Help me with my first ever mig welds, why do they look like Swiss cheese and will I ever improve (cry for help after being demolished on Reddit)

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If you don't get any joy here try the mig welding forum, they are a pretty helpful lot
 
Where is the information required, type of MIG, current, feed speed etc etc. Half the battle is getting the right welder and setup correctly, then you are in a position to learn. Best thing to do is get an evening class in welding, it is how I was taught gas, MMA and TIG other wise it is like teaching yourself to drive and expecting to pass the test.
 
I haven't done any MIG yet still on MMA, but that looks like not enough penetration (beads sitting on top too much) so not enough amps and also not enough gas flow (all the oxidation). The long one on the left is obviously closest but it looks like you need it to dig in more (and can then probably move a bit faster), and it's still not been protected enough by the gas. But that's me as a very amateur learner welder guessing really. As Tris said, the 'MIG welding forum' is a great source of better informed advice.
 
Welding is a learned art- and takes lots of practice to learn lol
You have some porosity (usually an unclean surface, and/or gas flow is wrong (usually too low, but a extremely high gas rate can also cause it) and your 'heat'/penetration is too low on the ones on the right- current is too low

(I spent 3 months learning as a elec fitter apprentice how to weld, and that was 5 days a week, 8 hour days!!!)

Just welding a surface weld only teaches you so far- a better way is get some offcuts/scraps and weld them together, then break them apart again, to look at things like penetration etc

You actually have some 'reasonable' looking welds there as well so I suspect a lot is in your technique (with some pretty ugly ones as well but if this is your 'first time' nobody should expect perfection!!!)

I been welding on and off for over forty years, but even then I have to 'run a few practice beads' before doing any serious work if I haven't done it for a while, especially on a 'new machine'- as every single machine will do it slightly differently

So make sure that surface is CLEAN (and that includes things like oil from your hands even can cause that porosity- and even from earlier welds- clean before each new weld!!!) and experiment with your feed rate, amps, gas flow and the 'speed' of your torch travel... the best one is right at the top)


A lot of them look like the travel speed of the torch is too fast and/or too slow a wire speed (especially the 'chicken scratches' on the right) and those that are 'sitting on top' without good penetration- that can be too low on amps...

The sound will often give you clues as well while laying a weld- a consistent 'cooking bacon in a pan sizzling' sound is the ideal, if it is 'sputtering', that usually is a sign something is amiss, as can the smell (burning contaminates often 'taint' the smell and give you a clue something is amiss)

But most of it is 'practice, practice, practice'... until you start to get the feel for laying a good bead... (it helps considerably if you either have an experienced welder there while learning- either that or doing a class on welding (which is the same thing of course- an experienced welder) who can identify the issues as you are doing it so you can learn to identify them as you are doing it yourself...)

But think of it like learning to play a musical instrument- nobody picks up a saxaphone or sits down at a piano and is playing at 'concert level' within a minute or two...
 
And there is nothing finer and more satisfying than stepping back and admiring the workmanship of your colleagues boots welded to the bench by their steel toe caps.
May I draw you a list of volunteers
 
The one at the very top looks ok. The rest are a mixture of no gas on the left (Bird shi**y) the rest look like you didn't use enough current, but there are numerous problems with all of these. They should look like half moons and uniform down the weld. The above welds are normal for a beginner but have a look at some videos and make sure you keep your skin covered to stop radiation burns and a good mask otherwise you will get Arc Eyes, not nice feels like rubbing sand in your eyers. Try welding two pieces together (But weld) and see if you get good penetration, look at the other side, you will blow through and it will go wrong frequently but it takes practice, I have been welding for 40 years and it is a very big subject to learn and get right. Good luck.
 
I would have said 0.6 is too thin for welding 4mm. 0.8 would be better.
Having said that, it doesn't have a lot to do with the quality of your results.
I think you need more power.
Try experimenting with different power settings. Make sure you increase the wire feed speed to suit.
A good indicator is that when you stop the wire should still be projecting slightly from the shroud. Too short and your wire feed speed is too low. You risk the wire burning back to the guide tip. Sticking out more than maybe a mm or two and it's too fast.
Also play with the speed you move along the work.
And try a little more gas.
You will soon see a big improvement.
Dapop is spot on about cleanliness.
And I would agree you are better off to actually butt weld plates together, running a bead over the surface doesn't really tell you much.
As a beginner it helps to have both hands to control the torch. If you are using a hand held shield then get an auto darkening helmet. Not expensive nowadays but make life a lot easier.
 
More gas, more power.
Dial it up until you do blow through just to see what it's like, then wind it back. Learning is about trial and error and experiement.
And cleanliness never hurts. Give your metal a swipe over with a flapwheel or whatever first.
 
Where is the information required, type of MIG, current, feed speed etc etc. Half the battle is getting the right welder and setup correctly, then you are in a position to learn. Best thing to do is get an evening class in welding, it is how I was taught gas, MMA and TIG other wise it is like teaching yourself to drive and expecting to pass the test.
 
Can you suggest any good uk classes? Maybe around London? I want to learn, but I’m not sure where to begin
 
Take heart. Everybody who welds, from the guys in the shipyards to those who constructed the international space station, started where you are now.

Reddit is full of people who dont know their 4r5e from their elbow, but get off being critical of anyone on any subject.
Thanks man, the guys on this forum are lovely and have given proper advice so I’m looking up
 
Welding is a learned art- and takes lots of practice to learn lol
You have some porosity (usually an unclean surface, and/or gas flow is wrong (usually too low, but a extremely high gas rate can also cause it) and your 'heat'/penetration is too low on the ones on the right- current is too low

(I spent 3 months learning as a elec fitter apprentice how to weld, and that was 5 days a week, 8 hour days!!!)

Just welding a surface weld only teaches you so far- a better way is get some offcuts/scraps and weld them together, then break them apart again, to look at things like penetration etc

You actually have some 'reasonable' looking welds there as well so I suspect a lot is in your technique (with some pretty ugly ones as well but if this is your 'first time' nobody should expect perfection!!!)

I been welding on and off for over forty years, but even then I have to 'run a few practice beads' before doing any serious work if I haven't done it for a while, especially on a 'new machine'- as every single machine will do it slightly differently

So make sure that surface is CLEAN (and that includes things like oil from your hands even can cause that porosity- and even from earlier welds- clean before each new weld!!!) and experiment with your feed rate, amps, gas flow and the 'speed' of your torch travel... the best one is right at the top)


A lot of them look like the travel speed of the torch is too fast and/or too slow a wire speed (especially the 'chicken scratches' on the right) and those that are 'sitting on top' without good penetration- that can be too low on amps...

The sound will often give you clues as well while laying a weld- a consistent 'cooking bacon in a pan sizzling' sound is the ideal, if it is 'sputtering', that usually is a sign something is amiss, as can the smell (burning contaminates often 'taint' the smell and give you a clue something is amiss)

But most of it is 'practice, practice, practice'... until you start to get the feel for laying a good bead... (it helps considerably if you either have an experienced welder there while learning- either that or doing a class on welding (which is the same thing of course- an experienced welder) who can identify the issues as you are doing it so you can learn to identify them as you are doing it yourself...)

But think of it like learning to play a musical instrument- nobody picks up a saxaphone or sits down at a piano and is playing at 'concert level' within a minute or two...
Amazing advice. I will try again and update you guys. Thanks so much
 
If I were in your shoes I'd join the MIG welding UK forum and seek advice there, they are a very knowledgeable and friendly group and perhaps reach out to see if someone local to you could either give you some training or let you watch them doing some work - you'll learn very quickly that way and pick up all sorts of useful tips and advice.
Probs most will do it for a little beer money and you'll learn a lot quicker than poke and hope!!
 
If I were in your shoes I'd join the MIG welding UK forum and seek advice there, they are a very knowledgeable and friendly group and perhaps reach out to see if someone local to you could either give you some training or let you watch them doing some work - you'll learn very quickly that way and pick up all sorts of useful tips and advice.
Probs most will do it for a little beer money and you'll learn a lot quicker than poke and hope!!
Haha solid advice mate, will do that right now. God this place is a breath of fresh air from Reddit haha
 
Ooh, you've started something now! Ask 5 welders and you'll get 20 opinions of what's wrong. I've been welding 30 years (just hobby welding, car restoration, bike frames, bit of sculpture) but started with a couple of courses at tech college, not expensive but great for learning.
Having said that it looks like the token could do with a clean, bit more gas flow, bit more heat. Difficult to say without knowing your current setup though; wire feed/A, V, gas flow rate, type of wire, etc. Some good comments above.
 
Welding is what I term one of the "rough" arts. I work next to a good welder. I can weld OK using the gun/gas he's set up. But it's far from the trials of woodworking. Cut it a bit short? Just fill it with weld. Cut one a foot to short? Weld a bit on.etc. Once you can add to stuff mistakes are easy to put right. The material is also cheap and homogenous and in very long lengths (5m). The most strange is his bandsaw blades last longer than mine! (both m42).
Just keep trying and turn it up....
 
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