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have fun!cardiffrob
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Would anyone care to offer some 'guide settings' for a first attempt at zapping holes in steel and ali plate? Having only ever MIGged before and having only ever had one lesson, I'd be grateful for some guestimates for the amps/DCEN/DCEP/slope (shows how little I know!) etc settings. Obviously 150 amps on a 1.5mm steel plate is going to be wrong, but, any more specific pointers would be welcomed.
Wyn, I might need to pick your brains again in the near future!
Wyn, I might need to pick your brains again in the near future!
Starting with steel will make life a little easier. Ally isn't really more difficult, just different but when you contaminate a tungsten it tends to make a bigger mess when welding ally.
If you haven't already found it when reading the TIG section of this forum then download the Miller TIG resources articles. There's an amperage calculator on their site but it's not that accurate, especially for a beginner whose gonna be welding slower. Might be a touch high when starting, moreso with steel than with Al. Another rough ballpark for amperage is 1 amp per 0.001" again be on the high side while learning. Arc length and travel speed obviously influence amperage too. Small offcuts will make life harder especially with Al, say min of 6 x 3" for butt weld coupons
IIRC the Miller guides don't talk much if at all about slope settings as they assume a foot pedal (or hand remote) will be used. I'd start with some 2 or 3mm steel and just run some beads to begin with. Have a play with slope settings while you're running beads and you'll get a better feel for what's needed and what you like. Slope up not really important a lot of the time, start with 0.5 - 1sec maybe a touch more to slow things down initally. Slope out more benficial with regards to leaving craters, start at say 3secs and have a play. There'll be settings for starting/initial amperage and crater/finish current too. Sometimes these are independant, sometimes set as a %. I'd start with say 70 - 80% initial current and 50% crater current, again crater current more important of the two most of the time and have a play
When you end a weld keep the torch still while the post flow does it's thing. Primary role is to protect the tungsten as it cools so need longer flow times at higher amps and for ally as AC is harder on the tungsten. A rough rule of thumb for aircooled torches is 1 sec per 10A but you'll need a minimum of 4 or 5 secs. If the tungsten ends up discoloured and you haven't dipped it then turn the post flow up a touch.
Get a pack of tungstens and sharpen em all so you don't have to keep stopping to sharpen when you dip em. Once you see some consistancy with beads on plate move onto some joints, again preferably with steel. Once consistant with steel you'll find the switch to ally less frustrating as the muscle memory means you won't be welding the tungsten, filler and weldment into one lump as often
If you haven't already found it when reading the TIG section of this forum then download the Miller TIG resources articles. There's an amperage calculator on their site but it's not that accurate, especially for a beginner whose gonna be welding slower. Might be a touch high when starting, moreso with steel than with Al. Another rough ballpark for amperage is 1 amp per 0.001" again be on the high side while learning. Arc length and travel speed obviously influence amperage too. Small offcuts will make life harder especially with Al, say min of 6 x 3" for butt weld coupons
IIRC the Miller guides don't talk much if at all about slope settings as they assume a foot pedal (or hand remote) will be used. I'd start with some 2 or 3mm steel and just run some beads to begin with. Have a play with slope settings while you're running beads and you'll get a better feel for what's needed and what you like. Slope up not really important a lot of the time, start with 0.5 - 1sec maybe a touch more to slow things down initally. Slope out more benficial with regards to leaving craters, start at say 3secs and have a play. There'll be settings for starting/initial amperage and crater/finish current too. Sometimes these are independant, sometimes set as a %. I'd start with say 70 - 80% initial current and 50% crater current, again crater current more important of the two most of the time and have a play
When you end a weld keep the torch still while the post flow does it's thing. Primary role is to protect the tungsten as it cools so need longer flow times at higher amps and for ally as AC is harder on the tungsten. A rough rule of thumb for aircooled torches is 1 sec per 10A but you'll need a minimum of 4 or 5 secs. If the tungsten ends up discoloured and you haven't dipped it then turn the post flow up a touch.
Get a pack of tungstens and sharpen em all so you don't have to keep stopping to sharpen when you dip em. Once you see some consistancy with beads on plate move onto some joints, again preferably with steel. Once consistant with steel you'll find the switch to ally less frustrating as the muscle memory means you won't be welding the tungsten, filler and weldment into one lump as often
cardiffrob
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Thanks. I had an initial nightmare with a bit of St Elmo going on but I traced that to the line not being fully purged of air. I then went for some 1.3mm ali sheet and had a first go with my shiny new money-pit machine. The first go is from bottom to top at 40 amps, the first few dry and then with some 4000-series rod (can't recall which)
As Wyn will know, I have a knackered back from a slipped disc plus my left thumb was wrecked in a car accident, so feeding the rod and operating the trigger is more of a juggling act than usual.
I'm guessing that I could lower the 'cleaning' %age and maybe deepen the penetration a bit? How is it possible to make the weld taller? Do you just add rod faster?
PS. Pleeeeease ignore the burnt bit on No4 and the stuck end on number 6 where I got the last extra dip of the rod all wrong.
PPS Stainless wire brush on order!
As Wyn will know, I have a knackered back from a slipped disc plus my left thumb was wrecked in a car accident, so feeding the rod and operating the trigger is more of a juggling act than usual.
I'm guessing that I could lower the 'cleaning' %age and maybe deepen the penetration a bit? How is it possible to make the weld taller? Do you just add rod faster?
PS. Pleeeeease ignore the burnt bit on No4 and the stuck end on number 6 where I got the last extra dip of the rod all wrong.
PPS Stainless wire brush on order!
cardiffrob
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Thanks, Hotrodder. Minor brain fade here but that figure of 1A per 'thou means 25A per mm, right?
Next question is...do you regrind a tungsten every time you even suspect contamination or is it feasable to continue with a weld if the tip has been spattered? Does a wandering arc (or lack thereof) indicate whether there is contamination or is a visial check going to work?
Soooooo many questions!
Next question is...do you regrind a tungsten every time you even suspect contamination or is it feasable to continue with a weld if the tip has been spattered? Does a wandering arc (or lack thereof) indicate whether there is contamination or is a visial check going to work?
Soooooo many questions!
1mm = 0.040" near as damn it. Like the Miller calculator it's a starting ball point and will most likely be a bit on the high side, especially while learning. FWIW i typically weld (butt welds) 1.2mm Al at around 45-50A, 1.6mm @ 65-70A.
Typically i'm using a foot pedal with the machine set a bit higher so i don't have to hang around at the beginning (and when tacking) and/or speed up loads as the part heats up. If i'm grovelling around on the floor and using torch button would set the machine to around 85A for tacking 1.6mm and then turn it down. Note with small offcuts/parts the weldment gets heatsoaked very quickly making for larger changes in amperage or travel speed
When you tag a tungsten (touch down or stab the filler into the arc/tungsten) there's usually a small flash and the arc colour will change, usually more greenish but might vary with lens colour. Depends how badly the tungstens been tagged but typically the arc will become more diffuse and wander. Sometimes you get away with it. There'll be a telltale left on the weld in the form of some soot- blackish on Al like in your pic, brownish on steel
Quality of the tungsten tip is important. If the tip is ****** (cackhanded tungsten dressing or bits of weld metal stuck to it) then the arc will be ******/diffuse/unstable and welding will become harder to impossible. Don't try to keep going as it'll make for a more frustrating learning curve. You'll soon get very good at sharpening tungstens...
Edit couple of vids...
Steel pipe, wouldn't bother watching it all but there's multiple light touch downs. Note the brief flash as the arc is briefly extinguished. Can see a change of arc colour @ 6.55. Might have missed some bigger touchdowns as i scanned through it
How NOT to weld, filler gets stuffed into the arc right at the start- can hear the arc sound change, see the change in arc colour and the soot
Ally welding without touchdowns. Welders doing the fashionable 'big dimes' that the bike industry loves. They're fillets which obviously alters the amount of filler needed but you're better off adding less filler more frequently. Note the block used to steady his hand
Typically i'm using a foot pedal with the machine set a bit higher so i don't have to hang around at the beginning (and when tacking) and/or speed up loads as the part heats up. If i'm grovelling around on the floor and using torch button would set the machine to around 85A for tacking 1.6mm and then turn it down. Note with small offcuts/parts the weldment gets heatsoaked very quickly making for larger changes in amperage or travel speed
When you tag a tungsten (touch down or stab the filler into the arc/tungsten) there's usually a small flash and the arc colour will change, usually more greenish but might vary with lens colour. Depends how badly the tungstens been tagged but typically the arc will become more diffuse and wander. Sometimes you get away with it. There'll be a telltale left on the weld in the form of some soot- blackish on Al like in your pic, brownish on steel
Quality of the tungsten tip is important. If the tip is ****** (cackhanded tungsten dressing or bits of weld metal stuck to it) then the arc will be ******/diffuse/unstable and welding will become harder to impossible. Don't try to keep going as it'll make for a more frustrating learning curve. You'll soon get very good at sharpening tungstens...
Edit couple of vids...
Steel pipe, wouldn't bother watching it all but there's multiple light touch downs. Note the brief flash as the arc is briefly extinguished. Can see a change of arc colour @ 6.55. Might have missed some bigger touchdowns as i scanned through it
How NOT to weld, filler gets stuffed into the arc right at the start- can hear the arc sound change, see the change in arc colour and the soot
Ally welding without touchdowns. Welders doing the fashionable 'big dimes' that the bike industry loves. They're fillets which obviously alters the amount of filler needed but you're better off adding less filler more frequently. Note the block used to steady his hand
gavuk
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If you have back problems ,make sure you are comfortable ,far easier to be steady handed when sat down with arms planted on the bench ,and don't hold you breath,difficult to relax when suffocating 
......there are a few ways of holding the torch and feeding the wire ,try them all ...you tube search for tig welding ,there are gadgets to help with filler wire feeding never tried any personally, might help .....wire feed
......there are a few ways of holding the torch and feeding the wire ,try them all ...you tube search for tig welding ,there are gadgets to help with filler wire feeding never tried any personally, might help .....wire feedcardiffrob
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Right. I reduced the 'cleaning' %age to about 50% and upped the amps for the lower weld (60 amps indicated) and lowered to about 50 amps for the upper one. The other little nightmare was as a result of the old "forgot to turn the gas on again after lunch" trick which totally farqued the ceramic cup.
How fine does the tungsten finish need to be? I guess that ali will ball on AC quickly, though.
Thanks, Gav, for that link. Quiet handy but my thumb doesn't work well enough to use it. I have a few bits of stainless rod going spare right here!
(Yes, they go right through to the wrist bones!)
How fine does the tungsten finish need to be? I guess that ali will ball on AC quickly, though.
Thanks, Gav, for that link. Quiet handy but my thumb doesn't work well enough to use it. I have a few bits of stainless rod going spare right here!
(Yes, they go right through to the wrist bones!)
cardiffrob
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Another quick question.
If I use the organ pedal (correct terminology?) and set 50 amps normal and 70 amps pulse, what amps do I get at 0%, 50% and 100% of the pedal travel? I'm not sure I've got the correct understanding of what 'Pulse' actually does for me.
Sorry for all the posts and knumbskull questions.
If I use the organ pedal (correct terminology?) and set 50 amps normal and 70 amps pulse, what amps do I get at 0%, 50% and 100% of the pedal travel? I'm not sure I've got the correct understanding of what 'Pulse' actually does for me.
Sorry for all the posts and knumbskull questions.
Bloody hell! I get the urge to play with new toys but, erm... Doing well to even hold a stick of filler
It's not that the tungsten needs to have a polished finish or anything, as you say it'll will round off with AC. With the balance setting you're using it'll likely ball up properly. Inverter machines tend to ball tungstens less than transformer machines (although settings play a big part) and so if the tips wonky can end up staying wonky as the tip rounds off.
Whoooah, slow down. Turn the pulse off and stop trying to run before you can crawl. All pulse will do for now is add a bunch of extra variables to confuse you. If you're determined to dive straight in with the pedal on aluminium then just concentrate on running some consistant weld beads- even size, even penetration, consistant arc length and no craters at the ends
Pedal will probably be linear i.e. 50% pedal will be halfway between the machines min and main amperage settings. Can usually test it by moving the pedal and watching the panel readout but it doesn't really matter i.e. the numbers don't matter, like a car throttle pedal it's one of those things that'll become instinctive with time and you just set it a little higher than needed and make small adjustments based on the weldpool. One of the reasons i suggested starting with steel as generally don't need to make as many changes to pedal or travel speed so one less thing to think about while you get used to reading the weldpool. I assumed you were using a torch button as a pedal overrides slope settings i.e. all controlled by your foot
It's not that the tungsten needs to have a polished finish or anything, as you say it'll will round off with AC. With the balance setting you're using it'll likely ball up properly. Inverter machines tend to ball tungstens less than transformer machines (although settings play a big part) and so if the tips wonky can end up staying wonky as the tip rounds off.
Whoooah, slow down. Turn the pulse off and stop trying to run before you can crawl. All pulse will do for now is add a bunch of extra variables to confuse you. If you're determined to dive straight in with the pedal on aluminium then just concentrate on running some consistant weld beads- even size, even penetration, consistant arc length and no craters at the ends
Pedal will probably be linear i.e. 50% pedal will be halfway between the machines min and main amperage settings. Can usually test it by moving the pedal and watching the panel readout but it doesn't really matter i.e. the numbers don't matter, like a car throttle pedal it's one of those things that'll become instinctive with time and you just set it a little higher than needed and make small adjustments based on the weldpool. One of the reasons i suggested starting with steel as generally don't need to make as many changes to pedal or travel speed so one less thing to think about while you get used to reading the weldpool. I assumed you were using a torch button as a pedal overrides slope settings i.e. all controlled by your foot
cardiffrob
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Right-o. I've not used this 'pulse' feature yet as it is down at zero. As you say, I'll leave it until I can weld ali straight and have gained a better understanding of the basics.
I was concerned a bit by the fact that the dial shows circa 20 amps momentarily after I switch off before it goes back up to the selected amperage.
I tried the torch trigger first to reduce the number of items to concentrate on but my lask of grip with both hands means that the pedal will need to become a regular feature of my welding. The trigger itself is in a cr4ppy position for me to use since I'm holding the neck of the torch from below (thumb underneath) rather than like a pistol pointing downwards. Oh, and the thumb wires have come out since that picture but the nerves are gone and the range of movement is poor. Not good for welding and also not good for operating the autothrottle controls on the Boeing 757 I drive at work.
Good point on the steel being easier to learn on but I've only got ali to work on in the future so I might as well go in at the deeeeeep end.
I was concerned a bit by the fact that the dial shows circa 20 amps momentarily after I switch off before it goes back up to the selected amperage.I tried the torch trigger first to reduce the number of items to concentrate on but my lask of grip with both hands means that the pedal will need to become a regular feature of my welding. The trigger itself is in a cr4ppy position for me to use since I'm holding the neck of the torch from below (thumb underneath) rather than like a pistol pointing downwards. Oh, and the thumb wires have come out since that picture but the nerves are gone and the range of movement is poor. Not good for welding and also not good for operating the autothrottle controls on the Boeing 757 I drive at work.
Good point on the steel being easier to learn on but I've only got ali to work on in the future so I might as well go in at the deeeeeep end.
cardiffrob
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From those pics, would I get fatter 'pennies' from a larger rod or are they indicative of me going too slowly and remelting each penny during the subsequent weld?
Shox Dr
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off topic but worth saying
Rob, a friend of mine crushed a hand a few years ago, had to have all his fingers inc thumb pinned. The Doc said he would be lucking if he got any moment after the pins were to be removed in 6weeks; How wrong they were.
He was advised to exercise with a light rubber band, spread over his finger ends, and to slowly stretch, working up to stronger bands as his strength recovers. When ever you saw him he had a laggy band in his hand, within 6 months you would had never known what had happened, full articulation and strength back.
Speak to your physio and see what they say.
Rob, a friend of mine crushed a hand a few years ago, had to have all his fingers inc thumb pinned. The Doc said he would be lucking if he got any moment after the pins were to be removed in 6weeks; How wrong they were.
He was advised to exercise with a light rubber band, spread over his finger ends, and to slowly stretch, working up to stronger bands as his strength recovers. When ever you saw him he had a laggy band in his hand, within 6 months you would had never known what had happened, full articulation and strength back.
Speak to your physio and see what they say.
cardiffrob
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It all happened a few years ago so there won't be any change in the future. My hand did, however, show some improvement shortly after I opened the envelope containing the insurance cheque for just under £100,000
The CAA are happy to let me keep my licence so long as I stay in the appropriate seat since I can't grip the control column with my left hand.
Progress this morning. I burnt the edges off of several 90 degree joints and had one run of about an inch that didn't look embarrasing. I then changed to a 2.4mm red electrode and had another crack at mild steel. Much nicer and it seems more controllable (as previously suggested) so I might stay in DC land for a while to get my pedal action co-ordinated.
Gas is down from 210 to 180 already. Glad I didn't get the smaller size bottle!
2 ceramic cups ruined, 15 1.6mm ali rods melted, 1 inch of joint welded and about £1000 down.
The CAA are happy to let me keep my licence so long as I stay in the appropriate seat since I can't grip the control column with my left hand.
Progress this morning. I burnt the edges off of several 90 degree joints and had one run of about an inch that didn't look embarrasing. I then changed to a 2.4mm red electrode and had another crack at mild steel. Much nicer and it seems more controllable (as previously suggested) so I might stay in DC land for a while to get my pedal action co-ordinated.
Gas is down from 210 to 180 already. Glad I didn't get the smaller size bottle!
2 ceramic cups ruined, 15 1.6mm ali rods melted, 1 inch of joint welded and about £1000 down.
cardiffrob
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Just had my first go at welding without filler (homogenous welding, or summat like that) on steel. 2.4 thoriated, 60 amps, DC with 1.3mm steel sheet.
Hard to get a scale on it but the scratch in the centre is about 3mm long. Very tight bead compared to MIG!
Hard to get a scale on it but the scratch in the centre is about 3mm long. Very tight bead compared to MIG!
cardiffrob
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Another try at scaling the pic.
Question. Why is it so much harder to do THIS with ali? I seem to get a lot more holes and misfires with ali and need filler.
PS The nice top edge is where I cut off the nasty bit where I forgot to go "DC" after a short ali session. Doh!
PPS Obviously I've run over this with Scotchbrite to get the blue off of it.
Question. Why is it so much harder to do THIS with ali? I seem to get a lot more holes and misfires with ali and need filler.
PS The nice top edge is where I cut off the nasty bit where I forgot to go "DC" after a short ali session. Doh!
PPS Obviously I've run over this with Scotchbrite to get the blue off of it.
