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Topic Review (Newest First)
02-01-2007 05:46 AM
Originally Posted by ChevyTruckGuy
First it got to be a 20A isolated circuit. Second it sounds like your wire speed is to low. Third did you check the drive roller to see if there set to the wright wire size. four open it up clean it up and there should be a chart to set it for flux or mig.

I think Graig stated out an excellent point about the circuit itself. You really need to have a good circuit! Even though it's a 20 amp ciruit, their could be a bit of resistance with connections to outlets. A lot of times outlets are just "backwired" in cheapo residential outlets. The backwire methood relies on just a small metal spring clip that makes poor contact. Definately have a dedicated circuit for the welder. I have a 120 volt unit as well. I have it off my compressor line which is 10 gauge. Use commercial grade outlet as well. At work, we have the same MIG as I have at home...since I ordered the work unit (HTP 140). I have found the same at work if I run the welder on a small extention cord or a distant outlet, having the similar problems you stated.
01-28-2007 03:04 PM
ChevyTruckGuy Cool, One more thing when you laying down a bead you should hear a smooth sound arc the smoother is sound the better the weld. Remember there is a speed you move the gun as you weld too. Position pulling gun to you not standing behind it like you do with stick welding.

Them there technique which is how you hold the gun and move it 1. The straight pull 2. the C pattern you make the letter C as you weld nice slow movements. 3. The circle pattern you make small oval circles as you weld.

Penetration the amount of heat need to bond the two metal together.
Well this can be seen my looking after you weld it should have a orange glow
which will turn to a heat ring.

To cold the edges of the weld will not melt in to what your welding and will fail.
To hot and you can get burn through warping. Under cutting , Which is the edges of the weld and melted away the material your welding. The bad thing hear is it could lead to a fracture a long the under cut edge.

That a basic deal for you to look at as you practice welding

Hey guys help me out if I for something.

01-28-2007 12:16 PM
zimaad thanks for all the input guys. I put down a few decent beads just a bit ago. I blew out the insides of the unit(it was a bit dusty/dirty in there) and also blew out the liner. Tension on the drive seemed fine. I think I just didn't have the wire speed up high enough. At low speeds it was doing the on/off arcing but once I got the speed up enough it sustained the arc. Worked pretty durn good too. I'm just starting out restoring the metal work on a 62 Austing Healey Sprite. The person who owned the car prior to my dad back in the 60s cut a big hole out for a radio. I tackled the simple task of cutting a piece of sheet metal and welding that in today. I got through tacking it good then the welds started pitting and cracking -- out of gas!!

I'm pretty excited to have my first welder working now. Here's a link to what I picked up by the way. Thanks again for the help!
01-28-2007 11:17 AM
347mazda How tight do you have the drive wheel. Might not have it tight enough letting the wire slip. Also how tight do you have the wire spool might have it to tight and causing it to bind.
01-28-2007 10:58 AM
BoneHeadCustomz This is all great info, additionally check the ground. Make sure the clamp is connected well to the cable, and in the machine as well.
01-28-2007 10:32 AM
oldred I agree with Chevy and Mikey it sounds from your description that the wire is not feeding fast enough or erratically. When you pulled the wire through did it come through easily and smoothly? A bad tip is a simple but extremely common cause of this problem so is it new? Like Chevy suggested check the drive rollers and make sure they are right ones for this wire, also have someone else watch the rollers while you are trying to weld and make sure they are running smoothly.
01-28-2007 06:50 AM
zimaad I checked and it has 30 wire and .8mm/30 tip. I can pull the wire through the gun when I release the drive wheel. It is on a dedicated 20A line. My garage has a 30A/110V service running to it. I have that going to a double 15A breaker for lights, etc and a dedicated 20A circuit for my welder. The wire in it looks good. Definately solid, not flux. The polarity is setup according to the chart on it for MIG welding.(not flux) I'll try cranking it up in power then increasing the wire feed and see what happens.
01-28-2007 01:38 AM
powerrodsmike Does the wire burn back into the torch and then drop off onto your base metal? If that is the case then I ask this...

Is the liner shot or kinked? It sounds like the wire isn't being fed fast enough. Check the wire feed rollers, cable liner, electrode, (make sure it is the right size and not excessivily loose),and reel tension. Check to see that the wire unwinds smoothly from the roll and isn't all tangled up. (they call that "birdcaging".
You should be able to release tension from the drive roller and draw the wire through the cablehose from the torch end with relative ease.
If you can't pull it through by hand then check the things I mentioned.

Also, you would do well to get a new roll of wire. .023 or.030 er70s6 is good general purpose wire.

Was the unit set up for gas when you bought it? I wonder if there is some flux core wire in it? It should weld ok with gas unless you switched the polarity. (should be ground positive for gas welding)

Does the wire hit the base metal and then melt without penetration? I'd guess that then the polarity is reversed or your wire speed is too high.

Play around some..Set the heat setting all the way up and bring the wire speed up till it welds. Use a piece of 3/16 so you aren't bothered by burning through. If you cant get it to weld after all of that then you might have issues with the circuit board or a diode.

Hope this helps,
01-28-2007 01:24 AM
ChevyTruckGuy First it got to be a 20A isolated circuit. Second it sounds like your wire speed is to low. Third did you check the drive roller to see if there set to the wright wire size. four open it up clean it up and there should be a chart to set it for flux or mig.

01-27-2007 09:37 PM
New MIG - unstable arc

Hey all,

I recently purchased a used Schumacker Turbo 145 MIG welder. It's a 120V unit and I picked up a tank of C25 gas to go with it. I just tried welding for the first time today. The arc doesn't stay on to heat up the metal so I just get some plops of melted wire on the base metal. The electrodes are properly hooked up for gas welding and I have it plugged directly into a 20A outlet. It's been a few years since I welded, but I don't think I'm THAT bad!. I fiddled with some different settings and it was the same on/off arc with all heat settings. Any help is appreciated.

- Drew

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