(G) Sil rust - How bad is bad?

After successfully changing the engine mount I found this lovely patch of rust. How bad is bad and what’s the possible solutions to this?

All I’ve managed to find so far is

That is not bad at all, mine was like shredded wheat for about 3 inches in each direction. A patch will suffice, remember to weld all round the patch, no stitches allowed.

Cheers

D

More details on patches? Something i can buy or is it a case of making? My mate is good with a welder, but i'm not sure if i trust him with this.....

Oh, would this be a MOT fail?

Probably

1. Get a piece of metal plate the right size
2. Hammer said piece of metal to match any contours
3. Weld it in, leaving no gaps, i.e. full seam weld

HTH

Thought there might of been a more technical method

I forgot to say derust the sills before welding

I would prpbably start with,

Grind hole back to good metal,

then,

Make a patch etc.

then

Grind down welds and paint

Cheers

D

It was reasons like this that my 899cc is lying in my garage being stripped of anything saleable...

Cost of repair was silly and car was dirt cheap. That and I had an idea...

And I wonder what that would be Tom

Not really, you can buy a full sill but thats laughably stupid. What has been suggested is the best method and basically the only one. That woudlnt fail an MOT as its isolated enough at the inute, but when it spreads upwards and worse, further under, it compromises strength even more so. Basically cut out the rust, and while its got the hole in the sill that you have removed, spray some preservative down the sill if possible, like waxoyl or even old engine oil also de-rust the surrounding area. Tidy the edges and weld a plate it, then smooth it back and when cool smoth over with primer if you wish to. If not then just paitn over with preservative paint - good as new (lol nearly anyway)

Excellent. I'll get onto it soonish. Depends how much other stuff to get it through it's MOT.