Bad bacon or Welding doesn't sound right

[KMinAF]

Since upgrading to MIG from flux core I am having difficulty getting the right wire speeds. Most recently while attaching rear spring hangers on a project truck, the weld was pulsing. I tried adjusting wire speed fast and slow and while it did have an affect I was never able to get that continuous bacon sizzle sound. The welds appear to be fine with good penetration. Are there other factors that could cause this? What might I be doing incorrectly? Could it be a machine issue? This seems to be an issue regardless of what I am welding. Thanks.

Lincoln Weld Pak 155
30 solid core 25/75 mix
3/16 plate to Toyota frame
metal cleaned and prepped
ground clamp on clean metal and close to welding area
Machine setting as listed on panel: E and 7 1/2 (varied to get better weld)

 

[ScottS]

If you have not you may want to try a different ground clamp if you still have the one that resembles a battery charger clamp. Or use a pair of vise grips to pinch the wire down good just to see.

Looks like you have all the rest covered.

Also check to see if your wire rollers are set properly. Not to loose and not too tight. Some rollers are serrated and will deform the wire when cranked down tight and cause some issues. Back off the roller tension and tighten up just enough to make the wire feed and not stop, it should roll up like a slinky when you run it out against a surface you are not grounded to.

Did you swap polarity from flux to solid?

Just a thought.

Scott

 

[srmofo]

Check the polarity

 

[e-tek]

ScottS knows what he's talking bout!

 

[DCarr]

how about the wire feed rollers, are they tight enough ? If they are lose, it can cause the problem your having.


edit: ScottS covered it

 

[gerahead]

welding outside? Wind can blow your cover gas away and cause problems like this. L8r

Jim

 

[aka Larry]

I don't have an "E" setting on my Lincoln 140 (mine goes to "D"), but "7-1/2"" on the wire speed sounds high, especially for 0.030" wire. Pulsation is generally caused by the wire speed being too fast, so I'd try slowing it down first. Also like has been said, when switching from flux-core, be sure to reverse the polarity of the leads inside the cover.

 

[1967marti]

Check your wire rollers inside the machine. They must be TIGHT... Also there are different rollers sizes for different sized wire; the rollers should have a gauge or gauge range to match up with the wire you are using.
If your shielding gas was getting blown away you would be getting horrible looking welds full of holes and lots of soot/burn marks.
A bad ground could be another cause of your problems... You must grind down to shiny metal where your grounding clamp is attached to… SHINY METAL!!
Also make sure the metal you are welding is clean and free of dirt/rust.
Flux core is a lot more forgiving of dirty metal, it burns hotter and penetrates deeper than the same gauge wire (and same settings) if used with a shielding gas. You may not have the welder turned up high enough now that you switched from shielded flux core. Try turning up your welder’s amps and maybe turn down the wire speed and see what you get.

 

[KMinAF]

Thanks for all the input, the only thing that I haven't checked is the roller tension. I will do that this weekend.

 

[csp]

Check the polarity

^^^This^^^^ Polarity is reversed when going from flux core to shielding gas.

 

[aka Larry]

Try turning up your welder’s amps and maybe turn down the wire speed and see what you get.

Wire speed = Amps. I think you mean turn up the voltage, and turn down the amperage.

 

[e30bradley]

its more important for the weld to be strong than for it to look good. although looking good is always a plus.

 

[csp]

From the other side, if a weld looks like a blob of peanut butter mixed with birdshit, it isn't strong.

Lots of craptastic welders claim their welds to be strong, but it if it a weld looks like ****, it's ****. Xrays prove this. Cut a crappy weld apart and you'll see.

 

[aka Larry]

Lots of craptastic welders claim their welds to be strong, but it if it a weld looks like ****, it's ****.

I agree, and hear this excuse often. Most people who can lay down a nice bead also know how to make it strong. ZTFab's welds are probably the weakest welds evar!

 

[Sureshot]

How often does a person need to change the liner in the cable?

Do not set your rollers to tight. If you do and stick the wire in the tip it will pile up at your rollers. I leave them loose and feed wire into something(ungrounded) until it pushes on the object but not so tight as to have it pile up in the machine.

 

[z28snksknr]

I had this issue out of no where on my MIG and it was the tension on my spool. It was too tight, so it was slipping in the rollers and slowing my wire speed down. It was at the end of the roll, so i jsut swapped it out and its fine now.

But seeing the other, more valid suggestions above, I'll guess my issue was isolated to me. Just offering to keep in your mind to check.

 

[KMinAF]

I figured it out!

The wire speed knob had spun on the shaft so after "recalibrating" the knob everything works according to the charts. Love that sizzling sound!

Thanks again for all the ideas.