bad welds "how to fix it"

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PostPosted: Tue Oct 08, 2013 7:12 pm
Cant figure out my bad welds. I am a DIYer at best when it comes to welding but have never struggled this much. Ive attached pics of my MIG setup. Its pieced together from a HD Weld Pak 140 with .030 Clarke Wire and Clark regulator on 75/25 Argon/CO2. I just set this up for MIG welding. Was using flux core wire prior to now with much better results. I started with the volt and wire speed per weld paks recommendations at 2 and C for .030 wire and 18 gauge sheet metal. I set the gas at the recommended 14 to 18 L/m. You see the pics of the best welds I could get no matter what I adjusted on the welder.

First I noticed the gas settings on this gauge set are in the red and when you pull the trigger to weld you can hear the gas coming out very fast. It will actually blow dust off the top of the car. I turned the gas down in increments trying again and my best looking welds are when the gas was completely off. The wire is a solid core wire for use with gas.

Oh yeah I did reverse the polarity in the welder by changing the ground clamp to "-" and the feed line to "+". That's one thing I have not tried is switching these back to how they were but even Lincoln inc. tech support said to leave it this way.

Would switching to a .025 wire help?
Any input is appreciated. Thanks
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gauges.JPG
Last edited by pastrozyk on Tue Oct 08, 2013 7:52 pm, edited 1 time in total.



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PostPosted: Tue Oct 08, 2013 7:32 pm
Well the website would not let me upload any photos so I will try to describe the welds. They look like warts with pits all in the top and when I have the gas up to recommended settings there is a hole in the center of the weld. the lower I turn the gas the prettier the welds look. Still warty looking even with the gas off. I don't think there is trash or debri because I get that sizzling bacon sound and very little if any splatter. I feel my voltage and wire speed are close because I can burn but not blow through and can fill pin holes pretty well.
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weldsII.JPG



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PostPosted: Tue Oct 08, 2013 7:35 pm
Trying to load more pics
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welder.JPG



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PostPosted: Wed Oct 09, 2013 4:10 am
looks like your trying to weld over normal paint, im no pro, just a diy like yourself but I would grind the paint back to metal and try that, also wat gas are you using??
krem



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PostPosted: Wed Oct 09, 2013 9:47 am
It is actually bare metal. The photo may look a little deceiving. This area was some small pin holes where sand blasting blew through I then DA the sandblasting and tried to weld these spots. After tinkering with it I actually filled the holes pretty well and grinded down smooth. I just have alot more welding to do, (i.e. quarter panel skin) and want to have as pretty job as possible for less work later and to hold together. Ive done some sheet metal welding before but years ago and did not have near the trouble with the welds or setting the welder correctly. This is my first time using this welder with a MIG setup so Im thinking something is not working together correctly.

Gas is 75 % Argon and 25% CO2

Thanks for the input



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PostPosted: Thu Oct 10, 2013 8:10 am
ok you say your welds are better with the gas off ? that doesn`t make any sense , it is possible to have a bottle of contaminated gas, 12-15 psi should be enough shielding gas, also make sure your wire is clean, a spool of wire not used often and left uncovered will get some contamination on it, and make sure there is nothing that will blow your shielding gas away when your welding

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PostPosted: Sat Oct 12, 2013 12:51 pm
did you change the polarity after you switched from flux to welding with gas??? that makes all the difference in the world
if its blended its splendid



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PostPosted: Sun Oct 13, 2013 8:51 am
What kind of Gas are you using? whats the Mix???? "Ditto" what Bondo merchant said Double check make sure you got that right!!!! looks like you don't have any gas on at all gas turned down to low.
Regulator may be bad
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PostPosted: Fri Nov 15, 2013 9:37 pm
bondo merchant wrote:did you change the polarity after you switched from flux to welding with gas??? that makes all the difference in the world


$10 says this is it.

I own a cheapo HF 170amp MIG/FLUX welder, it does the job considering I use it once every 2 years, anyways, I always weld with gas, I lent it to my father who wanted to weld with flux, but he never switched the grounds from gas to gas-less, and the welds were terrible with no penetration.

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PostPosted: Fri Nov 15, 2013 11:30 pm
Your gas flow gauge is in L/min and should be set to 7 with trigger pulled. This will equate to 15 cfh.
Set your heat and wire speed at the recommended levels to start.
Adjust your heat at first leaving the wire feed alone. Try to produce a spot weld with good penetration by increasing the heat a little at time. Once you get the heat set begin increasing wire feed until the weld looks full.
Most beginners are afraid of burning through so they end up with blobs of metal sitting on top of the steel rather than a pool of metal forming a solid weld.
1968 Coronet R/T


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