[crouchy]

Hi guys,

I'm still having some problems with vertical up mig. I use the right techniques (upsidown V) reduce power by 15-20%. The weld pool starts to undercut and crowning about a 3rd of the way up. If I turn it down anymore I feel there's gonna be lack of penetration. It's a bit hit and miss I have laid some respectable vertical up beads but it's still not consistent. I'm wondering if the machine I use with the three earth terminals may have something to do with it?? The pool dosent cool quick enough, I use 5mm plate (3/16 for you yanks) hot rolled. I have heard mill scale can have an effect?

[AKweldshop]

Gotta keep the wire feed speed down.

[crouchy]

Here's what it looks like

[Coldman]

Now put it in a press and break it to see how well it is fused. That will tell you more about how you are going than anything else.

[Superiorwelding]

Looks to me that you just need to hold the sides a little longer so the profile of the weld will flatten out a little more. What are your settings (wire size, gas, volt, amps, etc)? That will help as well. I always tell others that it should be as hot as you can stand and look like it is falling out (at least in your mind) but laying in good.
-Jonathan

[crouchy]

I use 0.8mm wire (1/32) argoshield universal (Boc) think it's 12% co2 2% O2 and 86% argon it's recommended for material 4mm too 8mm I believe

[noddybrian]

Wire speed & volts are really needed to judge if you have a setting that should work on that material as opposed to a manipulation thing & as most of the better informed members are stateside the gas / wire diameter combo is going to hard for them to judge - hopefully Jonathon will be able to help - can i ask who chose 0.8mm wire ? if you do a wide mixture of thicknesses mostly thinner than 5mm I agree it seems appropriate - if however you are doing almost all 5mm & sometimes more then I think you will struggle to get enough heat in fillet joints as per your picture without approaching spray or at least globular transfer neither of which are conducive to vertical up - if you do mostly open corner / gapped butt or V prep it's likely good - might it be worth trying 1mm wire - I keep this in my general purpose go to machine unless I've got heavy stuff coming in & find it has probably the greatest flexibility of material thicknesses at the light end of fab - most shops around here seem to do this also - how mission critical are the parts your making ? is full penetration required ?

[crouchy]

Alright mate, nah I'm only trying to master this as I want to take another test. I mainly weld thin gauge box/tube sheet metal. I do heavyer materials too but not as much and it's normally in flat position. I do alot of out of position welding on thin gauge work so getting it right on thicker first is normally the way to go