mot and question

[bis13]

just been to one of the scariest mots ive ever seen , the testers didnt bugger about with little hammers and strange tools ive never seen used before! i then got the result that my little 79 deville was mechanically fault free which made me very happy , there is less stress at childbirth for me ......doesnt look to good for my polski though as i found a nasty patch on an outer sill and just had to bash it in with a hammer ....i now need to cut out the old sill and weld in a new one. am i right in thinking if i remove the complete sill i am allowed to spot weld along the top edges and tack in the bottom ? this being as its a complete sill ? whereas if i just cut out the rust and aplly new steel just to that area it must be a continuous weld? which will mean a big load of heat going into the car?

[toz]

Hi mick,

Even if you fit the complete section you will still need to mig it at the joins which will involve alot of heat,i would fit the hole section if i was you as there is alot of old waxoil that easily catches fire if you make a plate(in the inner sill).it really is up to you but at least you wont have to make more patches in the future.
just make sure what ever you do get someone to fire watch,ie give your kid a bag of sweets and a fire extinquisher lol

[michaelodonnell500]

You would get away with spot welding in a mot. You can get away with alot if you cover the seams in seam sealer as they can't see the repair and as long as it's solid they can't complain.
That said, welding a sill onto a sill will leave a moisture trap between the 2 skins which will rot quicker than a descent repair would. On top tof Toz's point about heat distortion which then means adding a load of car filler to finish it off.
I used to do fire watching for my Dad when he was welding up peoples cars. I never got a bag of sweets out of it!