A mate of mine has stitched me up with a repair job on the floor pan his trucks cab. Now I haven't welded anything thinner than 3mm for at least 20 years. Question: what are the MOT testers looking for_ are they looking a seamless weld or can I getaway with spot welds ? The problem I have is that this job came halfway through, and while he's cut out most of the rust he has not gone far enough in my opinion and welding it is proving problematic. The good metal is welding fine but the thinner stuff is blowing through as soon as you touch it.
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Bill Edwards
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If you replace a panel that was originally held in place with spot welds then you can do the same.
If you cut out a patch (even if it's of the same spot welded panel) then the repair must be fully seam welded - yes, even if the surrounding metal is only held in with spots!
If you cut out a patch (even if it's of the same spot welded panel) then the repair must be fully seam welded - yes, even if the surrounding metal is only held in with spots!
I believe you now have to have continuous weld where the metal was solid before. So if a section has been cut out then I would say you have to weld all the way around.
If still burning through then that would suggest not cutting back the bad metal enough.
I stand to be corrected but that is what I believe.
Adrian
To slow
If still burning through then that would suggest not cutting back the bad metal enough.
I stand to be corrected but that is what I believe.
Adrian
To slow
WorkshopChris
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As far as i am aware as long as the repaired section is joined with continuous weld your are ok.
That can be a series of joined tacks (where you pull trigger weld allow to cool weld cool weld and repeat) and does not need to be what would be considered a continuous run of weld as you would see when welding structural steel.
That can be a series of joined tacks (where you pull trigger weld allow to cool weld cool weld and repeat) and does not need to be what would be considered a continuous run of weld as you would see when welding structural steel.
Bill Edwards
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Yes, the weld has to be continuous metal but that's not to say a continuous run, a series of overlapping tacks will do.
If the metal you're patching onto is too think to weld properly then it's not been cut far enough back. If you weld it using overlapped tacks then it'll pass but obviously won't last long, vs cutting further until good metal is found to make a lasting repair. Depends on the intended use of the vehicle, i.e whether it's get it through a final MOT or a long term car and of course that you're doing it for free
If the metal you're patching onto is too think to weld properly then it's not been cut far enough back. If you weld it using overlapped tacks then it'll pass but obviously won't last long, vs cutting further until good metal is found to make a lasting repair. Depends on the intended use of the vehicle, i.e whether it's get it through a final MOT or a long term car and of course that you're doing it for free
Wendelspanswick
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Sometimes it makes more sense to drill out a complete spotwelded panel and replace it rather than having to seam weld a repair patch into it, plus you don't have to cope with the distortion caused.
addjunkie
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Sometimes it pays...to say sorry im busy, but i can send you some links to you tube videos, so you can learn to do it yourself.
I will never weld a car again, a 5 minute patch for a mate turned in to days under a rotton car.....that was 20 years ago, and my opinion hasnt changed, though I have been asked.
I will never weld a car again, a 5 minute patch for a mate turned in to days under a rotton car.....that was 20 years ago, and my opinion hasnt changed, though I have been asked.
I'm not too old to learn
Bill Edwards
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That's vehicle welding for you - a 50 pence piece sized hole can be two foot of rot to be cut out by the time it's done.
Check out my thread on a Mercedes wiring loom repair after patching a small hole and setting fire to the wiring!
First (AND LAST!) time I do any MOT welding.
As to never having a complaint from the MOT chap that's almost akin to saying you've never had a corpse complain about their treatment in a funeral parlor. MOT's just require the whole patch to be continuously joined but can't really fail it for the welding no matter how bad it is, nor can they scrape off any underseal to actually look at it closely. Glue the patch on with anything you like, apply silicone sealant to the edges then give it a health dose of underseal type stuff and it pretty much has to pass.
Check out my thread on a Mercedes wiring loom repair after patching a small hole and setting fire to the wiring!
First (AND LAST!
) time I do any MOT welding.As to never having a complaint from the MOT chap that's almost akin to saying you've never had a corpse complain about their treatment in a funeral parlor. MOT's just require the whole patch to be continuously joined but can't really fail it for the welding no matter how bad it is, nor can they scrape off any underseal to actually look at it closely. Glue the patch on with anything you like, apply silicone sealant to the edges then give it a health dose of underseal type stuff and it pretty much has to pass.
Well, it's done... All I am going to say is that I hope Bill Edwards post is correct in that it doesn't matter what it looks like.
Never, never, never again. I have renewed respect for you chaps that weld this stuff correctly. Mine looks like the pigeons have been busy - very busy. Now for copious amounts of silicon and underseal.......
Never, never, never again. I have renewed respect for you chaps that weld this stuff correctly. Mine looks like the pigeons have been busy - very busy. Now for copious amounts of silicon and underseal.......Bill Edwards
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Yep, it's not pleasant work is it!
