Me again, more odd behaviour :(

  1. Davek0974

    Davek0974 Arse!, Drink!, Girls!

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    Can do it, seems odd though as i would think the lights and CNC stuff would be going mental. I'll do some checks though, I know the workshop panel is ok as i was in there last week and tweaked all the clamps as a matter of course. I'll check the house end joints.

    It does seem to do it more if i don't use it much - been used pretty much every day these last few weeks and not done it at all. That makes me think of a gas leak maybe??

    The line to the welder seems tight as it will hold pressure for weeks, maybe line from unit to tip??
     
  2. carbon

    carbon Member

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    I had a call from a customer a few weeks ago that there machine had stopped working not a a welder but high current requirement with a 16 plug fitted. I couldn’t detect any power at the socket so removed the front cover after isolating the supply. I found one wire completely disconnected from the back of the socket and the other loose and no signs of arcing on these connections. So definitely work checking socket connections and if possible voltage and current at the socket when under load
     
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  3. davidjohnperry a different breed

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    I just saw the videos looks like your changing your arc length so the voltage will change depending how far or close you go but not from 19 v to 26 v if your using the correct size tip for the wire it only takes a micro scopic spatter to clog a tip try taking it out of s mig and try welding on a fixed setting could have a bad batch of wire or should I say a badly wound reel of wire if Ur running off a 13 amp plug you won't be running that power for a long duty cycle as they probably need 16 amp plugs but really if your sure it's not the machine it is either the op the power or the wire try uppjng to the next size tip it's a bit hill Billy but if it's your tip with micro spatter it might eliminate the issue
     
  4. Richard.

    Richard. Forum Supporter

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    Voltage won’t change with stickout. It’s a constant voltage process. Current goes up and down with stick out changes. Arc length remains the same all the time.
     
  5. davidjohnperry a different breed

    Messages:
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    yate/bristol
    Right I c @Richard. I thought this smart MIG stuff adjusted voltage if the arc length changed to suit the difference in arc length
     
  6. Munkul

    Munkul Member

    Messages:
    2,114
    Cumbria, UK
    When you have a problem with wire feed (essentially your changeable current level that's supposed to be roughly constant when welding with a consistent feed speed and stickout) your on-load voltage from the inverter will spike with a drop in current as the arc length changes drastically. The voltage spike will only be momentary but might still register on the display.
    Not sure how much of a spike this is - it's a bit of a spike with a transformer, I have a feeling it might be more of a spike with an inverter with whatever capacitor reserves are built up - but it definitely will vary from machine to machine. Some top-end machine's feedback systems are so fast that the spike will be tiny. Others will not be so, even decent units like the Rebel - they simply don't need the feedback to be so fast, because they don't have pulse. That's my understanding, anyway.

    As said by everyone else, my money is on a wire feed issue - whether it be torch or machine, not sure. Could be worth running a whole load of wire through it without an arc just to make sure the feeder is consistent.

    This is why you should always buy a welder from a decent bricks-and-mortar welding shop - so you can take it back to them and replicate the issue, and get THEM to sort it :) You can buy everything else online, but not the welder itself!
     
  7. Richard.

    Richard. Forum Supporter

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    On a constant current process like tig or MMA both the arc voltage and arc length can change with in and out variations. On mag (cv) these two things are fixed and only the current drawn will change. You have to physically change the arc voltage to change the arc length
     
  8. 8ob

    8ob Forum Supporter

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    moscow on thames
    Not saying it’s related but I had a problem not unsimilar to this and it was a badly wound mig reel, some of the wire had dropped down the side of the reel and some was overlaid. It was playing havoc with the wire feed, tried removing a load of it but gave up and binned it in the end.


    Bob
     
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  9. Davek0974

    Davek0974 Arse!, Drink!, Girls!

    Messages:
    919
    Location:
    Hertfordshire
    Thanks all.

    I have checked all the connections from house to welder now, no faults found.

    Please bear in mind that this is an extremely intermittent or random event, i have not had it for at least three weeks now.

    The welder WAS purchased from a reputable supplier but as the fault spans TWO different machines by two different makers and at two different quality levels, its clearly not the machine.

    I will attempt to make notes of voltage etc when or if it happens again, it *might* be wire feed being set too light, but can anyone explain how insufficient wire feed or slipping wire feed can cause a flare-up? I always thought low feed gave a crap weld and a pop-pop-pop sound as the arc struck and failed repeatedly - the effect i see is a blinding white flare like burning magnesium ribbon was at school ;)
     
  10. Davek0974

    Davek0974 Arse!, Drink!, Girls!

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    LOL - We can't say c r a p in a post - it changed it to jabberwocky :)
     
  11. Munkul

    Munkul Member

    Messages:
    2,114
    Cumbria, UK
    I didn't say quality supplier, I said "bricks and mortar" - a shop ;)

    It depends if you're in synergic smart-mig or manual.

    Manual - the voltage stays the same, and behaves like a normal mig - including the slow popping at low feeds/voltages.
    Synergic smart mig - it's trying to feed a certain feedrate but the process controller is changing pretty much everything to keep the voltage/current within the parameters it wants to see, to give you that stable arc, to compensate for shielding gas, stickout, etc. This is why I was thinking the voltage will change instantaneously when the wirefeed stutters - burning it way back and giving the bright flare.

    Either way, a burnback mid-weld will often flare - it's how it looks on aluminium MIG anyways, when you get a burnback it flares properly bright.
     
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  12. Davek0974

    Davek0974 Arse!, Drink!, Girls!

    Messages:
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    Interesting, thanks.

    Again, the two machines had the same fault - R-Tech I-Mig 160 was full manual and the new one is a Rebel 215 in synergic mode, just confi=uses matter more i think as I cant blame it on synergic mode.

    If a burn back can cause a flare-up then that IS a help because it points to a wire feed issue which could be a constant across machines.
     
  13. Hood

    Hood If it walks like a duck....

    Messages:
    11,402
    Location:
    Carnoustie, Scotland
    You said it tends to happen when the welder hasn't been used for a while, could it be a film of rust on the wire causing feed issues?
     
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  14. MCKDAVID Member

    havent read it all, but I have regular problems here with power, line voltage drops being at the end of a very long line... the electricity board installed a recorder which measured the actual volts drop. Testing was over two weeks, might be worth asking them to install one to at least prove the stability or not of the line.
    Same problem between two machines, did you transfer anything over from one to the other? for example the reel of wire. Had the same issue as bob, new reel was damaged being delivered, and the wire kept catching on that point, binned it too.. not worth the grief..
     
  15. slim_boy_fat

    slim_boy_fat Forum Supporter

    Puts up a right fight, doesn't it. :D
     
  16. eSCHEn

    eSCHEn Bit Wrangler Staff Member

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    Location:
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    That's what I thought, rusting/oxidising on some part. When used frequently it cleans it off and when left unusued it builds up and causes an issue when next used in anger.

    Gas doesn't seem likely as you'd get issues all the time, regardless of how long it had been left. As soon as you pressurise the system then it's purged effectively.
     
  17. Davek0974

    Davek0974 Arse!, Drink!, Girls!

    Messages:
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    Location:
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    I dont 'think' it was rust as the Esab wire was the copper coated variety.

    When i sold the R-Tech i either let the wire go with it or binned it form what i remember, the new one came with a roll of Esab wire so i used that.

    It could be power but i would have thought the CNC stuff would go mental if it was dodgy, i'm not saying it isn't power though.

    My money is on incorrectly set wire feed or something like that.

    I'll do some work with the cover open for a while and if it does it will try and see what s going on in there.
     
  18. Hood

    Hood If it walks like a duck....

    Messages:
    11,402
    Location:
    Carnoustie, Scotland
    Rust does form on the wire even when copper coated. I very rarely do steel with the Mig but I have a roll of wire here and some gas just in case the need arises.
    A couple of days ago I decided to hook up a standard Mig torch to the Phoenix 330 and try some steel with it as I have never used it with steel and it is sitting idle anyway. I got the reel of wire down off the shelf and I could see a fine film of rust on the surface but thought nothing of it but it just wouldn't feed right and I actually ended up with a couple of birds nests because I had wound the feed down too much to try and stop it slipping.
    After the second birds nest I pulled off a couple of layers from he reel and slackened off on the feed pressure and it has been perfect in all the tests so far.
    As I said I hardly ever Mig steel so I am not used to it but I could hardly believe such a small amount of surface rust could affect it so badly.
    This is the wire I pulled off and as you can see there is hardly any rust on it, it was more like a powder coating and I suppose think about it that loose powder rust helps reduce friction making it slip.

    ScreenHunter_717 Jul. 05 13.41.jpg
     
  19. Davek0974

    Davek0974 Arse!, Drink!, Girls!

    Messages:
    919
    Location:
    Hertfordshire
    Interesting, thanks.

    I'll concentrate any future investigation on the wire area, if and when it happens again.
     
  20. Davek0974

    Davek0974 Arse!, Drink!, Girls!

    Messages:
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    Location:
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    Just a refresher, no too worried about this now as it seems to only do it very rarely at present.

    Have been messing with the Esab in manual mode, different feed and voltage, mostly messing with voltage to see the effects. I twerked the voltage up way beyond the recommended, probably was about 22-23v at its max and what did i get - a flare up just like it was doing in sMig mode at the start of the thread. I seem to recall posting somewhere in this thread that the voltage display was high, something like 26v - seems to confirm to me that the issue is indeed voltage related and not wire feed or gas.

    Maybe the output is hyper sensitive to supply fluctuations? Not saying i get them, just looking for causes.

    Interesting, just thought i'd pass it on ;)
     
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