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Thin weld bead

3.3K views 11 replies 5 participants last post by  wirehead  
#1 ·
Hey guys!, Ive been welding for about 5 months and have a mig welder that I am running flux core in. but every bead I get is really narrow.. How do I fix that??, any answers will be greatly appericated!

-Liam
 
#2 ·
Sounds like you may be moving to quickly and possibly have the settings wrong.

To really know we would need to see a few picts of the weld/s along with the machine used, wire size, voltage and wire speed settings and material thickness. The more we know, the better we can answer your question.
 
#6 ·
1st thing your welder is way under powered for 1/4" material no matter what the manufacturer might say. Expect the max thickness you will get decent welds on will be roughly 1/8".

I'd still guess that part of your issue is going too fast. That's a typical issue with new welders. For 1/8", I'd set the heat or voltage to max and adjust your wire speed accordingly. I'd probably start at 6 out of 10 and adjust from there myself without suggested settings. with .030 wire your wire speed will be slightly higher than if you were using say .035 wire so you get the same deposition.


Again picts will tell the story.
 
#9 ·
Way too cold. Go to thinner material and up your voltage.


No you will not get full penetration on 1/4" with a 120 amp unit. You won't even get good penetration welding both sides of a 1/4" piece with a machine that small. The problem is one of mass. The 1/4" will suck up too much energy so your fusion into the base material will be poor. The weld material will simply just sit on top and not bond well to the base material. You'd be maxing out a 180 amp mig to be getting decent penetration on 1/4" and even then with but joints you'd need a good bevel and decent prop to get good welds. A 200 + amp class mig would be a better choice for a steady diet of 1/4".

With only 120 amps max to work with and a short duty cycle, 1/8" would be pushing that machine. You shouldn't have issues with penetration on 14 ga. Small 110v machines are sheet metal units. The problem is lack of input power.


One other issue you have is poor prep. Don't try to weld over paint and rust, especially if you are under powered to begin with. You need to grind down top shiny steel. A power wire brush won't cut it as all it does is polish the rust, not remove it. Granted if you have enough amps you can weld thru some rust and scale, but it's a bad habit to get into. All those contaminants will give you a poor weld.
 
#12 · (Edited)
I'd check your polarity. For physical reasons I don't pretend to understand, fluxcore needs wire at negative potential (DCEN) whereas mig needs the opposite. IMHO, using the wrong polarity results in scrawny looking beads

Fluxcore should be able to blast through thin walled tubing EASY PEASEE. Takes a lot of practice to avoid doing so!