- Thread starter Cris B
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What you need to understand is that more weld DOES NOT make a stronger weld, penetration and fusion is the key.
Looking at that first pic again you can see that even on this steel such as that, most of the weld is just sat on it, not penetrated into it.
I'm suspecting you may be holding the torch a bit too far away, ideally there should be no more than say a 10mm gap between the contact tip and the workpiece, this is known as 'stickout' and is just that, the amount of wire sticking out from the tip.
Thanks for posting the pic though, gave a few of us a chuckle and thanks for taking the criticism in good spirits too.
I did wonder if you were making a camouflaged nesting box for a pigeon loft!
Looking at that first pic again you can see that even on this steel such as that, most of the weld is just sat on it, not penetrated into it.
I'm suspecting you may be holding the torch a bit too far away, ideally there should be no more than say a 10mm gap between the contact tip and the workpiece, this is known as 'stickout' and is just that, the amount of wire sticking out from the tip.
Thanks for posting the pic though, gave a few of us a chuckle and thanks for taking the criticism in good spirits too.
I did wonder if you were making a camouflaged nesting box for a pigeon loft!
gavuk
artful-bodger
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I did wonder if you were making a camouflaged nesting box for a pigeon loft!
Ha ha
......Chris well done mate ,but your not making it easy for yourself,,,,get some 2mm or thicker steel and practice running beads ,for car stuff,you will need to be careful about introducing too much heat as it will not only blow through but will also cause distortion,if you only have the sheet steel to practice on then look at "the thin metal technique"..here thin metal....you will get a "feel" for when the weld will blow through.....Done properly you will get good penetration and it will be a lot quicker to learn ,with car panels its best not to lay more than an inch of weld before allowing it to cool down to minimize distortion,so the thin metal technique is ideal You did get an auto shield? get your head in close but to one side of the shield so you can see the weld ,use both hands ,ideally resting your hand arm so you are comfortable,and don't forget to breathe normally .....keep going Chris you`ll get it bud...
not sure how your holding the torch but i find it easiest to hold the torch just behind the shroud between my forefinger and indexfinger nd use my fingers to control the movement of the tip while my other hand pulls the trigger and supports the torch.. unless its a LONG run (which on car work isn`t wise) all of the movement can be controlled smoovly and accuratly through your wrist..
hope that makes sense and doesn`t sound pornographic!!
with that outside corner was it done by pulsing the torch? or pull the triiger and dont stop until you run out of metal??
not sure how your holding the torch but i find it easiest to hold the torch just behind the shroud between my forefinger and indexfinger nd use my fingers to control the movement of the tip while my other hand pulls the trigger and supports the torch.. unless its a LONG run (which on car work isn`t wise) all of the movement can be controlled smoovly and accuratly through your wrist..
hope that makes sense and doesn`t sound pornographic!!
with that outside corner was it done by pulsing the torch? or pull the triiger and dont stop until you run out of metal??
Cris B
Every day welding is a school day
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I'm am all for the comments and I will get the technique eventually 
Also since my stag do I have a whole new persepctive on public humiliation LOL.
Many of you have suggested that I should start on thicker steel and I know I am making it difficult for myself by working on the thin stuff but pretty much all of the welding I am going to be doingwill be on metal SWG20 so I don't see the advantage in learning on thicker stuff - I will still have to master the thin stuff to do what I need to do!
Clearly yesterdays approach was completely the wrong way to go about it, so I went back to welding the way I had been practicing to start with. So had another crack at the box today - here is mark 2!
This was 15lpm gas and there were a couple bubbly welds. The technique was also a little off and on, but not in a good way. I was aiming to do about 3cm of weld then stop, do a different section and come back to it. So I will try mark 3 on 20lpm again and go a little slower as the penetration was okay, but could be better. Sorry, I forgot to take a picture of the inside!
I may fiddle with my Speedglas mask too as I am struggling to see the join line to follow with the weld pool as the mask is auto darkening too much to keep on track. I think this was my biggest problem today.
Also since my stag do I have a whole new persepctive on public humiliation LOL.Many of you have suggested that I should start on thicker steel and I know I am making it difficult for myself by working on the thin stuff but pretty much all of the welding I am going to be doingwill be on metal SWG20 so I don't see the advantage in learning on thicker stuff - I will still have to master the thin stuff to do what I need to do!
Clearly yesterdays approach was completely the wrong way to go about it, so I went back to welding the way I had been practicing to start with. So had another crack at the box today - here is mark 2!
This was 15lpm gas and there were a couple bubbly welds. The technique was also a little off and on, but not in a good way. I was aiming to do about 3cm of weld then stop, do a different section and come back to it. So I will try mark 3 on 20lpm again and go a little slower as the penetration was okay, but could be better. Sorry, I forgot to take a picture of the inside!
I may fiddle with my Speedglas mask too as I am struggling to see the join line to follow with the weld pool as the mask is auto darkening too much to keep on track. I think this was my biggest problem today.
dunno what shade your on but my miller screen is set to 9 for pretty much everything except ally MIG....
imo theres still too much wire... do you feel the torch pushing back at all as you weld?? like the wire is hitting the metal and pushing against you rather than melting???
as for the mocking, please don`t take offence i personally dont mean anything by it.. just a bit of banter...
next time you have 2 pieces joined corner to corner maybe try a few manly tacks along its length with a 10mm gap between them and get some pics of that?? a stationary burst of 1 or 2 seconds should be ample and give a nice spot without too much weld build up on the topside and penatration on the inside and of course without blowing a ruddy gurt hole in it...
imo theres still too much wire... do you feel the torch pushing back at all as you weld?? like the wire is hitting the metal and pushing against you rather than melting???
as for the mocking, please don`t take offence i personally dont mean anything by it.. just a bit of banter...
next time you have 2 pieces joined corner to corner maybe try a few manly tacks along its length with a 10mm gap between them and get some pics of that?? a stationary burst of 1 or 2 seconds should be ample and give a nice spot without too much weld build up on the topside and penatration on the inside and of course without blowing a ruddy gurt hole in it...
Cris B
Every day welding is a school day
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No offence taken
I hadn't noticed the wire speed being too high, but I will try reducing it.
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20 lpm is way too high and will pretty much double your gas consumption £££££!!! You won't need any more than 10 or 12 if welding indoors, if you're still struggling with gas coverage then it's your technique (or your regulator gauge) that is wrong. 
Angle of dangle is a big consideration, many learners tend to cant the torch over too far which messes up the gas coverage. You should be slightly off vertical and pushing the torch away from the weld, not pulling it for thin stuff.
We'll get you there, it may take us some time but we'll get you there!
Angle of dangle is a big consideration, many learners tend to cant the torch over too far which messes up the gas coverage. You should be slightly off vertical and pushing the torch away from the weld, not pulling it for thin stuff.
We'll get you there, it may take us some time but we'll get you there!
Cris B
Every day welding is a school day
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Yes 20lpm was high but I was just experimenting. I dropped it back down to 10lpm today and reduced the wire speed to 3 from 3.5. The power is stil set to 2.
Worked on my position with the torch and how close I was to be able to see the welds today which helped. I also spent time re-reading the thin metal technique today and putting it into practice on both the edge and butt welds.
Reverse
Edge welds improved towards the end of this attempt
Reverse
Butt Weld Practice
Joined all the bits together
Penetration was better when I managed to get the speed right. I think it will come with more practice.
Worked on my position with the torch and how close I was to be able to see the welds today which helped. I also spent time re-reading the thin metal technique today and putting it into practice on both the edge and butt welds.
Reverse
Edge welds improved towards the end of this attempt
Reverse
Butt Weld Practice
Joined all the bits together
Penetration was better when I managed to get the speed right. I think it will come with more practice.
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Getting better but still plenty of room for improvement.
I'm wondering if your gauge isn't reading accurately as you're still getting inadequate gas coverage by the look of it. How far are you holding the torch tip from the workpiece and how near to vertical are you holding it?
I'm wondering if your gauge isn't reading accurately as you're still getting inadequate gas coverage by the look of it. How far are you holding the torch tip from the workpiece and how near to vertical are you holding it?
Cris B
Every day welding is a school day
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Always rooms for improvement 
Holding the tip about 1cm from the work and at about 60 degrees from the vertical (well trying to anyway). The welds are worse when I've let the tip stray too far away from the metal. To be honest I still think I am moving too quickly and need to slow down so I will focus on improving those things tomorrow.
Holding the tip about 1cm from the work and at about 60 degrees from the vertical (well trying to anyway). The welds are worse when I've let the tip stray too far away from the metal. To be honest I still think I am moving too quickly and need to slow down so I will focus on improving those things tomorrow.
malcolm
& Clementine the Cat
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WTM MIG welder to help improve the tutorials. Must have GSOH and like frogs.
I reckon for thin stuff that distance torch to work is almost too much. The contact tip is recessed so I'd go a lot closer, occasionally touching the shroud to the work.
The angle is good for thin stuff, but you do need the torch very close - that allows you to reduce wire speed (all other things being equal).
I reckon for thin stuff that distance torch to work is almost too much. The contact tip is recessed so I'd go a lot closer, occasionally touching the shroud to the work.
The angle is good for thin stuff, but you do need the torch very close - that allows you to reduce wire speed (all other things being equal).
malcolm
& Clementine the Cat
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Yeah I started off with it dead close, but then you can't see what you're doing
Well move your head then!
Edit> should probably add more detail - you can't see what's happening from behind the torch, you need to position yourself so you can look from the side.
hello hello hello... things are looking better in them last pics... especially the butt weld...
by the looks of it your adopting a BOLB-pause-move-BOLB-pause-move method???
you mention not being able to see the weld when the shroud is close?? get round to the side of the torch and don`t be affraid to get your head near the weld, your not doing meters of weld and your not running MEGA amps so you won`t melt your face.. might break a sweat though!! hahaha
by the looks of it your adopting a BOLB-pause-move-BOLB-pause-move method???
you mention not being able to see the weld when the shroud is close?? get round to the side of the torch and don`t be affraid to get your head near the weld, your not doing meters of weld and your not running MEGA amps so you won`t melt your face.. might break a sweat though!! hahaha
Hi Chris B, In a lot of the pics you posted it seems to me that you are getting porosity or contamination either through lack of gas coverage or gas contamination or something else. (those little blow holes and bumps that appear on and in your welds, which are probably hollow).
So a couple of questions for you to check, are all your gas host connections tight and not leaking anywhere? You shouldn't have to use more than 10-12lt per minute of gas indoors. I can run my large 400amp Tweco #4 torch on that amount. Is your wire tension adjusted properly? when you welding, does your wire melt out smoothly or is it a stop start stop start type of weld arc? Does the wire push away intermittently while welding. To me it looks like you have a few small sections of "better" beading and then it goes to s..t. Are you also maintaining a constant distance for the work with your torch head? Lastly is your shroud head clean of splatter?
Regarding the "learning on thin metal as that is what you will be doing", I personally would try using 3mm-4mm steel first just to rule out if there is a problem with your machine or setup. If you can weld the thicker stuff then that would rule out a lot of machine errors or problems. If you can get a good weld on thicker stuff then it is a problem with your technique or your MIG settings on the thin stuff.
Thin stuff is reasonably hard to weld "properly" at the best of times unless your settings are spot on and you have the skill to do it, so it will be harder to work out if it is something you are doing wrong, or if your settings need to be adjusted or a combination of both. That doesn't mean putting enough wire blobs to cover everything, grinding it down, filling up the gaps till it looks filled. That sort of technique may cover the join but may not have fused the weld to the base metal. That's akin to joining panels together with putty/bog, it may look seamless but has no structural strength. As you are repairing a car, I would hate to be driving down the highway at 100 Km/hour and hit a pothole and have the motor or the floor go in a different direction to the rest of the car.
I don't intend to be condescending or anything but my advice would be to practice on some thicker metal first and when you learn how to get a good continuous bead on the thicker stuff, then in my opinion it will be much easier for you to scale down to the thinner stuff, 'cause the technique will be similar and you will only have to work out the settings that will work on your particular MIG. If you can't get good beads on the thicker stuff then you definitely won't get them on thin stuff and it will be harder to work out the cause. Just my 2 cents worth!
So a couple of questions for you to check, are all your gas host connections tight and not leaking anywhere? You shouldn't have to use more than 10-12lt per minute of gas indoors. I can run my large 400amp Tweco #4 torch on that amount. Is your wire tension adjusted properly? when you welding, does your wire melt out smoothly or is it a stop start stop start type of weld arc? Does the wire push away intermittently while welding. To me it looks like you have a few small sections of "better" beading and then it goes to s..t. Are you also maintaining a constant distance for the work with your torch head? Lastly is your shroud head clean of splatter?
Regarding the "learning on thin metal as that is what you will be doing", I personally would try using 3mm-4mm steel first just to rule out if there is a problem with your machine or setup. If you can weld the thicker stuff then that would rule out a lot of machine errors or problems. If you can get a good weld on thicker stuff then it is a problem with your technique or your MIG settings on the thin stuff.
Thin stuff is reasonably hard to weld "properly" at the best of times unless your settings are spot on and you have the skill to do it, so it will be harder to work out if it is something you are doing wrong, or if your settings need to be adjusted or a combination of both. That doesn't mean putting enough wire blobs to cover everything, grinding it down, filling up the gaps till it looks filled. That sort of technique may cover the join but may not have fused the weld to the base metal. That's akin to joining panels together with putty/bog, it may look seamless but has no structural strength. As you are repairing a car, I would hate to be driving down the highway at 100 Km/hour and hit a pothole and have the motor or the floor go in a different direction to the rest of the car.
I don't intend to be condescending or anything but my advice would be to practice on some thicker metal first and when you learn how to get a good continuous bead on the thicker stuff, then in my opinion it will be much easier for you to scale down to the thinner stuff, 'cause the technique will be similar and you will only have to work out the settings that will work on your particular MIG. If you can't get good beads on the thicker stuff then you definitely won't get them on thin stuff and it will be harder to work out the cause. Just my 2 cents worth!
Cris B
Every day welding is a school day
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More butt welding practice. Last weld was the one on the left. Very happy with it
Front
Reverse - the penetration on my best effort is only poor where it goes over the tack welds I did. Note to self, I must do better tack welds
Some more edge welding practice. Getting much better penetration now. The blobby bits are where I went over the tack welds which were a bit big.
Reverse
I started a thread for my project - which all of this building up and working towards yesterday.
Front
Reverse - the penetration on my best effort is only poor where it goes over the tack welds I did. Note to self, I must do better tack welds
Some more edge welding practice. Getting much better penetration now. The blobby bits are where I went over the tack welds which were a bit big.
Reverse
I started a thread for my project - which all of this building up and working towards yesterday.
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Not sure why you're weaving so much Cris, there's no need to and it's making your welds 3 times the width they should be so wire/gas/leccy/time all being wasted.
On a thin metal butt weld you want it as small as possible (but with adequate penetration of course) as you'll most likely be grinding it down afterwards.
On a thin metal butt weld you want it as small as possible (but with adequate penetration of course) as you'll most likely be grinding it down afterwards.
