[tweake]

just doing some practice on scrap.
did a nice weld if i do say so myself. put it in the vice, bend it over and snap. *****!
poor penetration on one side, ripped out a bit of base metal.

thats why it pays to test stuff.

[ex framie]

So, come clean, what was your prep, what were you welding?
I've seen mig do that on mill scale with incorrect settings, looked lovely until it fell off when hit with a chipping hammer.

[tweake]

i think it was 4mm steel, cleaned, fillet weld.
but set a bit cold and didn't get it in there well enough.
used the same settings on 3mm steel and it was a lot better. bend the plate in the vice, tho broke it where i wandered off course and didn't get fusion on the side.

it was a good reminder that just because it looks ok doesn't mean its any good.

just having some fun trying to dial the mig in. chart settings seam to be some what low.
running 0.8mm er70s6 wire, argoshield universal.

[tweake]

just a chance for a play today.
bumped up voltage and decreased wire speed a bit.
did one that ended up laying on top. broke the weld off and you can see bright metal where the weld was. no fusion what so ever.
got it up to 18v 100amp ish and its getting in there now. very hard to break the welds and ripping out the base metal when i do break it.

just very surprising how good looking those cold welds where and how weak they are.

[MinnesotaDave]

just a chance for a play today.
bumped up voltage and decreased wire speed a bit.
did one that ended up laying on top. broke the weld off and you can see bright metal where the weld was. no fusion what so ever.
got it up to 18v 100amp ish and its getting in there now. very hard to break the welds and ripping out the base metal when i do break it.

just very surprising how good looking those cold welds where and how weak they are.

Lowering wire feed speed decreases amperage. Amperage (wire feed speed) controls penetration (depth of fusion).

Voltage affects bead width and height. More voltage = wider and flatter. Less voltage = taller, thinner beads.

When your bead wasn't penetrating, increasing WFS would be the correct step, then increase voltage until it runs right.

[tweake]

thats basically what i was doing originally, but it wasn't getting better.
only dropped WFS a bit to keep heat about the same. judging by the amps i don't think its to low.
volts x amps = heat.
penetration is now better but its rattling like voltage is to high.
of course the other factors is travel speed and stick out. so odds are i'm screwing up something there as well.
having real trouble seeing the puddle with the gun in the way.

i'll have to raid the scrap bin again, and try again.

[MinnesotaDave]

thats basically what i was doing originally, but it wasn't getting better.
only dropped WFS a bit to keep heat about the same. judging by the amps i don't think its to low.
volts x amps = heat.
penetration is now better but its rattling like voltage is to high.
of course the other factors is travel speed and stick out. so odds are i'm screwing up something there as well.
having real trouble seeing the puddle with the gun in the way.

i'll have to raid the scrap bin again, and try again.

Lincoln actually ran the experiments and when only changing one variable, amperage (WFS) is the deciding factor in depth of fusion.

Voltage must be properly balanced to the amps you've set to run properly, but in general voltage is only responsible for bead profile - things you see at the surface.

[tweake]

done a bit more testing.
i think i'm still a bit low on the WFS.
did some runs to see what it takes to melt right through. gives me a good idea on whats to hot and whats to cold.
i have run out of that size steel so will have to raid the scrap bin soon.

once i get a handle on wire speed and volts i can get to work on technique.