I apologise in advance for the poor quality- and slight paucity- of photos in this post. I have a screw on macro lens and a ringflash for my 450d but I wasn't going to take that into the garage with a MIG welder, so they were all taken on my £60 Technika compact. I probably should have taken a few more photos, but when you're sweating, fretting and swearing, taking photos is a secondary thought.
Anyway, to set the scene: shortly after its last MOT, the cheapo pattern backbox on my mum's Clio diesel rusted away and broke where the link pipe meets the silencer.
I first of all tried to fix it with a beer can, some Jubilee clips and a load of silicone sealant. That lasted about 30 minutes. A couple of months ago I replaced the beer can with a baked bean tin on the basis that it would be stronger (as shown in the pic above). That also lasted....30 minutes.
About a year ago Aldi sold a gasless MIG welder for £99.99. At the time I had an old Maestro outside the house with a rusty bulkhead that wouldn't have taken much welding to get through the MOT. Nice, I thought, but I really want a Gas capable welder. Aldi didn't sell one and then the Maestro's tax ran out so it got scrapped (probably for the best). Fast forward to last month though and they had a Gas/No Gas welder for £139.99.
Right now I have a Peugeot 106 Rallye outside my house. It also doesn't have an MOT, but not because it's rusty. Nevertheless I couldn't resist and the welder went in the trolley.
So anyway, the Clio's MOT was due and I thought I could at least get some use out of my impulse purchase welder. So I dragged it round my mum's. Parked the Clio on the big high kerb outside her house with a brick under the NSR wheel, crawled underneath, and the two bits of exhaust came off easily enough.
Now, to weld properly you really need clean metal to weld to. The best idea would be to clamp the pipe in a vice and use a decent Angle grinder/cutter. I just grabbed the pipe in one hand, and in the other:
...my £12.99 eBuyer angle grinder with a grinding disc from Aldi. Result:
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Smooth! The silencer got the same treatment:
So then I got the welder out of its box and set about studying the instructions. I eventually got the wire installed and feeding out of the torch; MIG wire is springy stuff with a real penchant for unwinding itself all over the place
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It's best to firmly clamp your work pieces together at the correct angle. I had no clamps though and my best guess at the correct angle was that when the silencer was horizontal, the end of the link pipe should be too. So I just held it in the right place:
I should mention that while peering down the link pipe I'd noticed another small rust hole and ground it off so I could fill it with weld. I thought I took a picture of this, turned out I didn't. So anyway, after my first attempt with the welder, this was the result:
Blurry pic sorry. Anyway you can see that the hole is not filled with weld- in fact I'd burned an even bigger hole. The pipe is also not tack welded to the silencer as I had hoped.