MIG welding stainless steel

[uninformed]

welder = BOC (kempie) 250, 316ss wire 0.9mm dia, argon gas at about 17-18 on my gauge
it has 16 volatage settings, 4 coarse and 4 fine. i had it on 2 coarse and 3 fine. wire feed was about 3.7-4m/min

25 x 25 x 1.5mm shs stainless from commercial kitchen. cleaned all areas to be welded.

the problem i had was no matter how much i played around with the voltage or wire feed i coudn't get a decent weld.

below this setting it seemed to cold and sitting on the surface like bird poo.

at this setting i had to move very quickly to get an only ok weld.

yes they will hold but they looked liike shit

any tips, hints

cheers, serg

[4sum4]

what type of stainless are you welding

[ForceAnt]

well that is thin stainless ur trying to weld there with a mig..but i would back the wire off untill it goes barb barb barb and then increase it a little at a time untill it goes baaaaaarrrrrrb. its hard to say over the net but thats where experience comes in..

[AFeral]

Not sure if this will be of any help. I have found when welding stainless. That if welding too hot the wire can expand with the heat and jam in the tip causing the wire feed to be wrong. personaly I weld Stainless with a Tig welder as I find it easyer. Have you tryed polishing the weld once you have finished ? The opposing side of the weld also needs shield gas.

[GQPatrol V8]

welder = BOC (kempie) 250, 316ss wire 0.9mm dia, argon gas at about 17-18 on my gauge
it has 16 volatage settings, 4 coarse and 4 fine. i had it on 2 coarse and 3 fine. wire feed was about 3.7-4m/min

25 x 25 x 1.5mm shs stainless from commercial kitchen. cleaned all areas to be welded.

the problem i had was no matter how much i played around with the voltage or wire feed i coudn't get a decent weld.

below this setting it seemed to cold and sitting on the surface like bird poo.

at this setting i had to move very quickly to get an only ok weld.

yes they will hold but they looked liike shit

any tips, hints

cheers, serg

This is from a friend of mine Jack who speciallise in stainless steel and Aluminium welding.

1. Stainless steel needs a new liner in the torch, the copper coated steel wire that you use for steel welding leave copper residue inside the liner which acts like a brake on the stainless wire. The same goes if you are welding aluminium. Keep a seperate liner for each type of material you are welding, usually about $15 for a liner. I personally use different welders.

Next, Tip must be new, you get about 1.5 - 2 hours out of a tip. So that means a 15kg roll of mig wire will use about 10 tips. The gas that should be used Argon with a slight amount of oxygen (2%) and for aluminium 75% Argon & 25% Helium. The helium stops it smoking. Pure argon is too hot.

The welder should hum with no interuptions (continuos sound) and the wire feed adjusted accordinly up or down.

All the best , Hopefully this will help.
Uncle Jack

[uninformed]

Not sure if this will be of any help. I have found when welding stainless. That if welding too hot the wire can expand with the heat and jam in the tip causing the wire feed to be wrong. personaly I weld Stainless with a Tig welder as I find it easyer. Have you tryed polishing the weld once you have finished ? The opposing side of the weld also needs shield gas.

mig is the only welder i have and know how to use.

how do you get shielding gas on both sides of the weld?

cheers, serg

[4sum4]

Not sure if this will be of any help. I have found when welding stainless. That if welding too hot the wire can expand with the heat and jam in the tip causing the wire feed to be wrong. personaly I weld Stainless with a Tig welder as I find it easyer. Have you tryed polishing the weld once you have finished ? The opposing side of the weld also needs shield gas.

mig is the only welder i have and know how to use.

how do you get shielding gas on both sides of the weld?

cheers, serg

What sheilding gas are you using

[uninformed]

shielding gas is BOC welding grade argon.

ok so do you need to replace tips no matter what material welded?

cheers, Serg

ps 4sum4 how do i get to meet the girls in your avatar?

[AFeral]

I shield the oppsite side of the weld using a second bottle and regulator. With the hose pointing at the opposing side of the weld. Bit costly thats all.

[4sum4]

shielding gas is BOC welding grade argon.

ok so do you need to replace tips no matter what material welded?

cheers, Serg

ps 4sum4 how do i get to meet the girls in your avatar?

you shouldn`t need to change tips ,if your getting a bit of burn back let the wire stick out further this will also run a bit cooler,if you ever get stuck between 2 setting plug in a exstention lead

[sudso]

Not sure if this will be of any help. I have found when welding stainless. That if welding too hot the wire can expand with the heat and jam in the tip causing the wire feed to be wrong. personaly I weld Stainless with a Tig welder as I find it easyer. Have you tryed polishing the weld once you have finished ? The opposing side of the weld also needs shield gas.

mig is the only welder i have and know how to use.

how do you get shielding gas on both sides of the weld?

cheers, serg

You dont need shielding gas on both sides of the weld with mig. Tig yes.
Use a gas called Stainshield (BOC) for s/s mig welding
Syncropulse mig welders are best for stainless mig welding but with yours just start on some scrap s/s on the lowest amps and wire speed possible and work up from there. Stainless distorts like f**k with welding so minimal heat is best especially with 1.5mm sheet. I've welded this size s/s heaps with a mig but tigging is better with thin stuff......and prettier. s/s mig welds done with a standard mig will never look as good as tig.
Is your sheet sitting on a thick metal benchtop right under where you're welding it? If so it could be taking too much heat away at the lower amps.
Make sure you put plenty of tacks in place too before you start fully welding it, it'll minimise or eliminate misalignment along the joins caused by heat distortion as you weld.

[uninformed]

ok, i had it sitting on 6mm steel plate on a timber bench. its 25x25x1.5shs, not sheet.

so maybe placing it straight onto the timber will help.

earth was always directly to stainless and close to the weld.

so start with volatage on 1 coarse and 1 fine, very little wire speed and go up from there.

if the join is very good is it posible to melt these two together with very little wire. i've seen guys TIG with no rod when they are tacking up neat joints. maby like brazing

cheers, Serg

[bastard]

Try using .6 wire the wire you are using would be difficult for even an experienced welder,the wire you are using is nearly the same size as your steel there for you need nearly the same amount of heat to burn the wire as you do just to weld the job.And you do not nead to have gas blowing on the back,if you were welding something important like sprinkler systems or gas tanks you would fill the inside with gas but this generally only happens with tig welding.Tig welding stainless and mild steel is pretty easy and thats probably the best method for your job.cheers

[eliteforce32]

tig ur talking of when no filler rod is used is just called fussion, as said above will never achieve the same as low amp tig work, but i have have all three machines in my shed, in that case 2.5mm stainless ARK rods do the trick , i have had to make quite a few food grade pump bases, in sheet 3mm and above, so SHS will be the same, and with heat distortion due to peno' just stich section. i.e. start at far left go to far right etc, min distortion.

[uninformed]

i thought that .9mm wire was a bit thick, but it is the smallest that will fit the hub of my machine. or so i was told.

i only have a mig..... if i had a tig i would have used it.

it can't be impossible to produce a good weld with mig can it.

i guess its back to the shed and burn, burn, burn

cheers, serg

[bastard]

stop and start with about a one second delay and this should help you produce a nice even weld,once you get the temp write.

[bru21]

gas gas gas gas its all about the correct gas. I have welded heaps of s//steel in that thickness - including my trucks headers exhaust all 316, and 304 and choosing the correct gas for the thickness is essential. use a stainshield in the reccommended thickness range. last week i repaired a crack in 16mm thick s/steel and thought i would lash out on the correct thickness gas after consuming the rest of the thinner material gas. the difference is astounding. if you look at the ingreadients they are very different. look at boc.com.au under sheilding gasses

[uninformed]

cheers bru21

[ForceAnt]

Ive used argon as sheilding gas and works perfectly fine, it is actually next best to stainsheild. u can make it work with what u have got. it is just a matter of set up.

It aint all about the gas, if u cant weld, the right gas isnt going to help. U dont need a new liner, only if u want to get one. Alloy uses telfon liner also. I use straight argon for alloy and i dont have any smoking.

U can weld ur rhs with what u have got. just practice more.

[uninformed]

Ive used argon as sheilding gas and works perfectly fine, it is actually next best to stainsheild. u can make it work with what u have got. it is just a matter of set up.

It aint all about the gas, if u cant weld, the right gas isnt going to help. U dont need a new liner, only if u want to get one. Alloy uses telfon liner also. I use straight argon for alloy and i dont have any smoking.

U can weld ur rhs with what u have got. just practice more.

yep, i think this is it spot on.

i had a look at bocs shielding gases and the difference betwen stainshield and argon is 1.5% oxygen in the stainshield.

although this may make a difference i don't think it would be that much

cheers, Serg