No 'sizzle' at high amps?

[harryb94]

When I'm using my portamig up near the top end of its power I can't seem to get any form of sizzle or crackle like I get at lower power, it just tends to hum. I've tried playing around with different wire speeds but if I go up much more I start getting a molten spray coming off and much lower and it produces a poor weld.
I can produce a weld that looks decent but I realise that doesn't always means it's a good weld. Afraid I don't have any pictures of the welds which doesn't help much I realise but does this sound normal or is something obviously wrong?

 

[gordon stephenson]

Sounds like spray transfer

 

[visor_down]

Yep my portamig does exactly as you describe too .

 

[chevy2]

It happens when you weld at high amps and thin wire, if you were to go up one size on the wire and then weld again at the same amps the crackle you're getting at low power will return.

 

[harryb94]

Cheers guys, I'm not doing anything horrifically wrong then! I'm using 0.8 wire at the moment up to 215 amps (very occasionally) is there any problem with be using this over 1mm wire?

 

[chevy2]

Should be fine, if you find its constantly burning back to the tip even when upping the wire speed then you really need to go up a size on the wire.

 

[Richard.]

Gordon has is. Your going into spray transfer. The high voltage you've put on the wire has spread the arc wide and the name spray is exactly what it looks like. Globular transfer is large wire droplets forming as your welding and dip transfer is Low voltage to the wire feed ratio which gives the sizzling you hear and a very short arc length.

 

[Kent]

Bigger single phase plants will go into spray in 0.8mm at the end of their range you just cant give them enough wire. If you don't want spray transfer go up to 1mm some will still spray until you get the wire pretty much up there though

 

[awemawson]

So does Spray Transfer imply a good or a bad weld in terms of penetration and appearance ?

 

[Kent]

So does Spray Transfer imply a good or a bad weld in terms of penetration and appearance ?

Increases heat (not always good) and increases penetration. More prone to lack of shielding effect in wind and low flow rates. Nice smooth bead! you should actually see the arc ripping down into the parent metal and the wire filling it just behind (uses up a lot more electric at the meter)

 

[Richard.]

Increases heat (not always good) and increases penetration. More prone to lack of shielding effect in wind and low flow rates. Nice smooth bead! you should actually see the arc ripping down into the parent metal and the wire filling it just behind (uses up a lot more electric at the meter)

Wire feed increases penetration not heat (voltage). This widens the arc and gives bead spread.

 

[Kent]

Wire feed increases penetration not heat (voltage). This widens the arc and gives bead spread.

Spray arc dives deeper of that I can only say from pure doing it experience. As regards heat I wasn't meaning it increases anything other than itself (spray ups distortion because of the heat and its only of extra use on plug welds "spots" as some term them on sheet). There is so much more terminology used these days all I was ever told was " mig it normal" or "spray them" and am very happy to stay that way.

 

[mud90mike]

That's interesting to know, I have been playing with my portamig 285 and had exactly this when welding 12mm plate using .8, looks like a lovely flat weld but not your usual sound, I will swap the wire over and give it a try.

This is exactly why I spend so much time reading everything on here!

 

[Richard.]

Spray arc dives deeper of that I can only say from pure doing it experience. As regards heat I wasn't meaning it increases anything other than itself (spray ups distortion because of the heat and its only of extra use on plug welds "spots" as some term them on sheet). There is so much more terminology used these days all I was ever told was " mig it normal" or "spray them" and am very happy to stay that way.

No need to suggest changing the way you do things mate not my intentions at all as your fabs I've seen look wonderful. I said the wire speed increases penetration and not the voltage just so that the op does Not start cranking up the voltage thinking he's going to penetrate deeper into the parent material because he won't unless he turns up the wfs. Yes turning up the voltage will increase distortion there is no doubt there because your increasing heat input and the best way to reduce heat input is to increase your wirefeed along with it to ensure good penetration and pick up the travel speed so the heat is not localised.

 

[Kent]

No need to suggest changing the way you do things mate not my intentions at all as your fabs I've seen look wonderful. I said the wire speed increases penetration and not the voltage just so that the op does Not start cranking up the voltage thinking he's going to penetrate deeper into the parent material because he won't unless he turns up the wfs. Yes turning up the voltage will increase distortion there is no doubt there because your increasing heat input and the best way to reduce heat input is to increase your wirefeed along with it to ensure good penetration and pick up the travel speed so the heat is not localised.

You know when I went to college they told us to learn MIG back at work- As they didn't have but a one! Just illustrates why guys struggle so much with stick now. I have a mate in his early thirties now and he stick welds at work (maintenance at heavy plant ) yet only got MIG at college Its useful listening to what you say Richard then I can tell people why I do stuff that I cant actually explain in words.

 

[BoatBuilderDave]

Spray will give you a very fluid puddle. I think it's only recommended for flat or horizontal. Vertical or overhead is a no-no. But I read that in a book, I only play welder at the weekends.

 

[Richard.]

Spray will give you a very fluid puddle. I think it's only recommended for flat or horizontal. Vertical or overhead is a no-no. But I read that in a book, I only play welder at the weekends.

That's right with solid wire Dip transfer for out of pos. Some fc wires will weld in spray transfer out of position.

 

[Kent]

I should ever try spray arc positional you need the control of a short tight arc (which it doesn't have)

 

[matt1978]

You can weld in Spray in the overhead position, for T-Fillets and Lap joints. One main point which I have not seen mentioned yet is that the material thickness will usually determine whether to weld in Dip or Spray.

You increase your voltage and therefore your wirespeed (which is effectively your current/amps) as the material your welding gets thicker. Spray is usually virtually a spatter free mode as the wire burns off without making contact with the weld pool, dip transfer on the other hand the wire touches the weld pool and "short circuits" many times a second. This is what causes the difference in the noise you can hear.

The various wire diameters all have differing voltage ranges at where they will be in dip/mixed/spray mode. So the voltage required for spray in a 0.8mm wire would only be dip in a 1.2mm as an example.

 

[Woody.v8]

I use spray transfer on thicker sections OV, But the conditions have to be right or most of it will end up down your neck