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  • cruizer
    replied
    Keep on forgetting the stuff that caused the most strange problems, and yes the stupid stock wavy aluminum ground clamp was on top of the list in both Miller and Lincoln.

    Leave a comment:


  • H80N
    replied
    Here is an old thread that might be helpful

    http://www.millerwelds.com/resources...92-252-popping



    BTW... BukitCase's thought about the ground clamp is a good one
    Last edited by H80N; 02-22-2016, 01:34 PM.

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  • BukitCase
    replied
    Sounds like a 2-part problem - your board for one. Gun is obviously OK, but nobody's mentioned GROUND yet - if you're still using the original CRAP ground clamp I'd replace it with a REAL one, also check/clean connections on the ground clamp in the machine... Steve

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  • BroncoCrawler
    replied
    Both machines are setup to positive guns. All tests were done using the same bottle and regulator just switched from one machine to another. Again Same size wire and settings. My machine will not hold a consistent puddle while my dads will. Mine starts to pop and studder and then you have to let up. Mine seems OK in a perfect scenario. A flat perfectly beveled long weld and its fine but you start doing a roll cage or other odd shape and its **** impossible to weld with it other then tack, tack, tack tack (laying dimes) method which I do not approve of on structural welds.

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  • H80N
    replied
    Originally posted by BroncoCrawler View Post
    OK well its not the gun. My dad brought his welder to my shop so we have them side by side now. My gun on his machine welds perfect. his gun on my machine same crap. both machines are setup for 230v input and both tested on the same power outlet. I checked resistance on the weld stabilizer and both machines are identical. there is a difference on resistance on the heat sink (red/white wires) my machine measures 13.8 on both pairs while my dads measures 20.0 we also switched boards between the machines and mine seems to weld better but still not right. my dads machine with my board seems unsuable but put his board back in and it welds perfect..... I'm really at a loss my serial number is LB170617 my dads is LF289626
    How about gun polarity..??

    Hard wire with gas should be Positive at the gun... Gasless fluxcore should be Negative at the gun
    Last edited by H80N; 02-20-2016, 05:08 PM.

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  • BroncoCrawler
    replied
    OK well its not the gun. My dad brought his welder to my shop so we have them side by side now. My gun on his machine welds perfect. his gun on my machine same crap. both machines are setup for 230v input and both tested on the same power outlet. I checked resistance on the weld stabilizer and both machines are identical. there is a difference on resistance on the heat sink (red/white wires) my machine measures 13.8 on both pairs while my dads measures 20.0 we also switched boards between the machines and mine seems to weld better but still not right. my dads machine with my board seems unsuable but put his board back in and it welds perfect..... I'm really at a loss my serial number is LB170617 my dads is LF289626

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  • ryanjones2150
    replied
    Maybe you should stop doing that Bob!

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  • aametalmaster
    replied
    Originally posted by ryanjones2150 View Post
    Do people really do that? Drag the welder around by the gun like its some sort of leash on a dog? I wouldn't even consider doing that!
    I see it everyday...Bob

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  • cruizer
    replied
    are you sure its connected for the correct input power as usually if the gun is damaged the digital display will read "too Hot". so a serial# would be handy to verify the components.

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  • BroncoCrawler
    replied
    well I switched the guns with my dads and it does actually seem better. I have a big weld project coming up so i will know %100 if its fixed then.

    thanks David

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  • H80N
    replied
    Originally posted by ryanjones2150 View Post
    Do people really do that? Drag the welder around by the gun like its some sort of leash on a dog? I wouldn't even consider doing that!
    WADYA MEAN...??

    I thought it was for yanking it round the shop....

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  • ryanjones2150
    replied
    Do people really do that? Drag the welder around by the gun like its some sort of leash on a dog? I wouldn't even consider doing that!

    Leave a comment:


  • H80N
    replied
    Sounds like you have replaced everything in the gun but the power conduit....

    Try a "KNOWN GOOD" gun....

    somebody may have pulled the welder by the whip and damaged it.... that could give you erratic performance.... happens all the time...

    Leave a comment:


  • BroncoCrawler
    started a topic MM251 problems

    MM251 problems

    OK this will get a little long but I'm pulling my hair out and would like some guidance. The machine in question is a MillerMatic 251 that I purchased used about 2 years ago. The reason I bought this welder was because in 2005 my dad bought a brand new 251 and so I am very familiar with the machine and layed down a lot of beads with it over the 10 years I used it at his shop. When I went to buy my machine the 251 was no longer available so I found one used that appeared to be in excellent shape. I layed down a couple test beads and everything seemed fine.


    Well I tried to use the machine over the last several years and something is just not right with it. my machine is a 2001 build and my dads is a 2005. identical machines, same size wire, same 75/25 gas, however these two machines weld nothing the same. my machine has to be turned up much hotter to achieve the same welds on the same thickness. also mine seems to chatter or loose an arc mid way through welding. its hard to explain but it is just much more touchy then my dads and much harder to lay a nice bead and also harder to start a clean arc.

    I have replaced the liner, the rollers, the tip, rebuilt the gun, installed wire cleaners and lubers. changed wire, both in size and brand nothing helps. I also changed the gas regulator. I used all genuine miller parts.

    I called miller tech support yesterday and they were very helpful! Thank you Josh. We tested welder output which he said was ok. checked resistance on the pairs of red and white wires. also apparently ok. then checked the weld stabilizer resistance. he said these readings were not what he was expecting. he recommended checking this against my dad's which i will do this weekend but my question is from my description does a bad weld stabilizer make sense? are there other things to check? is there a trouble shooting guide to help me walk through testing it?

    I am frustrated with my machine and confident its not my skills. My dad also has used my machine and says it is difficult to use. its not that it doesnt work its just not quite right when compared to his.

    Thanks or you time

    David
    Last edited by BroncoCrawler; 02-17-2016, 10:28 AM.
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