settings for last pass in multirun weld

[w124]

Stop weaving. Stop whipping the torch. A mig run should look smooth, clean, flawless. I will take some photos later of what you should be looking for.

so there is a straight run with no weaving at all, moving as slow as possible, poor quality photo. 31V


and theres a thread on reddit about weaving and penetration. pic related.

https://www.reddit.com/r/Welding/comments/2rsx6t/discussion_gmaw_to_whip_or_not_to_whip_tis_the/

"""You can get more strength/penetration with a straight no-oscillation bead, but your gun angle has to be perfect or you'll miss the root so we have everyone run an oscillation to widen the bead profile."""

^ so how it looks with multirun mig?
let's say the root pass is done correctly. what would i look for would be geometry and smoothness

something like this.

and as its growing up its harder to keep the geometry and smoothness,

3rd run counting from bottom last pass aswell

 

[Richard.]

Imagine the heat build up on that.
I know it’s for practice but just do 3 straight runs and stop. Any more and it’s spoiling things.
Moving too slow only leads to lack of fusion defects as the pool rolls over in front of your wire. It doesn’t increase penetration but it does increase heat input going in and it does increase the amount of reinforcement you stack into the joint. It decreases productivity also. Pick up the travel speed and bang one straight run down the joint. Leave it to drop below 100° and bang down another on the bottom toe. This second weld should cover around 60% (2/3) of your root run. Leave it to cool below 100 and bang another down at speed on the top toe of the second run. Job done and a great joint.

 

[Richard.]

Here are some settings for you.
400mm/min travel speed
1.2mm G3Si1 CF Wire
Around 260-280A, probably 30V

Stunning example brad.

 

[w124]

the bead done on tractor looks bigger compared to the others you posted.

i dont have a fillet gauge, but i belive this is somewhere near a6 maybe less but my travel speed might be quicker than 400mm/min.
if i had time to lay another bead i would reduce WFS by 0,2 m/min and see what happens, guess that should work better.
31V CV 1,0mm ER70S-6 esab wire

Imagine the heat build up on that.
I know it’s for practice but just do 3 straight runs and stop. Any more and it’s spoiling things.
Moving too slow only leads to lack of fusion defects as the pool rolls over in front of your wire. It doesn’t increase penetration but it does increase heat input going in and it does increase the amount of reinforcement you stack into the joint. It decreases productivity also. Pick up the travel speed and bang one straight run down the joint. Leave it to drop below 100° and bang down another on the bottom toe. This second weld should cover around 60% (2/3) of your root run. Leave it to cool below 100 and bang another down at speed on the top toe of the second run. Job done and a great joint.

Richard im moving as slow as possibe, but i dont want the puddle to take lead whether its weaved or not.
also everytime im letting it cool after 2 passes.
i can feel it how much heat is enough.

at least im not writing guides like this one
https://duckrolldesigns.com/2016/03/12/multi-pass-weld-practice/

 

[Richard.]

im moving as slow as possibe,

Why?

 

[w124]

Why?

With the 1.0mm wire you don't want to be going much bigger than 6mm fillets.

what Brad said, when i run production work its usually a3 / a4 welds most of the time with 1,0mm wire. i set the machine high for a6 welds but then my movment speed increases to get that desired "a". when i weld something heavier i use 1,2 wire and dont run that fast. but thats for production work.
when i have time to do samples most of the time i use max capabilities of the wire diameter i.e. 1,0mm for a6 bead
just to make the puddle bigger, because its alot of fun or you might call it deviation

im out from work for 3 weeks but i want to ask you about huge current drops
had it twice with AC TIG
now with MIG
just like this, 32V looks like 10V less
ground was hooked to a welding table and with the 1st pic i grinded it from the bottom to provide a good ground because there was a lot of mill scale.

 

[Mid Wales welder]

Just to add my two cents. This was welded at about 28-29v 240-250a 1mm G3Si1 wire 14mpm, probably about 350mm/min. With just a wire brush in between and allowd to cool for a min or so before last run. Nice and straight, no weaving at all. There’s more than one way to skin a cat though and this is just one of them lol.
The theory behind not weaving is that it slows the travel speed and therefor increases heat input, this in turn can increase hardness/toughness values and lead to failures. As with everything in welding there is a lot more to in than that though