Gas won't flow - driving me to despair!

[Surfwagon]

Hi, got a cheap Ferm 150/1 - which has come in handy as I need to weld the sills on my new surfing campervan conversion. Someone else has kindly let me work under cover on their farm for a few days, but Im running out of time fast!
After an hour's use (plug welding) - the gasflow ceased.
After I added a fresh bottle of co2 - I could only get occassional 'gasps' of gas at the gun.
That day's work ruined - I spent several hours next day getting hold of a new regulator.
Next day - same problem! The tube isn't blocked - I can blow through it when the trigger is pulled - and hear it hiss through at the tip - but the gas flow appears completely random: sometimes a random setting on the reg works for a very short while - then disappears again!
I even emptied a brand new mini-bottle (god knows how) just trying to get it to reach the gun.

Could it be the little valve switch in the handset gun failing? Are spare guns available?
In short - anyone experienced this before?

 

[slim_boy_fat]

These disposable bottles are rubbish - it's not difficult to empty one by looking the wrong way at it.

 

[Fintray]

If you are that short of time you should just get flux cored wire, it's not so good as having gas but if you want a bigger bottle (that will last far far longer than the disposable ones) you will need the bottle, a regulator and some way to convert from the larger hose to the small hose.

 

[Rocketman]

Yep had that problem with my Clarke pro 90 when I fitted a Sealey regulator with pressure gauge. It would not work or it chucked out all the gas within seconds.

Put the Clarke back on with no pressure gauge and it fixed all the problems.

 

[Surfwagon]

Yep had that problem with my Clarke pro 90 when I fitted a Sealey regulator with pressure gauge. It would not work or it chucked out all the gas within seconds.

Put the Clarke back on with no pressure gauge and it fixed all the problems.

Thanks for the replies, folks.
The reg I bought does look identical in every way to the one that was on originally - but as I said, it appears to be completely haywire.
Nyaaargh!

 

[the snooper]

You only get 10 minutes solid welding Time from disposable bottles and plug welding who can say, it depends if you waste any before arcing up ie squeeze trigger slightly for second or so before welding, they are too expensive to use if doing any amount of work

 

[Surfwagon]

Flux core?
That sounds interesting. Does the slag come off cleanly? Don't want to be whacking 1mm steel with a chipping hammer!
Will it handle that gauge steel ok? I hear it runs a bit hotter than gas?

 

[outofthefire]

You'll struggle welding thin steel with flux core and as far as unless your welders designed to use it (I believe that you have to reverse the polarity to use it) it won't work properly anyway.

 

[Bill Edwards]

How much welding have you got to do?
Few people would recommend flux core wire for anything thin.

The best stuff is a mix of argon and co2 (95% argon). Look up the BOC Volkzone offer on here to see the price, it's a very good deal and you get a huge amount of gas. If you've a big project it is well worth it.
If doing a smaller job then do a search for rent free gas, it's less expensive than the disposable bottles. But if you go through much the BOC deal is better.

 

[Surfwagon]

I've seen posts from someone who's used flux core on car bodies for a long time...
My problem with gas is that I'm mid job - and the gas won't regulate and flow through my machine. In fact it also seems to have an internal leak that's emptied a bottle.
Can anyone confirm that I need to reverse polarity to use flux core?

 

[sparkysy]

Yes. You do need to be earth posi when using flux core you will also need different size ends as it is bigger diameter 0.9 if I recall! It's on the tutorial bit on here somewhere. Can't find the linky!

 

[outofthefire]

you'll also probably need a new feed roller as well, because the grooves on yours are most likely .8 and .6.

 

[Surfwagon]

Thanks all.
Just one more point, anyone who has welded car bodywork? - before I commit myself to buying flux core tomorrow?
Can you PLUG WELD 1mm sheets together with flux core?
The technique I've always used (with co2) involved short bursts to prevent burn through. The slag presumably won't allow this, right?
Or can it be cleaned between runs?

 

[outofthefire]

before I commit myself to buying flux core tomorrow?
Can you PLUG WELD 1mm sheets together with flux core?

Have you you not read the previous answers with regard to flux core? what the point of coming here and asking for advice then ignoring it completely?

 

[Surfwagon]

Have you you not read the previous answers with regard to flux core? what the point of coming here and asking for advice then ignoring it completely?

Erm, because I've read extensively on this - and lots of people DO use flux core on light steel, and many use it pos electrode without probs - despite your claim that you "think" I can't do the same.
I've also bought .8 wire, so your claim that I'll need to change rollers doesn't quite stack up either.
I've tested some today - there's no spatter. It's not as nice as gas, but it's nicer than not getting the job done at all - which is what I'm up against here.

 

[Surfwagon]

If you are that short of time you should just get flux cored wire

Thanks mate for that advice - you saved the job! (van sills) I have considerable Mig experience - but had never heard of gasless.
Just the ticket - once I'd found a good wire: SIF! The generic stuff is TERRIBLE.

 

[Fintray]

Glad to hear you got your job finished, gasless never seems as good but getting wire from a decent manufacturer makes a big difference, well it's one less thing to worry about......