WeldMaster Why is my MIG welder popping, and which setting do I change?
Most of the time the arc is popping because voltage is too low for the wire speed: the wire stubs into the puddle instead of melting off smoothly. Set both for the same amperage and the pop settles into a steady sizzle.
What does the popping tell you?
A loud, irregular crack with a spray of little balls is a cold, stubbing arc. A quiet, even sizzle is what a tuned short-circuit arc sounds like. WeldMaster's own Excessive Spatter entry describes the target as a steady bacon-sizzle instead of a harsh crackle.
Check the boring stuff before you touch a knob. A worn contact tip, a rusty spool, an empty bottle, a ground clamp on paint. All of them pop, and a bad ground clamp alone can cost an hour of troubleshooting.
How voltage and wire speed have to move together
On a MIG machine wire speed sets the amperage, and voltage has to sit in the right window for that amperage. WeldMaster uses the same rule: wire feed is the amps times a burn factor (1.6 for .035 wire), and the short-circuit voltage window starts at 13 V around 40 A and rises to 19 V at 200 A, then adds 2 V on top.
Take 1/8" mild steel, .035 wire and C25 through the free MIG screen. Centre of the range is 125 A, and the app shows 16.2 – 18.2 V with Wire Feed 180.0 – 220.0 ipm. Now push the wire to 250 ipm and leave voltage alone. By the same maths that is about 156 A, and the voltage window moves up to 17.4 – 19.4 V. If you were sitting at 16.5 V, you are now roughly one volt under the window, which is where the app's own spatter entry says stubbing starts.
| Wire speed | Amperage it implies | Voltage window | What a 16.5 V setting does |
|---|---|---|---|
| 200 ipm | 125 A | 16.2 – 18.2 V | Inside the window, low end |
| 250 ipm | 156 A | 17.4 – 19.4 V | About 0.9 V under the window: likely to stub |
The 250 ipm row is a manual calculation using the app's formulas, not a screen you can open: the app takes thickness in and gives amps out, not the other way round.
How to dial back in with WeldMaster
- Open MIG under Calculators. It is free.
- Pick Mild Steel under Material and set Thickness to the metal on your bench.
- Choose the Wire Size on your spool and the Shielding Gas in your bottle.
- Read Amperage, Voltage and Wire Feed under Suggested Settings. Set the wire speed to the middle of the Wire Feed window first.
- Raise voltage a volt at a time on a scrap piece until the crackle turns to a steady sizzle, and stay inside the Voltage window.
The free Troubleshooting list has an Excessive Spatter entry that says the same thing from the other side: voltage too low for wire speed comes first, wire speed too high second, 100% CO₂ third. Its fix is to nudge voltage up a volt at a time, then back the wire down.
Popping on thin metal
On 16 gauge (0.0598") the app gives 54 – 66 A and 13.7 – 15.7 V with .030 wire at 113.0 – 138.1 ipm. The window is narrow, so a volt of error is a much bigger share of it than on 1/4" plate. Nothing in the app lets you hear the arc or checks that you stayed in the window; you still have to set the machine by hand.
What the app will not tell you
The app does not diagnose a popping arc. There is no entry named popping, and you cannot type in what your machine is set to and get told which knob is off. You get the target window and do the comparing yourself. Save to My Setups needs Pro, so the settings that worked need to be written down separately, for example on tape inside the machine door.
Questions and answers
Why is my MIG welder popping?
What causes popping when MIG welding thin metal?
Does the MIG calculator in WeldMaster cost anything?
Is MIG crackling the same as spatter?
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- MIG Settings for 1/8-Inch Mild Steel With .035 Wire · WeldMaster
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