Checking gas flow

[anto]

I have a big old mig welder i picked up cheap and now that my garage has a big enough power supply i was able to test it.
On all settings i cant get a decent weld. They all look like the welds are lacking shielding, they look like welds ive done when ive run out of gas.

I can hear gas coming out so obviously some is getting out but i have a feeling it isnt enough. The regulator is showing around 12lpm which is fine on my other invertor mig.

Any easy way of testing how much is coming out the gun?

Thanks,
Anton

 

[Robotstar5]

With a peashooter

 

[backpurge]

As above

 

[anto]

Thanks lads.
I bought a pea shooter and checked the gas flow.
Test Results;
Esab C160i - Regulator set at 20lpm, at the torch it was showing 15lpm
Big old problematic mig im testing - Reg set at 20lpm, at the torch 15lpm.

So the problem isn't the gas flow it seems.
Time to get the thinking cap on.

 

[Richard.]

Regs always tend to show higher than when measured at the business end but that I suppose is because your measuring 5 Mtrs down the line. Go by what your peashooter shows . If welding is effected and looks bad then check for leaks on the whole system. If it's sucking air in somewhere then it doesn't matter how good the flow rate is

 

[ajlelectronics]

If the welding is effected, surely he has no problem? ;-)

 

[WorkshopChris]

Make sure the o ring in the euro torch connector is ok. Had one that had perished and was dragging air into the gas mix. Took a while to track down was welding as if gas was off replaced o ring and welds were fine.

 

[anto]

Regs always tend to show higher than when measured at the business end but that I suppose is because your measuring 5 Mtrs down the line. Go by what your peashooter shows . If welding is effected and looks bad then check for leaks on the whole system. If it's sucking air in somewhere then it doesn't matter how good the flow rate is

Right il take a check of the whole line as the welds definitely look like they lack sufficient shielding.
I guessed there would be some loss of flow between reg and gun, hence the test with the known good welder.

If the welding is effected, surely he has no problem? ;-)

It is affected unfortunately.

Make sure the o ring in the euro torch connector is ok. Had one that had perished and was dragging air into the gas mix. Took a while to track down was welding as if gas was off replaced o ring and welds were fine.

Its an old machine so id say its probably due some service parts like o rings.

 

[Jim Davey]

What gas are you using?

 

[anto]

Only getting back to this now.
@Jim Davey just straight co2.
I took a look at the torch again and the O ring is completely gone.
Anyone know the size I need or were I can get one?

 

[Jim Davey]

Any welding shop should have them, if not drop me a PM.

 

[anto]

Thanks @Jim Davey there is an ESAB dealer up the road from my work I forgot all about him he should have something.

 

[anto]

Success!
A quick trip to Maplin (Esab guy didnt have anything) and I had a set of a few hundred O-rings of various sizes for £3.50.
It seems to have done the trick, although it wasn't the perfect seal it seems to be doing the job.

Thanks