bent steel square tubing I welded it to so that I can put it in the vice. My biggest concerns now are aesthetics and fatigue failures. Something like a fish eye opening up after a few years of flight cycles.

[Aeronut]

Also, I was using 1/16“ 70S-2 filler rod, a 1/16“ 2% ceriated tungsten, #12 pyrex cup with gas lens, stick out of about 3/4 gas cup diameter, and an on/off trigger on the torch. Although I can use my foot pedal on pieces like this the intent is to practice with the same setup I‘ll be using on the fuselage. I‘m also not using pulsing. I played around with it and thought it did offer value but the constant „flashing“ kept my eyes from being able to focus. I‘m talking the pulse flashing not flashing caused by contamination.

Someone brought up fit. I don‘t have any before pics but using my tube notcher I was able to get a reasonably tight fit up. A gap wasn‘t really present.

[dgapilot]

If you want some good practice, buy the “mini hurricane” from these guys https://www.precisiontubelaser.com/buy-now
I think it’s .058 wall, so a little thicker, but gives lots of practice on getting in those tight joints.


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[dgapilot]

Also, I was using 1/16“ 70S-2 filler rod, a 1/16“ 2% ceriated tungsten, #12 pyrex cup with gas lens, stick out of about 3/4 gas cup diameter, and an on/off trigger on the torch. Although I can use my foot pedal on pieces like this the intent is to practice with the same setup I‘ll be using on the fuselage. I‘m also not using pulsing. I played around with it and thought it did offer value but the constant „flashing“ kept my eyes from being able to focus. I‘m talking the pulse flashing not flashing caused by contamination.

Someone brought up fit. I don‘t have any before pics but using my tube notcher I was able to get a reasonably tight fit up. A gap wasn‘t really present.

I like .040 welding wire for the small joints. If I recall you said you were running 15 cfh for gas, with a #12 cup, you may want to bump that up some.

With gas lenses, don’t cheap out! I’ve had the cheap eBay ones and they aren’t worth fussing with. Stick with CK or another name brand.


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[JeffP]

Also, I was using 1/16“ 70S-2 filler rod, a 1/16“ 2% ceriated tungsten, #12 pyrex cup with gas lens, stick out of about 3/4 gas cup diameter, and an on/off trigger on the torch. Although I can use my foot pedal on pieces like this the intent is to practice with the same setup I‘ll be using on the fuselage. I‘m also not using pulsing. I played around with it and thought it did offer value but the constant „flashing“ kept my eyes from being able to focus. I‘m talking the pulse flashing not flashing caused by contamination.

Someone brought up fit. I don‘t have any before pics but using my tube notcher I was able to get a reasonably tight fit up. A gap wasn‘t really present.

If it passes a destructive hammer test I am sure it’s going to do the job it needs to. Welding is like painting in the sense that it takes time to develop the skills to really be consistently proficient. The picture from Crash Jr shows what a skilled welder with good equipment will produce. If you don’t do this routinely you just can’t expect those kind of results. Keep welding, learn with every pass and have fun.


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[fobjob]

Back in the day, (the 1970’s)(sheesh...) when I started teaching myself how to weld airframes, TIG was illegal to use on airframes, (or so I thought, anyway...I’ve been unable to locate any printed evidence of this since) because of microcracks which formed along the edge of the heat affected zone, causing weld failures under bending loads. Since, I have read (somewhere) that that problem goes away if the work is preheated before TIG application. Anyone have any light to shed on this?

[Aeronut]

From what I‘ve read, heat treating isn‘t needed for anything thinner than 0.120“ assuming a starting temperature of the material in the ball park of no less than 70ish degree F. I‘ve played around with hitting the piece with a MAPP torch getting it up to 350F before working it. I can make an argument from an engineering perspective that you shouldn‘t have a dramatic temp gradient along the piece and allow it to cool slowly. However the annealing temp of 4130 is north of 1500F so I wouldn‘t be surprised if a lot of people are woefully under this temp when heat treating implying that at least anecdotally it‘s affect are more myth than fact on thin walled 4130. But that‘s only my opinion.

[fobjob]

I am assuming you mean “pre heating” when you say “heat treating”....??

[Kid Durango]

So I was taught that pre-heat was only really beneficial on high carbon steel. When I read some of the threads it seems folks think it might help with 4130. Am I missing something, and would someone please help educate me. I am a little slow mind you...

[Aeronut]

Fobjob, that‘s my mistake. I‘m conflating pre-heating with heat treating. From what I understand pre-heating is done to prevent a significant temperature gradient and the associated excessive stress ultimately resulting in cracks. Heat treating is done to relieve (relax) stress in the material.

Kid Durango, my knowledge of these process is drawn largely from being an engineer. If there‘s anything I‘ve learned when it comes to heat and metals is that a lot of it is tribal knowledge and established best practices from experience which I‘m sure can be justified using engineering. That being said, I‘ll defer to those with the most experience to answer your question.

[Cub junkie]

Wailing on a welded piece with a big hammer is a feel good test, its not scientific. Standard practices will yield good results. There have been many airframes expertly welded long before some of the current gadgets came on the market. Since you can't build a tube fuselage without an ox/acet rig you can gain some control experience jumping back and forth on your test pieces. Run some beads with ox/acet in addition to practicing with Tig. Get working on 035 wall, if you keep practicing on thicker material you'll slow your skill progress. Your photo is about what my first welds looked like 41 years ago, I went about six months before I started charging for tig welding. I had previous experience with the gas torch. Any welding experience counts.

[Aeronut]

Thanks, Cub Junkie! I was planning on sticking with the TIG setup exclusively for now. I want to focus on one thing at a time.

[ADK_Cub]

Guys kick Cubs around all over the rudder pedals but complain about manipulating a foot amperage control. Lol!

Welds look good! A pointer for chromoly welding, as it doesn’t want to “wet out” or run down into the root of the weld as easily as some other materials, I am conscious of how I grind or clean the base metal in relation to the direction of the scores or scuffs. I try not to leave the marks perpendicular to the direction of the weld as sometimes I see it kinda hanging up the smooth advance of the pool, particularly on the cooler outer edges of the puddle. Maybe over critical but anything helps on tight joints and uncomfortable props and positions to just keep that puddle moving.


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[CharlieN]

I can in no way say I am an expert at welding, only been doing it 51 years, 45 of that Tig welding. I find it interesting the mention of a 1/16 electrode used with the thinner tubes used in aircraft. It is rare for me to run an electrode that large. I find a 1mm electrode my common use size, this is usable for .028 through .065 wall tube. I grind to a long needle point. There are times when doing allot of .028 or welding thin sheet a .020 electrode is more comfortable to get a good stable arc. By thin sheet I mean .009 to .025 or materials such as stainless or Ti that need very little heat. The electrode must come up to temperature to run clean.

Your choice on gas lens or straight cup, each weld has it's different need. I use the smallest I can get a stable flow with. You do not need nor want allot of flow since you are prone to get turbulence at the puddle, the turbulence can draw in the atmosphere which is not a good thing.

Filler rod, rare that it would ever be a larger Dia than material thickness.

Just my opinion from someone who has earned a lifelong living sitting at a welding table.