How to MIG Weld Stainless Steel Exhausts With Flux Core!

If you have any questions or comments, ask away and I will get to them as soon as I see them
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mig weld stainless steel exhaust

[@GickelsGaming]

super, i know this is late to the punch, but one thing to consider when using grinder attachments is to have a dedicated attachment for stainless ONLY. otherwise you embed mild steel particles into stainless, which will cause rust and it will spread :O full time stainless dude :D

[@supernull]

This is a great comment. Dedicated tools, and taking stainless fumes seriously, goes a long way.

[@hannahlaffin4433]

Great video! Very helpful stuff thank you!!! You're gonna go far kid

[@awalk5177]

I have repacked my stainless exhaust box (short system mid engine car) and welded it with a stick welder with good results too. This was years ago, before I owned a MIG set. It works quite well.

[@TylerRogersUSA]

Stick welding has its perks, gappier stainless is definitely one of those cases where stick welding is hard to beat

[@111000100101001]

Thanks for sharing the tips with us!

[@dutch.190e]

Thanks man great video! I had to weld a very small part of my exhaust, so this made it very easy and cost effective :)

[@supernull]

Glad to hear that! You are the exact person this video is for- have a good one Jari

[@bobsgunk1871]

A good way to line up pipe or tubing for welding is nesting it in aluminum angle.

[@supernull]

Thats a great tip, ive been using magnet angles, ill have to try this with some scrap ive got. Thanks for the suggestion!

[@wilsonmessiah440]

Instablaster.

[@SamOHalloran]

Glad I found this, have a MIG, have some stainless welding I would like to do, but Tri-Gas with a bottle is over $300 now. This is an affordable solution!

[@supernull]

This is exactly who this video is for! Best of luck, make sure to wear a respirator and have some airflow to avoid breathing in stainless fumes- very dangerous.

[@dubbified]

Good walk through! I used my millermatic 140 autoset, E308LFC-O .035-Diameter Stainless Flux Core Welding Wire, 0.9mm SONNLER 2-pound from amazon, $18.99. The welder was performing well evecn at the end of a 50 foot thick extension cord 15 amp circuit. Pregrinding/acetone clean, was using a very low speed, Low power, excellent results, no porosity (I cut/inspected it) without the back purging or that paste. Yea, you can see some chudd inside the pipe, bt I'm going from 2", to 2.5 exhaust.. I dont care. Its a turbodiesel exhaust for a ALH, going on my westfalia.

[@supernull]

As long as those welds are all post turbo, you should be totally fine. The chudd/sugaring may present serious risk if flowing before a turbocharger. Sounds like it went smooth for ya! Perfection is the enemy of good enough

[@iiiiii7680]

Pretty good video, decent advise for a beginner

[@jamesward5721]

Just from the sound - and looking at the weld says the same - you'd want to up the amps and use stitch welding where you lay one "Tack" onto the last, aiming for about twice the penetration & a much flatter weld profile. Hold the tack duration as long as the material will take. Doing that will allow you to lay a weld that looks almost as posh as TIG with practise, plus it gives a very very strong, well penetrated weld. Just my 2c. :-)

[@TylerRogersUSA]

This is sound advice! I have learned a fair bit since filming this, and the station I had here was woefully underpowered. Whole garage ran off a single extension cord! Thanks for taking the time to comment!

[@MiataDriverX]

I need to fab up a downpipe and exhaust for my Turbo Miata build, and I feel like this video is by far one of the better ones when it comes to flux-core exhaust welding. I can't transport gas cylinders since my Miata is my only car, so Flux Core was naturally the only solution. I feel pretty well-prepared to start doing practice runs and eventually do the real thing. Wish me luck, lol. Thanks for the advice Mr. Freddie Dredd of Automotive Welding

[@supernull]

Thanks for the kind words! You are the type of person (like me) that this video is for! Let me know how it goes, would love to see the final product

[@TireSlayer55]

Dude just put the gas bottle in the passenger seat and buckle the seatbelt around it 😂 Seriously tho, they do make much smaller gas bottles than the big 4’ tall ones you would see at a shop… a gas supplier should be able to hook you up…

[@MiataDriverX]

Update: I've laid some beads a while ago and took on my first real welding task. Since the exhaust past the Cat on my Miata is one continuous piece, I dropped the exhaust, cut the muffler off behind the rear wheels and welded on a flange. Boom, DIY Axleback. Then slapped on a new, high-flow muffler. Welds went excellent, didn't burn through once. More welding work to do soon. So far, great success!

[@supernull]

@@MiataDriverX Fantastic to hear! If you experience any unwanted drone be sure to check out my other video on removing drone with an additional J pipe

[@marcomourao3711]

Know it's been a while, I'm doing exactly what you are with my NA Miata. I transported a 125 with the passenger seat off and it really is just four bolts. Hope your welding skills has improved much since then. Time for me to try this out.

[@01Snorky]

Great video

[@supernull]

Thanks, glad you found it helpful!

[@randy1ization]

heres a tip for welding small parts onto big parts or together,, super glue them together to keep them in place until u tack them.

[@seanlavelle344]

Thanks for the advice.

[@kinghados]

very good video, thanks for the great help

[@CharlezMalasana]

Thanks for the video. Would love (and suggest) to add links for the products!

[@shawnwagers6061]

At least hes trying and not putting everything about his setup down. I think the dude was working with what he had to get it done the way he wanted it. Wheres the video's of the keyboard warriors?? Trying this?? Thanks for the video dude, and I have welded stainless with 1/16 rods on a 75amp stick machine, headers still holding perfect. Good job dude.

[@supernull]

Cheers Shawn, it's all part of putting content on the internet. Won't help everyone but I'm glad you got some benefit from it!

[@larrytemen4789]

I came here specifically for the comments lol and I was NOT disappointed 🤣😂

[@woodentooth]

Definitely not enough heat in those welds. With the machine set to the correct voltage there is no need to bevel the edges of pipe that thin. Also might want to do a minimum of 3 tacks spread out around the pipe to keep the pipe from pulling when you start to actually lay down a weld.

[@supernull]

Yep I tack 4 times or so, this garage setup did not have enough power to do the stainless wire justice- the concept is the same however. Thanks for watching!

[@nathananspach1739]

Yeah he def needs more heat lol

[@natemartinez4595]

I bevel my exhausts. Especially when welding in place. Helps the beads lay a bit more flat. There's more than just your way dude. Get over yourself

[@isidrosevier1125]

With that stainless flux, did you have to reverse the polarity of the torch. I read on the reviews for that wire that you had too for best results

[@kirkalley3469]

Fun project, it looked cold in your garage. I used to weld a lot of stainless steel at work but I don't have expensive gas tig welders available now that I am retired. One thing to know about stainless is it oxidizes very fast on the surface like aluminum and weak welders can't melt that chrome oxide so it is important to power wire brush inside and out of the pipe joint within 10 minutes of welding then apply the solar flux heavily. Next I find it helpful to put a tiny amount of acid on the joint to prevent oxides from forming during set up. The acid really helps by getting down into the scratches for brazing and soldering too. In cold weather, with a weak weld arc, and to reduce warp, preheat the pipes with propane torch. Get it pretty hot 🔥 but don't ruin the temper of the pipe or melt the solar flux so not red hot. After tacking heat it again after wire brushing the outside and re apply flux inside if possible. Then put the smackdown weld on it. It will be beautifus-maximus. If you do much welding SS even if your welder is not set up for gas, a purge setup is not horribly expensive though required for sanitary welds that require no inside sugaring to prevent pipe cracks and germ pockets. As a side note, only a slight bevel if at all and the joint should be spaced about a 1/16" inch apart to help get penetration and a better clamp is needed since magnets are weak on most stainless steels. Perhaps a piece of angle iron with flat bar welded on to make clamping easier in this case but with weird joints you may need to use a gloved hand to just hold it.

[@luisledesma586]

thanks , a good video, I appreciate the lack of crappy loud music.

[@nathanpearce7169]

If you add about .040 or .035 thou gap and only fill the gap, you can get a super strong and flat weld with thise low power welders. Dont bevel the edges. Youll get a weld that looks like a laser welded it. Looks almost as good as tig. I just did it with my little 110v yeswelder.

[@ericpecana5529]

Nice and pretty.. What brand of stainless steel wire you used?

[@RD-hf6yv]

Wow… I had no idea you could do this

[@brollin2flybrollin2fly49]

Thanks bro

[@randy1ization]

so did u do a fillet weld , then a cap weld, ?

[@s2krookie]

You did the opposite of everything i do. I have the same exact welder. I put my setting on 2 for wire speed and lowest voltage and my welds sit flat. The only time i run alot of volts is if im welding thick metal like mechanic tools but for 1/16" exhaust piping, i run low voltage.

[@supernull]

Interesting, 110V with stainless wire? I'm surprised if so! I wasnt even close to getting enough heat with this setup

[@s2krookie]

@@supernull I buy my fluxcore from home depot. .030" wire. But ya, if i put my heat on even one step above the lowest setting, it puts a hole through the 1/16" steel. I mainly weld exhaust pipes so i always keep the heat at the lowest and my feed on 2-2.5

[@curtiswlkr]

@@s2krookie stainless steel? Or mild steel?

[@s2krookie]

@@curtiswlkr stainless 16gauge

[@TireSlayer55]

@@s2krookiesounds like you’re running regular carbon steel flux wire, not stainless?

[@joseugaz6338]

Friend. Love the video. I just received the exact same 3 inch stainless kit from Amazon. Are you welding down into the seam of both pieces of exhaust or side to side.

[@TylerRogersUSA]

Experiment with what works for you/your welder. I found for this setup it helped to slightly overtravel back and forth seam to seam, but depending on your wire size and welder settings, you may experience something different. Try with a small piece of scrap that lets you see inside for penetration after youve welded and youll know what works for you Good luck!

[@shawnraasch7411]

I know this is an old video and i know you might not respond but this is one of the best videos i’ve found so far so figured i’d try my luck. I’m wondering if there are any cheaper alternatives to the type b solar flux. all i can find are 1 pound cans and i don’t really need that much just because i’m only doing some minor repairs until i get a bottle so if you have any suggestions or links or places to look i’d love your input. thank you and great video!

[@supernull]

I have not personally found any alternatives. What I will say, if saving money is the number one goal, you can skip purging at the risk of sugaring your welds internally, and cracking if putting in a hot system. If it is upstream of a turbo I would not do this. If it is downstream and just a NA exhaust you could probably do it, and if it cracks or causes issues you have to re-do some work... For minor work (after turbos, cats etc) i would just send it

[@shawnraasch7411]

@@supernulli’ll probably just get some and save it just in case, i have an ak tuned rx7 so it sees quite a bit of heat lol.

[@supernull]

@@shawnraasch7411 Better playing it safe and doing some stainless work for friends

[@ajrome1074]

What happened to the wall welds ?

[@MiguelCD74]

What is the wall thickness of the pipe? I have never welded any stainless steel that wanted to warp/flex(but then I have never had the pleasure of welding on any thin material except for decking sheets)😁✌️👍

[@TylerRogersUSA]

Most likely 16 gauge, it wont move much, but when youre looking for a flush fit, every little bit counts. thanks for watching!

[@jamesa6272]

Mig welding Flux core is like gorilla clue for metal. Bonds anything easily haha

[@supernull]

Definitely comes in handy in a pinch!

[@ryanl8340]

Lot of ignorant comments on here. Not practical for a hobbyist to use gas as the setup is pretty damn expensive. Plus that setup doesn't work well if you have to weld outdoors. Everything doesn't have to look pretty to hold together LOL. The comments about your current being low do seem correct though but don't think it's because of your setup. You just need to reverse your polarity and problem solved. And then you can crank the voltage and it won't burn a hole in your material. SS is tricky.

[@larrytemen4789]

And by tricky you mean easy.

[@JB-NZ]

What is this 'Heet' for? Heet + solder flux. Is that just flux, or is that solder paste? I dont quite get the purpose of this, it was not explained in this video... Can you explain it?

[@TylerRogersUSA]

Heet is used to help spread the solar flux, and adhere it to your material (functionally replacing a back purge) While also keeping water/moisture out.

[@ghunt81]

So what does the solar flux do in this application? Does it help pull heat away from the weld joint? I've never used the stuff, read about it but it's not really clear to me what it does since it's on the inside of the pipe.

[@TylerRogersUSA]

That is because we are not back purging the weld, with stainless to prevent oxidation its more important. Back purging (or in this case solar flux) is good for weld strength and also reduces risk of oxidized metal bits falling off in the exhaust while the engine is running , not a big deal unless its before a turbo or something like that.

[@dmdlandscaping825]

What welder is that

[@christopherconkright1317]

If it is not for a car but a charcoal forge fan I just need air to not leak out can I just weld it together?

[@TylerRogersUSA]

For sure! This works for many applications. Be careful if its for a high pressure application, and make sure to check your welds for leaks if possible.

[@topdragster365w]

You used reg flex core wire or a flexcore stainless wire thx

[@madvtecyo546]

Stainless flux core

[@muaddib1116]

Can you explain why you applied the flux to the inside?

[@supernull]

Sure, solar flux is how we are able to "back purge" the pipe without using actual argon gas with a back purge set up. This is what makes sure our welds penetrate, and don't get contaminated as they cool.

[@muaddib1116]

@@supernull Thanks! Is this something that needs to be done because you are butt welding tubes? Or would you do this for welding a t-joint or butt joint between 2 plates?

[@supernull]

@@muaddib1116 That is correct! I am not an expert by any means, but if you are welding with no backing (or through thinner metal into nothing like a pipe) youll want to back purge or line with solar flux. For a T joint or thicker plate, you would probably get away without using it. Solar flux is pretty cheap if you buy in bulk especially and will last you a LONG time.

[@ianbeard3594]

@@muaddib1116 back purging is really only needed for welding stainless to shield the back of the weld from contamination (sugaring) . If the back of the weld isn’t shielded it reduces the corrosion resistance of the stainless greatly & the weld will be prone to be weak & crack & also rust . The solar flux is an alternative to argon gas purging the tube

[@braddo1972]

Atleat you created the bend 😂😂😂😂😂🤣

[@MrDogmeat1]

I have seen other videos using mig, flux core stainless wire with 100% argon gas. Don't know if it's better but it seemed to work well in the videos. Just a thought. Not knocking your set up. Good video and thanks for sharing.

[@TylerRogersUSA]

I wonder why, I have never seen someone use flux + gas. Since you set the machines polarity based on what wire you run, I am a bit intrigued. Either way, glad you enjoyed the video!

[@randycorp5333]

What’s the point of the HEET? And what size wire?

[@TylerRogersUSA]

HEET allows you to apply the solar flux and then disappears quickly due to the alcohol content, I believe the wire was .035 if I remember correctly

[@mozezcen-valley7555]

Is using stainless steel flux core wire will Rust appear just wondering

[@supernull]

If you get quality wire that is real stainless no it will not rust. However the flux coating may look like rust if not cleaned fully

[@mozezcen-valley7555]

@@supernull I ordered stainless steel flux core wire blue demon

[@supernull]

@@mozezcen-valley7555 Let me know how it goes!

[@phiksit]

Make sure you don't clean the pipe or weld with any carbon steel wire brushes, or you'll get rusting.

[@markbrown1609]

I know a guy welding handles onto an empty 50 gallon drum, his supervisor told him the drum had a non flammable substance when in fact it had been full of acetone. it exploded and killed him instantly

[@supernull]

Keep acetone AWAY from you- cant stress that enough and your story continues to prove that! Sorry to hear

[@austinlane5533]

You KNEW a guy who's at 99% fault for not double checking his work materials. You never trust someone's word like that.. or it costs you and you only. Any half way competent welder knows this is an elementary level error..

[@richardrussell4065]

Trust no one

[@larrytemen4789]

Never believe anyone. Always check yourself before welding. That’s a Darwin Award deal. Also, never weld anything that is a sealed container regardless of what’s in it.

[@anthonynapier4668]

👍

[@TheProchargedmopar]

👍💪

[@weldmachine]

You either need to crank the Amps up or Buy a larger Mig Welder. By just listening, you can hear your welds are way too Cold ?? Is this Mig Welder a Low Amperage machine or are you struggling to get enough power out to your shop ? Not knowing your current set up, it's hard to tell why you are welding with such Low Amps ? Wish you all the best with your channel Keep at it and it will come together with more time and practice.

[@supernull]

That's the truth. This garage setup was severely underpowered. Putting together a proper shop with 220 now!

[@weldmachine]

@@supernull Happy to know you are putting together a decent power supply to your shop. When you run the power out to the shop for your Welding Machine try to run as larger cable as you can afford. Not sure of your cable sizing where you are ?? But run at least 4mm cable or larger. 10mm would be best. This is a great place to start. IF you run a Single Phaae Welding Machine. Don't use any Extension Leads. Especially on a Transformer machine. Wish you all the best with your upgrades 👍

[@experimentandoenlacocina5399]

What voltage or amperage did you set for this?

[@supernull]

Every machine is going to be different, test on some scrap material that matches the profile of what you are welding to and youll be in great shape. For me specifically- its hard to say, but way too low of a voltage as it was a 110V welder on a long extension cord. With stainless you want to run as low of a heat as you can, but I believe my wire speed was around a 2-3/10 and my heat at a 7/10.

[@turbovicsatx2910]

You need more heat the weld is tall

[@supernull]

You are correct, stainless needs more heat than my 110 welder can provide (on an extension)!

[@2012isRonPaul]

and what is solar flux and heet in europe?

[@TylerRogersUSA]

search for solar flux on amazon or ebay, should be available worldwide as far as i know.

[@jimurrata6785]

Heet is sold as gasoline dryer. It is pure methyl alcohol.

[@OleUnreliable]

I'd wear a respirator with the proper cartridges when welding stainless. Those fumes will fuck you up over time.

[@supernull]

I appreciate the concern, I have since added an exhaust system and respirator. Breathing poison is not too high on my to do list

[@deankay4434]

My youngest half brother is Fucked up to start with. So, does it still make a difference? He can’t weld either, plus he took my 68 Dodge Charger and wrecked it before he could use the fuel I had in the tank. Yes, stole it because he had someone drop him off as I lived 18 mile from no one in the country. I was plowing since 5AM for $1 per hour, he worked in a toll booth on the interstate! How hard is that! Had ticket on one side, the screen told him how much change to give on the other. Never leave keys in your car even when your closest neighbor is 8 miles away. Bastard never said he was sorry after siding sideways into a tree in a grab-wire fence. 6 months in county, 120 civil service, 3 months probation.

[@Wide_open]

Yea I’ll stick to using gas haha

[@ze_german2921]

You don’t need to back purge unless it is food grade

[@supernull]

You technically don't need to even use stainless wire, but if you're going to do the job you may as well do it as best you can

[@fionagardner4257]

There is a much better way, I've been doing it for years commercially, just use Helium as the shield gas, stainless wire you get super clean welds and a bonus of pretty colours as well.

[@fladoodel]

Really you can use helium as a shielding gas? Fascinating

[@jimurrata6785]

@@fladoodel TIG welding, when it was introduced by Linde, was called Heliarc welding for a reason. 😉 Helium is another noble gas, just like argon. (has slightly different properties but serves the same purpose)

[@mikeeagle2653]

It’s says lacquer thin right on the side of the can. Lmao 😂 not acetone. And you’re supposed to mix solarflux with alcohol.

[@supernull]

hahaha, yep lacquer thinner is correct but they're very similar! I've been taught solar flux is mixed with Heet as it contains methanol, evaporates quickly, and extracts any water that may be present. BUT you are absolutely right, alcohol will work great too if you don't want to use yellow Heet.

[@mikeeagle2653]

@@supernull no lacquer thinner and acetone are not similar at alll.

[@mikeeagle2653]

@@supernull read the directions right on the solar fix can. It tells you right on the can to mix with alcohol. The alcohol will remove any moisture from the weld. Alcohol is like $1 for a big bottle. That heat is like $3 for less then half the amount. Waste of time and money

[@supernull]

@@mikeeagle2653 I'll have to try it out and do a side by side comparison, thanks for the tip

[@supernull]

@@mikeeagle2653 as a reference though, if you check the solar flux website they recommend methyl alcohol for best results.

[@mikemakuh5319]

If your going to weld stainless you gotta use a tig!

[@gobear83]

Looks cold in your garage …

[@TylerRogersUSA]

Very. This garage had no power and no insulation- my new setup is much, much better.

[@CL9k24a3]

You would be better of with solid ss wire and straight co2.

[@jvazquez53]

Cool video but SAFETY FIRST! No guard on that grinder....

[@supernull]

Very true, need to be better about that... Do as I say, not as I do

[@ericdolan2130]

I'm a welding inspector, and I have three customers that have employees missing all or part of their thumbs....Guess how?

[@supernull]

@@ericdolan2130 Ill give you a thumbs up before I can't, thanks for looking out! I need to be better about using my guard

[@timNgarland]

Tell me you’re not a welder without telling me you’re not a welder 😂

[@chiathach206]

You need practice

[@mwyson4095]

I'm sorry but those welds are ugly. I think I'll buy a bottle of 98/2 gas.

[@TylerRogersUSA]

I dont disagree! More for in a pinch or not having the right tools for the job- a proper gas setup will always outperform

[@antonuskov4376]

Go to professional welder

[@2ndshiftaudio300]

Pressure test it. I bet it leaks like a bitch.

[@supernull]

Capped it and filled with water to locate pinholes and it held fine, I don't have the means to pressurize much more past that though unfortunately

[@danlossk1435]

Bruh. That looks like shit, tig is only way, this can be use for drift car kind of project where u know u gona fucked up whole car into the wall. Stay safe

[@ioijiopjkiopjkp]

wtf did i just watch

[@gocart09]

That's way to much work for something that looks like a boogers

[@randyhodder8186]

This guy ...go back to school...

[@michaelangelo8001]

No offence, but I just have to say that is some of the poorest welding I have ever seen...

[@supernull]

They definitely aren't pretty! At the time, thats the best my tools could do- and they've held up surprisingly well. But yes, theyre rough

[@michaelangelo8001]

@@supernull I'm just saying; you may not yet be experienced enough, to be teaching welding lessons...

[@supernull]

​@@michaelangelo8001 This video is only to show people that gasless stainless MIG is possible, by no means is it done perfectly in this video! Thanks for the feedback

[@michaelangelo8001]

@@supernull Well I suppose you accomplished that end, at least to a degree... However the title is quite misleading. Surely you would agree that the results are a long way from TIG welding.

[@supernull]

@@michaelangelo8001 without a doubt far from TIG-! I'd change the thumbnail but I think its too funny. Thanks for taking the time to comment, hopefully you stick around and my newer stuff will resonate a bit better as I improve

[@Deathwish98]

Could I get the settings in writing please

[@supernull]

Every welder will be different, do a few tests on some extra pipe to dial in. Low wire speed, high heat, short passes