Argon/CO2 mix for MIG

Depends how infrequent, and how much you'll be using. I haven't found many options for argoshield, it's either disposables or BOC around here. BOC doesn't work out cheap for the odd bit of welding because of the bottle hire, but chuck aways are bloody expensive if you've got more than a foot of weld to do, IMO.

I use plain CO2, because I bought a 5kg bottle for 50 quid outright, and it's 15 quid for a refill on an exchange basis, so a little more expensive than BOC for the exchange, but compared to the bottle rental with the amount I weld it's actually a hell of a lot cheaper. Trouble is the place I get it from doesn't offer any other gases, but CO2 is OK, if not great.

practically speaking, buy a boc bottle from a dodgy trader, find someone who will get refills for you.

hiring a full size boc argoshield is 70 pounds a year, the refill is about

38 pounds.

air products are slightly cheaper

first find your bottle, scrap merchants are a good place to start.

mrcheerful

Dave, I've used the disposables for several years. I am also an infrequent user. When I initially bought the MIG kit (after spending so much on contract bottle fees with BOC) I thought the disposables were far too short lived and was punting around for an alternative. A fellow hobby restorer gave me some advice I've been very grateful for. "Turn down the gas until it is a just discernable hiss when the trigger is squeezed (machine 'off')"

The bottle now seems to last for ages and ages. He explained that the gas has to merely shield the work so providing you are not working in a howling gale this low setting is adequate. My welds seem fine and have stood the test of time.

Hope this is of some help........ Regards Gee

Bite the bullet and hire the bottle. It's not cheap though.

I always found that the disposables weren't too expensive as a way of buying gas (by volume), but that their sealing wasn't too reliable. If you used a fraction of a bottle, then came back to it a few months later, the bottle would have leaked and would now be empty.

Yup. I'm using the second lowest power setting on a Migmate Turbo 130. I can't seem to get it to strike on the lowest setting.

The trouble is I know how it should be as I used to MIG weld many years ago, but that was with pro equipment. And I can't remember having any of these problems.

Yes.

I find adjusting the wire feed speed on the SIP is a pain - it stalls on the minimum setting and a tiny movement of the control makes it whizz out. I bought it as the recommended one in a Practical Classics test of several.

I'll practice again with it set to minimum power and less gas flow which set as they recommend is costing a fortune. I've got through 4 bottles just practising - I doubt much more than a metre or so of welding in total.

There's something funny here. My cheapo Mig uses the disposable bottles at around 1 bottle per whole reel, even with the gas regulator wide open. Mind you, I find it very difficult to get a clean weld, and often end up overcooking the joint just so I know it's solid, then end up grinding to finish.

Maybe my kit has always had some sort of blockage, or restriction due to poor design.

The chap replacing all the old CO2 fire extinguishers with new ones in my place of work gave me a couple as they'd have gone into a skip otherwise. The screw thread holding on the extinguisher cone just happens to be the same as that on your average regulator. The method apparently, is to fit the regulator then clamp the trigger mechanism in its open position. I haven't used them yet as I still have most of a large bottle to finish. It seems that Fire Protection specialists quite often dispose of old, but perfectly sound CO2 extinguishers, so if you have in the area...

Sounds like the end of the wire might be oxydised. If so it's not actually making contact. Try snipping the end of the wire. While I was learning, I found that helped a lot. The lower the power, the better the contact needed to start arcing. Once it arcs the melting wire easily maintains good contact.

On the Clarke, the minimum feed speed is too low for the thinnest sheet. I would assume your SIP is the same.

The Clarke speed control knob can rotate about 270 degrees, but in practice I can only use the range between about 30-80 degrees. Either side of those figures, and it's too fast or too slow for the minimum and maximum power settings. Within that 50 degree range though, the wire feed speed can be adjusted very progressively and accurately.

If your SIP can't give a smooth progressive transistion from slow to fast, even if that means fairly small movements of the speed knob, I'd suggest there is something wrong with it. The speed control shouldn't be too sensitive to easily achieve a suitable speed setting.

If it's the test I recall, it was many years ago. Maybe your m/c has become sticky through lack of use. :-)

What!!! I think I can confidently say your gas setting is definitely, indubitably, and most certainly too high.:-)

Set the gas regulator on the bottle so you can only just hear the gas coming out. If it's too low it'll be obvious. You'll just get a crappy burnt mess, and you'll need to increase it slightly. Also check the valve on the gun itself. If that is leaking, it could be contributing to the excessive gas consumption.

A final thaught. I found when learning, that the inside of the gas nozzle on the gun rapidly became gunged up with lumps of crap, from the splattering it got from my early attempts with the wrong settings etc. Making sure that the inside is reasonably clear should help to give a smoother gas flow, and reduce the amount of gas needed to maintain the shield.

Email me if you feel we're going on too much for the n/g. Mike.

Can you hear the gas hissing when you pull the trigger? Mine doesn't need to be switched on for this.

I'm going to check all the pipework for leaks.

Or perhaps the wire is slightly tangled on the reel. I'd suggest opening/removing the side of the welder and watching how the wire feeds with the speed turned quite low. If the reel was allowed to loosen when it was first put on the machine, the wire could have crossed itself and will never feed smoothly. Incidentally, I find that large reels feed a lot more smoothly than small ones with my Clarke.

Another tip is to make sure that you always have something to rest your hand on as you weld. Ideally, it should be in a position that allows your hand to pivot, moving the torch through 3 or 4 inches along the area to be joined. This is to stop your hand waving around rather than to take its weight and can make world of difference to your results. A welding clamp off to one side is often sufficient.

So why did you buy a SIP ? They were slagged off in front of you, but you knew better. Now _after_ you've bought one, you find they're as bad as you were told.

Oh, and your gas valve is stuck. That's the other common fault.

Yes, and quite a healthy hiss I think ;-)

If I leave the cylinder regulator open the system does leak down, so the trigger mechanism must be a bit cheap / naff. I always make sure that the regulator is turned off at the end of each session. I failed to do this once and lost a complete cylinder over a few days of non-use.

I'd bought it *before* some slagged it off. And you might be happy accepting a total stranger's word as gospel on something over a mag like Practical Classics, but I'm not. Others were also happy to recommend it.

On investigation, it appears to work in reverse.

Is yours a Migmate?

The valve on mine appears to work in reverse. Fully anti clockwise it shuts off the gas - fully clockwise it's full (or nearly) full on. The opposite of what both the handbook and arrows on the valve say.

A better reason than I had to buy my Clarke 100E. The Pillar eng'g rep (Now Buck & Hickman) offered it to me because a customer had tried it and given it back, so technically it was s/h, but AFAIC it was new. Having only had a few hrs of use at most. He'd just picked it up, and it was in the back of his car. He offered it to me for £100. The list price at the time was £147, so I snapped it up. Came with an almost full bottle of gas as well, which wasn't included with a new m/c. Up until then, I'd been doing all my welding with a SIP arc welder, but the MIG was more suitable for many of the smaller jobs I was doing at the time.

You might be interested. I recently baught an automatically dimming welding helmet. £39 on ebay, inc P&P. The same as this one:-

bit of kit. Works a treat. Probably not as well made as the onescosting anything up to £200, but who cares, as long as it does the job.Far easier than holding the provided shield, or even a plain flip up helmet.I'm not on commision BTW.:-)I just think they're good value.Mike.

For what it is worth I always disconnect my regulator (unscrew it completely) between sessions. As already stated in earlier post, my disposables last well, not sure about consumption but I don't think I use more than say 2 disposables per reel of wire although I've been surprised how much welding I get from a reel. Before I bought my set I was told I'd need to use the "Big" reels but found this not so. Regards Gee

I got the Migmate new off Ebay, for about the cheapest I could find it anywhere, but *without* VAT. And the carriage was good value too. IIRC,

140 total - sent direct from the 'factory'. About a couple of years ago, but never got round to using it.

I've already got one. ;-) Just dunno how anyone manages with the ordinary type. Skill, I suppose.

Definitely skill, says he after welding for years without one. Nah. My welds still don't look as neat as those done by a professional, but I'd guarantee that they're as strong. Mine just need a little more fettling with an angle grinder.:-) Mike.

PC did a test of pretty well all similarly priced welders, and it came out top.

Of course it's not as good as a pro one, but I have the problem that it has to be carried up and down stairs, as I don't have a garage to keep it in. So weight and portability is a crucial factor - as was cost.

I'm using a large reel. I'm going to investigate why the regulator works in reverse. It appears at the moment to be using the bottle valve as the control mechanism - and doesn't cut off the gas when 'closed'.