Advice on welding.

[A930Rocket]

I was doing some practice welding tonight and I had what I thought was a good setting from picture number 3. You can see the wire I was using the picture number 1 and the gas settings in picture number 2.

Then I fabbed up a hanger for my ground and gun. I thought the welds actually came out pretty good (for me). Pictures 4 and 5.

While welding the bracket, the wire came off the drive wheel and shorted on the positive lug. Picture 6. I straightened everything up and welded some more on the bracket.

I went back to doing a little more practice welding and now it seems as no matter what I do, I’m blowing holes in the sheet metal. Picture 7.

I have the power on the lowest setting, A, and the wire speed at 3.5 like before.

So what’s causing the blow through‘s and it’s almost like the weld is frothing, for lack of a better word.

Did something happen when the wire shorted out?

Edit 1. I’m seeing what looks like a lot of brown residue, whereas I did not see that before or as much.

Edit 2. Hopefully the pictures post right side up.

[908/930]

I'm not a Mig expert but have done my share. Inspect your nozzle and make sure no splatter is affecting gas flow, try changing the copper contact tip that the wire travels through, those don't last long and can cause the wire to get stuck. Also try holding back the wire by hand to make sure it is traveling out at consistent speed and not hanging up in the hose.

[cstreit]

5 and 7 not enough heat if I'm correct. See how it isn't flowing? ..I think you're moving the gun too fast to build up heat. Maybe slow the wire and your hands down...

[A930Rocket]

Originally Posted by 908/930

I'm not a Mig expert but have done my share. Inspect your nozzle and make sure no splatter is affecting gas flow, try changing the copper contact tip that the wire travels through, those don't last long and can cause the wire to get stuck. Also try holding back the wire by hand to make sure it is traveling out at consistent speed and not hanging up in the hose.

I think you might be onto something. I’ve been watching some videos and that was one thing that was mentioned causing porosity in the world.

I’ll take another look tomorrow after work.

[Jim2]

No shielding gas.

Do you have a fan blowing on or over you?

Disengage your wire feed tension lever and squeeze the trigger, listen for gas flow at the nozzle, turn regulator flow up/down to make sure the reg is working. Maybe when the wire contacted the hot lead it flicked up and melted into the gas hose just above you wire feed mechanism.

[Jim2]

Did you remove the torch whip from the machine? The brass end of your whip which engages into the wire feeder has a gas port between two o-rings, it must be fully inserted/seated before you tighten the thumb screw on the wire feeder, otherwise gas won't transfer into the whip.

Edit: gas should be about 20cfh

[Daves911L]

Originally Posted by Jim2

No shielding gas.

Do you have a fan blowing on or over you?

Disengage your wire feed tension lever and squeeze the trigger, listen for gas flow at the nozzle, turn regulator flow up/down to make sure the reg is working. Maybe when the wire contacted the hot lead it flicked up and melted into the gas hose just above you wire feed mechanism.

^^^Yup

[A930Rocket]

Thanks guys. Great ideas and I will check tonight when I get home.

I did remove the torch whip out of the machine because I was having a hard time feeding the wire after it broke. It felt like it was hitting the liner or something and it took me a while to get the wire fed into it.

[A930Rocket]

I did a quick check before I left the house and seems like I can hear the gas at the machine, but not the gun tip. I’ll take a look tonight.

[A930Rocket]

You guys nailed it. I took the whip out / in, checked everything and now it’s working properly.

What causes the small dimple in the weld? Any way to avoid it? A little more wire speed?

[908/930]

Are you set up with your electrode (wire) being positive? If not set up that way. I think the terminal on the right is the positive. If the wire is melting back when it touches the work it needs more feed, or less heat, looks like what it is doing.

[john walker's workshop]

A new liner can make a big difference. How old is it?

[A930Rocket]

Originally Posted by 908/930

Are you set up with your electrode (wire) being positive? If not set up that way. I think the terminal on the right is the positive. If the wire is melting back when it touches the work it needs more feed, or less heat, looks like what it is doing.

The electrode/wire is positive. I’ll do some more testing gradually feeding the wire.

[A930Rocket]

Originally Posted by john walker's workshop

A new liner can make a big difference. How old is it?

The machine is about 10 years old, but I’ve only run a couple of 2 pound spools of wire through it during that time. Lots of sitting around and years between use.

[Bill Douglas]

You're doing well 930.

Maybe keep the molten bit flowing. Practice on scrap metal. I go in little circles and slowly move the molten bit along. But the big dogs do a C shape and work their way along.