Welding Tips and Tricks

Hi guys, recently when I start a bead, I get porosity at the start of it, like if the gas wasn't flowing for the first 1-2 seconds.
After that, everything goes like a charm, with a solid, pretty bead.
Obviously tack welds are awful...
Gas flow is about 14-15 lpm (a little more than 30cfh), I've tried going lower just in case I was creating too much turbolence, but it seems to get worse..

I've cleaned the nozzle, checked the hose and no, the gas bottle is not empty (they always say that... I mean, do they really think we are so dumb?!?! )

The only thing that comes to my mind is that some time ago I changed the hose with a smaller diameter one... could it be the cause? (I don't remember exactly if it started doing this after I replaced the hose or if the two things are completely scorrelated)

Any idea?

That'll happen when the tipped is recessed to far back in the nozzel. I cut my nozzels down so my tip is flush. Jody posted that tip and it works.

I've tried with the tip recessed, the tip flush and the tip slightly out (about 1mm)... always porosity...

Your problem is probably lack of gas coverage. So you could turn uo your gas, or i like to run the gas for 2-3 seconds before i pres down far enough to start the wire reel turning, but this may or may not be possible with your setup. Anyway, if you can increase you gas flow or pre wled gas flow, that should do the trick.

hope this helps,

-Rick

I do not have pre-flow, and the torch is quite sensible, so that when I press the button both gas and wire start.
For the moment I'm running a short bead on a piece of scrap, and then quickly move onto the piece, but that's not a viable solution long term.
I'll try to up the gas flow, however!

The only thing that comes to my mind is that some time ago I changed the hose with a smaller diameter one... could it be the cause? (I don't remember exactly if it started doing this after I replaced the hose or if the two things are completely scorrelated)

Couldnt hurt to try a bigger diameter hose. If your lowering the surface area inside the hose, your going to increase the pressure. Id replace it with the original diameter hose, and make sure you dont have any crap in side the hose or any of the fittings slowing up the flow.