water/air tight welds

[bennyy]

I am welding various things at the moment, all tube and all about 1.5mm-1.8mm think. I have a Clarke 130en turbo welder, on lowest setting I don't get much penetration, the weld sits high and looks untidy, on the next setting up, I have to pulse it otherwise I blow through, the penetration is acceptable. The next setting up, I have to leave a good second or so between each pulse, the welds sit real flush, but I seem to get little pin holes in the centre of each one? All on the same wire speed (about 8) which would be the easiest technique to keep it air tight?

I do not do a lot of welding on anything less than 2mm thick.

 

[bennyy]

Also using 0.6mm wire if it makes any difference

 

[Piero]

Thats the thing with welders that have swtich settings,
The amps jump from one setting to the other, a reostat type amp setting if the way forward.
alas you dont see them in many mig sets.

You should, with a little bit of tinkering get away with it though,
Right, so on the lowest setting there is no enough amps, on the next setting there is to many.

things to do, change to a small diamitor wire (as said above) the smaller the wire, the less amps needed to melt it.

move the torch faster, helps with heat build up.

use some thing to take the heat away, be inventive.

a good methord I adopt is look very closley at the weld pool, start your weld, look at the weld pool as HEAT, as soon as the heat gets a little hot, stop.
dont move the torch, with in seconds she starts to cool down, start as soon as this happens.
DONT let it cool down to much.

a little pratice with this methord can really work on migs with amp setting issues.

good luck

 

[slimjim]

What gas are you using, and what wire?

Sounds like your running CO2 or gasless,

You will find it easier if you run Argon/CO2 mix, and replace the carp earth lead on the welder, also are you sure you are using the switches on the front correctly, as it's not clear what the 1 and 2, A and B switching system does, so you could be putting it on a higher setting than you think,

I have a portamig with 12 settings, but also a clarke with only 7, starts at 30 amp and goes up to 250 amp, and it works fine, welding from 0.8 to 8mm metal,

 

[bennyy]

I am using argon/co2 mix.

Yeah the power settings going from lowest>highest

1+min - too little penetration

2+min - can do about 1"runs before it blows through, pulse welding doesn't seem to penetrate as much as I like.

1+max-pulse welding, penetration is good but I get pin holes in the centre.

2+max not even going to try.

I just need to figure out which technique is best and then practice.

 

[dai]

do the pulse techneque then do a second run over the first weld
the first weld will suport the second

 

[keith19]

This sounds your best setting, but you'll have to get rid of the pinholes, if that's what they are:
1+max-pulse welding, penetration is good but I get pin holes in the centre.

Is the pipe clean, no galv, etc? No contamination inside? Could try it with the gas turned up a bit if there's no contamination.

This guy gets good penetration on thin pipe, take a look:
http://www.youtube.com/watch?v=JohBHzhOyPg

 

[bennyy]

Mine is the exact sane, they look neat but I need to figure how to avoid the pin holes, its just,a single hole where I arced up and stopped, yes it clean stainless, gnu do not have a gauge, I have always set it up so I can just hear it,bin,also welding in doors.

 

[sonamor]

What setting are you using on your wire speed, amp control knob?

 

[Wozzaaah]

We seem to have a lack of info in this thread, I'm assuming by what you're saying you're using mild steel wire and disposable ar/co2 to weld stainless steel?

 

[bennyy]

Yes that's right, I'm using about wire speed 7, I prefer using a fairly high wire speed wherever possible.

Mild steel 0.6 wire, stainless steel pipe/tube, at/co2 disposable bottles.

 

[backpurge]

If you are welding stainless you want to be using stainless wire and argon with a maximum of 2.5% CO2 in it, a high wire speed can also give you problems, you need to use a wire feed speed that is appropriate to the voltage you are using. Too much wire and the weld will be far too cold with excess spatter and lack of fusion/penetration

 

[dannyp]

welding stainless with mild steel wire is doable but never optimal

the weld will rust, also he back of the weld will be messy if you go for full penetraion unless you back purge it

i would have thought tho you chould get around the lack of penitraion / blowing holes with technique. at work i use a 480 amp machene with 24 voltage settings but its not like it needs that meany i find that changeing tecnique saves me haveing to walk across the shop **** about with the settings.

speed of travel, wire speed and torch angel . massivly effect how thins behave

 

[Wozzaaah]

Yes that's right, I'm using about wire speed 7, I prefer using a fairly high wire speed wherever possible.

Mild steel 0.6 wire, stainless steel pipe/tube, at/co2 disposable bottles.

For future reference, that's the sort of info you should put in your opening post, it will help you get better answers, as you can now see.

 

[Liebherr Welder]

Point the wire in the middles of the gap and just flick from side to side fairly fast and if you look closely you should see a key hole sort of shape so that you know it it penetrating and getting a nice root