Mig welding alloy

[Gavin_d]

Hi guys. I'm quit experienced in mig welding alloy but since using a new machine I'm struggling. The welds a full of soot. Gun angle is all correct but I've forgot what the optimum gas flow I used to prefer is. Never had to change it for so long I've forgoten.

The welder is an old murex one but not sure of the model.

So if anyone knows of a good gas flow could you please be kind and let me know what you use.

Many thanks all.

 

[Jim Davey]

What kind of torch have you got as reccomended gas flow rates alter with shroud size.
A Binzel 501 for instance has a reccomended flow rate of 16 lpm on ally.

 

[Gavin_d]

Hmm I'm not so sure. It's the bigger type of standard mig guns with the long surround. It's a murex tradesmig 251. Not the most ideal welder for alloy mig welding.

 

[Jim Davey]

MB 25 by the sound of it. Do you have a tip flow meter so you can accurately set flow at the nozzle?

 

[Gavin_d]

No I don't. Only setting from regulater. I know this is not the most accurate.

 

[Gavin_d]

Second torch down.

 

[Jim Davey]

Not accurate at all. I'd say you'll be somewhere in the region of 10 lpm at the nozzle.

 

[Gavin_d]

I will get one next time welding suplie guy is down. Is 16lpm the recomended then?

 

[Jim Davey]

That's an MB36, almost the same bore size as a 501 (top pic) so I'd suggest 15 lpm, that will sound like quite a lot to the untrained ear but you need a fair bit more gas on ally with a big gun.

 

[Gavin_d]

Nice one thanks. Keep suffering from burnback too and eating through tips. My old set up had a push pull torch and the machine had a burnback adjuster. Was a migatronic set.

Hate using a normall torch. The slightest kink in the lead and the wire slows down mid weld and makes a mess. Welding up curtain sider truck bodies so always on the move with welder. Wish I could have my old set back!

 

[Jim Davey]

Buy a push pull gun for your machine, or a spool on gun.
How long is your MB36?

 

[Gavin_d]

It's a machine at work. I have a better set at home lol. Will talk to boss and see what he says lol. I've had to move units that why Im having to use a different machine. Think it's a 4 metre it has on it.

 

[Jim Davey]

That will make things worse, 3 mtrs is best for ally 141.0015 is the part number for the 1.2mm ally specific tips, I take it you are on 1.2mm wire?
You need a Teflon/plastic liner and the correct drive rollers too really, anything else will cause you trouble.

 

[Gavin_d]

Yes we had a meter on it but kept jamming. Found a 4 meter with Teflon yellow liner so put that on. What I might do is take the liner out the 4 meter and fit in the 3 meter. I've been told it has the correct rollers. I will check on them tips. Thanks for info!

 

[Jim Davey]

My pleasure, if you're struggling give me a call and I can post you any bits you need.

 

[Gavin_d]

Will do. Will bear you in mind for my home stuff to. Local weld suply guy is just a salesman and knows jack #*%€ about welding.

 

[Jim Davey]

That's where I win over the average rep, I use what I sell on a daily basis.