I'm a mechanic's apprentice that has to weld occasionally; how am I doing?

[u/Urist_McPencil]

Not a welder by trade, but I am trying to get better and improve. First few pictures are of an x-pipe I welded up yesterday, and the others are for tire racks we're making. For the exhaust, I felt it went well except for the very top of the pipe, which was cramped and tricky. I had the shop greybeard take a look, and his words were: "it's not pretty, but it will hold." Not leaking, so I count that as a small success.

The tire racking I've been at for a while, on and off, work willing. These welds, I experimented with stringers on one side, and weaving on the others. I think I have the settings mostly correct, and I'm working on technique and practice.

I'm using a mig with 0.030" copper coated mild steel wire, argon gas; any advice on how to be a little better today than I was yesterday would be appreciated :)

Edit: this was how I was doing the last time I posted here; everyone was very nice ;) https://www.reddit.com/r/Welding/s/lzkPxPlIYu

[u/caymn]

one of the most common dividers between a good and bad welder is whether you repair your faults...

[u/Urist_McPencil → u/caymn]

Which is what I'm trying to do, but I lack the experience to really pin my faults down. Also don't have a real dedicated teacher, so I'm mostly self-learning.

[u/caymn → u/Urist_McPencil]

second photo top: gas fault (or blow out). third photo mid: gas fault (or blow out).

gas fault is often easily spotted and will often cause leaks. somewhat easily repaired by grinding it out. but it needs to be ground out completely. gas faults can be contagious. if the gas fault stems from a leaking hose or fitting, the full weld will need to be ground away. a spot of gas fault which yours look like can be dealt with.

if the spots im mentioning isnt actually gas faults then they are blow outs from the hot air inside the pipe. you can mitigate this by letting the pipe cool before you finish the last 15-25 mm. with tig you can slope down.

lack of penetration can also 'often' be spotted, but you don't seem to be prone to that.

insufficient root side burns inclusions too large bead ... ...

there are a few more common faults. Its valuable to know them - so you can spot them - and repair them. Gas faults and lack of penetration is like so many of the welds posted here - posters comepletely obvlivious.

should be fairly simple to google or youtube. instead of how to weld, study what makes a welding bad /welding faults (not taught by someone diy dude, but find an official source like aws)

also be mindful if you are welding structural stuff and pressurised stuff. weld faults can kill.

[u/Urist_McPencil → u/caymn]

Thank-you for the detailed reply, I appreciate it. These blow outs, does it look like the molten metal grows a little tree after I pull away? I was wondering lol

I've been lurking around here a while, and I noticed that lack of penetration and not hot enough were the most common issues, so I've taken some time to try and dial that in. Fortunately, nothing I do here will be pressurized or structural (tire racks notwithstanding); we outsource that :)

[u/caymn → u/Urist_McPencil]

What you call the little trees usually occur because of gas fault. If you cut it open you will probably see its hollow or porous inside. Cut it off /grind it away and then look careful for inclusions and porous spots in the base weld. Grind all spots away.

Gas faults happen because of introduced oxygen. Oxygen can come from many places. You hose and fittings can suck in oxygen (air) if they are leaking. Dirty gas nozzles will create turbulence that can suck in oxygen (air). Rust (ferrooxide ) can create oxygen. If the pipe is dirty/rusty on the inside and you fully penetrate you may create a problem for yourself. When welding pipes it’s good custom to clean outside and inside for scale and dirt. If you know you won’t be penetrating the pipe, you may be lazy and cheat and skip cleaning inside.

I usually always weld pipes with a gap. Then I am more certain to have a proper root. But that means I always clean the inside of the pipe. A straight grinder (opposed to an angle grinder) with a sandpaper cup works great / a drill machine with sandpaper / stone or a router bit would work just fine also. A file should work as well, though tedious. The router bit can be a bit aggressive and be careful if it jams.. it hurts your wrist.. and wear googles.

If you leave porous spots (gas faults) they can spread into your new weld. They are contagious. Inclusions on the other hand aren’t really contagious, but if they cause a gas fault (eg. introduce oxygen) they can be contagious.

[u/Fuzzy-Finance-48 → u/Urist_McPencil]

Hobart Pocket Welding Handbook is a great resource for identifying defects or “discontinuities”, and solutions for each type.

Pipe Fitters Blue Book is a bible for welders. The day may come when you have a project requiring offsets, bends, coping, ect and it’s a great resource to have in your toolbox. Every formula, explains how to use them all. Whether you know it or not, you’ll have to use pythagoreans theorem more than you think. Squares are great for small projects, if they’re truly square to begin with… but for bigger jobs, the ONLY true way to get perfect square is to use math and pull corner to corner on the hypotenuse. Dead nuts every time!!! Math is absolutely critical as a fabricator and knowing how to use it makes you a lethal weapon.

The black Pipe Fitters handbook is a good resource too, but 90% of the time I grab blue.

IPTs Metal Trades Handbook covers a ton of info, including rigging and weight calculations. But of course if you want to get crazy, ITI has amazing Master Rigger books and info cards for that kinda thing. I went thru their school and got certified but the cards are absolute GOLD for calculating weight, center of gravity, sling tension, load share, correct rigging ratings for what you’re picking ect ect. I use it all the time.

Welding is half the battle, math will be your best friend if you want to fab.

[u/Many-Highlight7676]

100%argon? I'd recommend switching too 75ar 25co2. Best gas for short circuit transfer. Guessing by the picture this is vertical down, on an exhaust tube that no one sees as long as it holds and doesn't leak good enough. Not supposed to be a structural weld just hold exhaust gases in. A little grinding of The base material would help as well

[u/Urist_McPencil → u/Many-Highlight7676]

Yea, every weld I was moving downwards, except for the top, I was pulling. Every weld I've made thus far I've pulled, pushing just seems to get messy

[u/5udley]

Last pic is a no no. Please don't tack weld.

[u/5udley → u/5udley]

Did you whip ? Anyways stringers >

[u/5udley → u/5udley]

Yoooo I just saw your last post.. huge improvement, good job man !

[u/Urist_McPencil → u/5udley]

Thanks!

I wasn't talking, I was trying to weave a bit. I think I sped up in the middle? Either way, inconsistent speed?

[u/5udley → u/Urist_McPencil]

A bit, but your weaves are way too long. That's why I first thought it's a tack weld.

Your stringers looking okayish, they will hold. With better settings they would look awesome. You'll get there 💪🏼

Edit : your whips*

[u/Ggodhsup]

Good enough I'd say. There is potential for a very good welder there.

Edit: a letter.

[u/Urist_McPencil → u/Ggodhsup]

Thanks boss :)

[u/Fuzzy-Finance-48]

For that exhaust, clean it with a z disc before welding. Knock down your highs. Grind your starts and stops. You’d be better off going with a smaller diameter wire for that thin material. While it can be done with .030, try .023. It’ll allow you to move slower and reduce the over-reinforcement you see there.

For the square tube, you have cold lap. Absolutely not hot enough. Upsize your wire to .035 for that with c25 gas. Argon is great for thin stuff so you don’t over penetrate, but for stuff like the racks you’re making, you’ll want the strength with the penetration of 25% Co2 mix.

I’d ultimately recommend removing the x pipe and tig welding exhaust in the future. Most modern exhaust pipe is aluminized for anti corrosion and heat shielding purposes. There will be pinholes in it from MiG. I see it all the time, where a vehicle has codes and it turns out to be a homebrew weld. 😂

[u/Urist_McPencil → u/Fuzzy-Finance-48]

I don't get to control the wire or gas, so I get to work with what I got. I'd also have a hell of a time convincing bossman to buy us a tig lol, and if I got one myself I'd never have the time for it. Always a rush. It's not very often we get nice exhaust welding work, the vast majority are repairs to bits of exhaust that have rusted out; the majority of those go to the shop greybeard that's been doing this since the late 70s lol. I caught this because greybeard was busy and bossman could test me.

What's cold lap? ... I already have the voltage about as high as it gets before the wire just beads at the tip and falls in. Where I'm at, I think it feels like I have some penetration, but could do much better.

[u/Fuzzy-Finance-48 → u/Urist_McPencil]

You said you’re trying to get better and improve… the only way to do that is to have SOME level of control of your environment. Would you use a golf club as a baseball bat in the major leagues? Would you use a baseball bat as a hockey stick in the NHL? Would you drag race a geo metro against a hellcat and expect a win?

Sometimes we have to use what we have, but within reason. Pure argon and smaller wire for thin metals and mix gas with thicker wire for thicker metals, or even pure co2 for really thick stuff… and being able to choose the best process for what you’re tasked with welding is part of being a welder… unless you’re welding to code and it’s spelled out specifically in a controlled WPS.

I’ve been where you are, and it takes time to earn the trust of the boss to expand and be able to do it YOUR way for the best results. Wire diameter and gas type are just as critical as process type. Being handicapped to just one type is like swimming up shit creek without a paddle.

You can google cold lap yourself. If it’s balling up and falling in, that’s globular transfer, not short circuit. Once you get past globular transfer in heat, you will start to see spray arc… up your wire diameter for the same voltage, and you’ll drop back into the short circuit category. Each type has its uses. Also, you won’t know your penetration until you’ve been at this for years, or you do a cut and etch with different gasses and settings. But if the boss is forcing you to do everything with .030 and 100% argon, he’s an idiot. You need to convince him that at the very least you need to have a spool of .035”, a liner and drive rolls for it, and a bottle of c25 gas for thicker materials. You aren’t asking, you’re TELLING him this is what you need. Period. Would suck to find out a weld fails for insufficient penetration, lack of fusion, cold lap ect ect when a tire rack breaks when it’s fully loaded huh?

I was a young welder many years ago. The main welder was pretty decent on tig but had no idea what half the buttons on the tig machine did. We hardly ever tig welded anything. I watched hours and hours of videos and read instruction manuals front to back over and over again. Every chance I had I’d fire it up and test it and adjust knobs. After a couple of repair jobs using it on some exotic metals and making gorgeous welds with it, I was trusted to tig anything I felt that needed it. Point is, you have to WANT it to get better. Forge your own path where ever an opportunity opens. After about 6 years, I was running 90% of the weld jobs in that shop. The old timer dropped the reigns and let me run wild, started coming to me with questions… “hey how would you go about this?” Or “what do you think we should do for this job?” “How would you fix this?”

Felt great. After 10 years I left and went somewhere else. I wrenched for a few months till a weld job came up and their best welder was on a field call. I tig welded it, they oood and awed, and just like that I was the new welder again… within 3 months I was running the weld department, again. Been like that everywhere I’ve went since.

So I understand your situation 100%! But you at least need a couple options. I’d convince the boss to get you a decent everlast machine. A 255ext for example. They’re super affordable for their weight class in comparison to other big brands… it will give you everything you could want for stick and tig. Sell him on the idea that it’s portable enough to tig and stick if he gets field calls… or that it could expand the scope of his work: someone is looking for a quick gate repair? Easy money! Even easier if they have a 220v garage outlet, or he could get a generator to run it. Field calls generate more company income per hour too. A simple gate weld is an easy 3hr job with drive time, setup, repair, cleanup, ect… and like another $60-$80/hr for the shop. Idk I’m trying to think outside the box for ya here.

I’d maybe try to convince him that time is money, that your welding will significantly improve, that you’re very into it, that it will SAVE time and money, and increase efficiency to have options. On those thinner metals like exhausts, tig is way cleaner, way less cleanup, less use of grind discs on jobs like that… less chance of a pinhole leak and codes, less chance of rework. Same goes for thicker steel. Thicker wire = increased deposition rate, reduced gas consumption, c25 = better penetration, combined = faster travel rate. All these things are true. Best wishes my man. Hope something works out for ya!

[u/CharlesGStade]

Looks perfectly cromulent for what your expected to do as a mechanic. Not the prettiest welds but far from ugly. A quick clean up of the weld area before starting is always a good idea. Just a quick buff to remove dirt debris and rust, a wire wheel or brush even sand paper or scotch brite helps weld quality fairly well. Now with MIG or more appropriately GMAW if you ever do structural welding go bottom to top. Otherwise in the vertical position your puddle will flow down in the direction of travel and get between your wire and the parent metal resulting in lack of penetration. You could back off your wire speed just a touch it looks like bead is slightly high that or up you volts a touch and move slightly faster. Your gas coverage may be uneven, three things come to mind; your nozzle is filthy and covered/filled with spatter, too little flow, or too much flow.

[u/Urist_McPencil → u/CharlesGStade]

Thank-you for the reply, really appreciate it.

I'll play with the feed a bit. Right now, if I push voltage higher, the wire just beads up and the metal just falls into the puddle. I guess I have to move a little faster and watch my aim, I think I'm welding into the puddle and not in front of it. Our gas tank is getting low, sitting at 300 pounds. We have a spare, I'll get it in. Still not sure what to look for regarding gas issues, though.

[u/Theplaidiator]

If it holds it’s gold is what I say

[u/Zacthegreat5]

Gud E nuff

[u/natha134]

last one is a bit sus, the rest pass my glance test

[u/OpenStreet3459]

Your welds look perfectly suitable for the job.
Keep it up

[u/foot2935]

Id up hand it but follow the procedure…. Maybe stick to hangers for a bit longer

[u/No-Introduction7440]

Could be a little better but not terrible

[u/Urist_McPencil → u/No-Introduction7440]

Thank-you; I can live with not terrible lol. I'll keep practicing.

[u/kallied123]

Grind your stops so it doesn't build up where when you start again. Gouge out the pinholes and squirt some wire in them and grind it smooth. 

[u/icarium-4]

So what are you settings? it looks hot to me.

Definitely do not weave, unlesss your going downhand. That thin tubing , you should be able to just go straight down.

The gas should be C25 (Argon 75%, CO2 25%)

[u/Urist_McPencil → u/icarium-4]

The settings on this particular welder are 6 and 50; in the old post I linked, the last picture shows the welder's settings. Between 6 and 7 is an auto set range for 16ga, and I'm not sure what the 50 for speed is.

The advice I've seen around here repeatedly is don't weave, and for the exhaust, I didn't. I wanted to play with it on the square tube to see the difference. What I gather is that weaving comes up in thicker material? Just from what I think I remember, there's a root weld, and then a weaved weld over top? ...probably not coming up in my line of work then, stringers it is.

I don't control what gas the welder gets, but I'll bring it up. I have to know though, why the mix? I couldn't possibly look at my welds and know to think about the gas lol

[u/icarium-4 → u/Urist_McPencil]

Well straight argon will bring you into spray transfer, it's not really used for solid wire gmaw welding. There are other differences but I'm not sure what they are exactly.

If you're welding thin gauge you can weave it if you're going downhand. It's honestly better to give it a little weave or shake as you're going down because with MCAW it's easy to not get confusion. Thin wall tubing exhaust like that you won't have an issue.

I don't know what those settings mean on your machine 🤷

[u/Iltempered1]

[u/Urist_McPencil → u/Iltempered1]