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malcolm
& Clementine the Cat
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No worries - I think the original thing was answered earlier on. If you are on here tomorrow night we might continue - for now I'm still a bit confused, but more importantly I'm hungry. Off to have a meal.
yes sorry, was beign too geenralist here...it was decomposition of a molecule but to break a molecule (or anything) you need energy and the result is also the release of energy as a covalence bond is broken (one of the O-C-O bond is broken..that's CO2)
If you try to break a red brick with a hammer, you'll inject energy into the brick. Chances are you'll hear a bang (that's energy in sound wave) and if you could monitor the temperature of the brick within the vicinity of the impact you'll find that it is slightly hotter..
You can use the same analogy with molecules / gas / atoms..except for the noise!!!!
domo arigato
Ralphy
If you try to break a red brick with a hammer, you'll inject energy into the brick. Chances are you'll hear a bang (that's energy in sound wave) and if you could monitor the temperature of the brick within the vicinity of the impact you'll find that it is slightly hotter..
You can use the same analogy with molecules / gas / atoms..except for the noise!!!!
domo arigato
Ralphy
ok..
I am going to have to dash too, the missus is starting to think i have lost it talking physics on the net..well i'd guess she'd knew by now!!!
Weldequip : i am interest in your gear. i need to see whether MIG for what i want to do is ok or i'll have to go for TIG, but so far you are top of my picking list
Malcolm / others, i am off until next monday, but if you want / have more question email me at ghislain.berthelot@tesco.net and i'll do my best to help.
"it's locked, it's loaded...LET'S OFFROAD"!!!
Ralphy
I am going to have to dash too, the missus is starting to think i have lost it talking physics on the net..well i'd guess she'd knew by now!!!
Weldequip : i am interest in your gear. i need to see whether MIG for what i want to do is ok or i'll have to go for TIG, but so far you are top of my picking list
Malcolm / others, i am off until next monday, but if you want / have more question email me at ghislain.berthelot@tesco.net and i'll do my best to help.
"it's locked, it's loaded...LET'S OFFROAD"!!!
Ralphy
Thanks Hugh that is something I`ve wondered about. So would we use that on heavy stuff like 10mm or thereabouts?
Alex
Zzzzzzz.....
Uh... no... sir... I was awake the whole time... I swear...
Wow, I never expected that so much science would be thrown into the mix!
I think from what I've heard here, I'll stick to c02/argon mix for the steel.
With 0.8mm wire.
Although, i love these posts... truly fascinating stuff!
Many thanks to you all!
Please, do keep adding your tu-pence!
Uh... no... sir... I was awake the whole time... I swear...
Wow, I never expected that so much science would be thrown into the mix!
I think from what I've heard here, I'll stick to c02/argon mix for the steel.
With 0.8mm wire.
Although, i love these posts... truly fascinating stuff!
Many thanks to you all!
Please, do keep adding your tu-pence!
HughF
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you can run .6mm wire all the way up to 150-160 amps but ONLY if your feed motor will feed fast enough to deliver the required current. Remember, wire speed = current control, voltage settings are exactly that, change the circuit voltage. Remember, mig uses a constant voltage or CV powersource so your open and closed circuit voltages are the same.
I use .6mm solely in my 160 amp mig on 1/4 plate as it means I only have 1 roll of wire to worry about.
I'd stick with argoshield light as well as you won't see much of a difference between that and universal or heavy on 3-5mm plate.
As for welding 10mm plate, personally I'd move away from mig for this thickness and use DC MMA with 7024 rods for downhand or a decent quality 7018 for positional.
H
I use .6mm solely in my 160 amp mig on 1/4 plate as it means I only have 1 roll of wire to worry about.
I'd stick with argoshield light as well as you won't see much of a difference between that and universal or heavy on 3-5mm plate.
As for welding 10mm plate, personally I'd move away from mig for this thickness and use DC MMA with 7024 rods for downhand or a decent quality 7018 for positional.
H
HughF
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Alex... I will write a decent description when I get home from work later today!
in the mean time: MMA and TIG use a constant current drooping voltage power source where the open circuit voltage is high (50 + volts) and the closed circuit voltage drops off.
Mig and flux core use a constant voltage power source where the current ramps up and down through the choke as the arc short circuits (in the case of dip transfer)
http://en.wikipedia.org/wiki/MIG_welding#Power_supply
H
in the mean time: MMA and TIG use a constant current drooping voltage power source where the open circuit voltage is high (50 + volts) and the closed circuit voltage drops off.
Mig and flux core use a constant voltage power source where the current ramps up and down through the choke as the arc short circuits (in the case of dip transfer)
http://en.wikipedia.org/wiki/MIG_welding#Power_supply
H
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Work the mag in there, some 1.2 wire and you'll fly round it. Uphill, down hill and round the corner
HughF
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Ah yes, nice heavy guage mig... we used to have old arc-tec 203's at work and my where they reliable, run on full chat on 1.2mm wire all day long!
I recommended mma as I thought alex had an old oxford lying around and tbh, he'll need a big industrial mig to get decent results on 10mm plate whereas mma seems to give better results per amp on the thicker stuff imho. Welded lots of downhand fillets on 12-15mm plate with 7024's from a 190 amp mma set in multiple pases with excellent results.
H
I recommended mma as I thought alex had an old oxford lying around and tbh, he'll need a big industrial mig to get decent results on 10mm plate whereas mma seems to give better results per amp on the thicker stuff imho. Welded lots of downhand fillets on 12-15mm plate with 7024's from a 190 amp mma set in multiple pases with excellent results.
H
HughF
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arc-tec were an old british firm I think. the 203's were 300 amp iirc but you could load them with .6 wire and go down to do 1mm plate with them as well!
We were a cnc sheet metal firm so used them from the thin right up to the thick stuff..
We were a cnc sheet metal firm so used them from the thin right up to the thick stuff..
Ralphy
Radon is certainly not Noble or Inert as we welders call it. Its radioactive !!!
http://www.hpa.org.uk/radiation/radon/index.htm
Carbon Oxide is usually called Carbon Monoxide
Steel "saturated" with Carbon is called Cast Iron
Are you taking the ...............
malcolm
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Radon is still a noble gas. All that means is that it doesn't really get involved in chemical reactions. The fact it's radioactive and will give you cancer if you try to weld with it is neither here nor there. That's a nuclear thing rather than a chemical thing.
True though that CO is carbon monoxide - it tends to form when there isn't enough oxygen around to make carbon dioxide (C02) or when something else has nicked the oxygen from it. It's even more easy to pinch oxygen from the next element along the line - Nitrogen - that's what makes Nitrous Oxide so much fun.
High carbon steel is normally used for castings, and it would be interesting to know the other forms.
Completely straying away from the topic once more - here's a fun poem about Schrodinger's next door neighbour's cat.
BTW - Welcome back Al.
True though that CO is carbon monoxide - it tends to form when there isn't enough oxygen around to make carbon dioxide (C02) or when something else has nicked the oxygen from it. It's even more easy to pinch oxygen from the next element along the line - Nitrogen - that's what makes Nitrous Oxide so much fun.
High carbon steel is normally used for castings, and it would be interesting to know the other forms.
Completely straying away from the topic once more - here's a fun poem about Schrodinger's next door neighbour's cat.
BTW - Welcome back Al.
Well I never. I was thinking that radioactive cannot be inert. I see what you mean but it still seems illogical. You live and learn. Where I live Radon is a big problem and costs a fortune to control. I daren't tell the guys in the pub that its inert.
Thanks for the welcome.
Carbon Monoxide is the "active" gas in MAG welding as opposed to MIG (inert gas) welding. The Carbon Dioxide dissociates due to the heat, forms Carbon Monoxide which wants to revert back to the Dioxide. To do so it picks up Oxygen from the weld, deoxidizes in other words. So it actively affects the weld metal.
You can get high carbon steel in all forms but many castings rely on high carbon for their strength as unlike plate they are often too big or too complicated to heat treat. When you get to saturation they become cast irons and its the free carbon that usually causes the problems as it acts like small defects.
Thanks for the welcome.
Carbon Monoxide is the "active" gas in MAG welding as opposed to MIG (inert gas) welding. The Carbon Dioxide dissociates due to the heat, forms Carbon Monoxide which wants to revert back to the Dioxide. To do so it picks up Oxygen from the weld, deoxidizes in other words. So it actively affects the weld metal.
You can get high carbon steel in all forms but many castings rely on high carbon for their strength as unlike plate they are often too big or too complicated to heat treat. When you get to saturation they become cast irons and its the free carbon that usually causes the problems as it acts like small defects.
malcolm
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The CO thing makes a lot of sense from an anti corrosion point of view. Sounds like the sort of thing you do with oxy welding by turning up the Acetylene. I still don't understand why they include 2% of oxygen in Argoshield Light.
I can certainly see the advantage in the active gas thing. Pure Argon is great at maintaining an arc but the weld ends up rubbish looking. Add a bit of CO2 and Oxygen and the welds become smooth and rounded just like some pro had done them.
The BOC page describes what the active components do but not how. I'd love to know what's going on there if you have any info.
I can certainly see the advantage in the active gas thing. Pure Argon is great at maintaining an arc but the weld ends up rubbish looking. Add a bit of CO2 and Oxygen and the welds become smooth and rounded just like some pro had done them.
The BOC page describes what the active components do but not how. I'd love to know what's going on there if you have any info.
