No Gas conversion for MIG.
Discussion
I've just recommisioned my old Cebora MIG rig, but I don't have access to the large type gas bottle I used to use. I've gone over to the disposable bottles, but only managed a small repair before the bottle ran out. I hadn't realised just how quickly they would be used up. 
I wondered if it is possible to just swop the welding wire for the type with a flux core? Are there any mods I need to do for this (I seem to recall that the polarity has to be changed)?
Here is the welder:
This is the section I welded on a single bottle (plus some practice welding on scrap as I haven' welded for about 15 years), the 3 sides of this plate and various plug welds to replace the original spot welds:
I wondered if it is possible to just swop the welding wire for the type with a flux core? Are there any mods I need to do for this (I seem to recall that the polarity has to be changed)?Here is the welder:
This is the section I welded on a single bottle (plus some practice welding on scrap as I haven' welded for about 15 years), the 3 sides of this plate and various plug welds to replace the original spot welds:
Polarity has to be swapped for flux cored wire - this might be a slightly tricky if your welder doesn't have the facility to do this. Gassless wire makes a lot of smoke, covers the area of the weld in spatter and a white deposit and the welds themselves are not quite as neat as using gas IME. You can still make a decent weld with them, but it's more labour intensive to clean up afterwards, and the wire is quite expensive.
I'm a bit surprised at how quickly you ran out of gas though, I'm guessing it was a standard bottle (rather than the high capacity ones) but even so I wonder if you had the gas turned way too high or your machine has a leak?
FWIW I built most of a Locost chassis on a single high capacity disposable CO2 bottle with a Clarke 105EN MIG.
I'm a bit surprised at how quickly you ran out of gas though, I'm guessing it was a standard bottle (rather than the high capacity ones) but even so I wonder if you had the gas turned way too high or your machine has a leak?
FWIW I built most of a Locost chassis on a single high capacity disposable CO2 bottle with a Clarke 105EN MIG.
Thanks for the feedback. I may well have had it turned up too high. The bottles are just from Halfords as they were convienient and dearer in the BOC shop I looked at. I did check for leaks and it seemed fine. At this rate I'll probably get through the other two bottles I have putting the wing & wing rail and strut strengthener plate back on. Then I need to repeat for the other side, so another three bottles. I guess £50 or so for them isn't so bad considering what I would pay to have someone else do it, so not the end of the world as I hope not to need it after this job hence why I went down the disposable bottle route.
Another question: What do you do with the empty bottles? Can't just put them in the bin, but not sure what they would make of them at the dump...
Another question: What do you do with the empty bottles? Can't just put them in the bin, but not sure what they would make of them at the dump...
It's a steel bottle so there should be no problems putting them in the scrap metal skip at you recycling centre.
The higher capacity bottles are available from Machine Mart if you have one near you, otherwise maybe consider Hobbyweld who do larger refillable cylinders with no rental, though you pay a deposit on the cylinder itself.
The higher capacity bottles are available from Machine Mart if you have one near you, otherwise maybe consider Hobbyweld who do larger refillable cylinders with no rental, though you pay a deposit on the cylinder itself.
Edited by Mr2Mike on Sunday 29th April 10:11
Thanks Mike. Might have a little weld today as I received my new auto darkening mask yesterday. 
I'll try lowering the pressure on the regulator to see if I can get more time out of it on bottle number two. Probably worth spending 5 minutes on some scrap metal to see how low I can set it before the gas doesn't do it's job.
I'll try lowering the pressure on the regulator to see if I can get more time out of it on bottle number two. Probably worth spending 5 minutes on some scrap metal to see how low I can set it before the gas doesn't do it's job.The new mask is great, can see where I'm welding much easier than before. I must have had the pressure set a bit too high on the first bottle as I found I could set it much lower (the needle barely comes off the zero when in use) and it still protects the weld. Hopefully the second bottle will last longer than the first.
However, I managed to injure myself today with the angle grinder using a wire brush attachment: It caught on an edge and it was thrown back at my face, catching my mouth and surrounding area. Gave the Mrs a fright when I went back into the house I can say...typically I would have been wearing a face mask which would have protected me (I had goggles and ear defenders on) but didn't as this was the last quick clean up before welding. Really fed up as I've blackened the odd fingernail and got plenty of cuts and bruises over the years of DIY, but this is quite nasty.
Guess the RS might be left alone for a few days until this heals up a bit...
However, I managed to injure myself today with the angle grinder using a wire brush attachment: It caught on an edge and it was thrown back at my face, catching my mouth and surrounding area. Gave the Mrs a fright when I went back into the house I can say...typically I would have been wearing a face mask which would have protected me (I had goggles and ear defenders on) but didn't as this was the last quick clean up before welding. Really fed up as I've blackened the odd fingernail and got plenty of cuts and bruises over the years of DIY, but this is quite nasty.
Guess the RS might be left alone for a few days until this heals up a bit...
Ouch, that could have been really nasty Angle grinders are bloody dangerous bits of kit really, whether fitted with wire wheels or grinding/cutting discs. FWIW I find the full face shields much better than wearing safety goggles - more protection and better vision (don't steam up like goggles do).
Angle grinders are bloody dangerous bits of kit really, whether fitted with wire wheels or grinding/cutting discs. FWIW I find the full face shields much better than wearing safety goggles - more protection and better vision (don't steam up like goggles do).Cheers for the comments...spent today watching daytime TV (and Top Gear repeats, plus various 'Beetle Crisis' episodes on Quest channel ) and browsing the web feeling sorry for myself. I can't go to work as it's blooming sore, plus it just isn't a good look to visit customers with especially as I can't shave at the moment. Shame as the car is coming along quite well and I was just ready to tack the new wing rail in place...
) and browsing the web feeling sorry for myself. I can't go to work as it's blooming sore, plus it just isn't a good look to visit customers with especially as I can't shave at the moment. Shame as the car is coming along quite well and I was just ready to tack the new wing rail in place...It's been a while since I have used it, but I was using a Machine Mart Gasless Mig welder, and managed to do loads with it. All odds and sods of patching etc, as mentioned above it's not as neat .... think of it as the same as welding rods, but thinner and on a wire !
It does need a lot more cleaning up/grinding ...., and might be hard work if you are trying to do pretty welds on outer panels, but for the floor & chassis of the old 2cv I was using it on, it was fine.
You can certainly get it neater with practice, but as with all welding the cleanliness of the 2 pieces of metal to be welded were the critical factor.
It does need a lot more cleaning up/grinding ...., and might be hard work if you are trying to do pretty welds on outer panels, but for the floor & chassis of the old 2cv I was using it on, it was fine.
You can certainly get it neater with practice, but as with all welding the cleanliness of the 2 pieces of metal to be welded were the critical factor.
Flux cored wire is actually quite useful for welding outside if there is any wind, I welded the sills and rear arches on my Astra GTE 16v on my driveway using a gasless Clarke welder many years back and made a reasonably tidy job. However I only used gasless because I bought the welder for the job and it came with a reel of flux cored wire - after I switched to using gas I didn't swap back!
Much better thanks...any scar is currently hidden under a rather scruffy beard (with far too many grey whiskers for my liking!). Hope to get back on with the RS soon now I've got a full face/brow mask.
EDIT: You haven't got a relative called Dave have you? My parents had a friend called Dave Hutchinson that use to look after the RS when they owned it, they live not too far from you.
EDIT: You haven't got a relative called Dave have you? My parents had a friend called Dave Hutchinson that use to look after the RS when they owned it, they live not too far from you.
Edited by OldSkoolRS on Tuesday 15th May 17:56
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