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Discussion Starter #1
Just had a chat with the friendly garagiste...

MOT fail.

Rust on the RHF suspension mount - no close looking's yet been done (but certainly nothing had been noticed before), but this is apparently higher up and around the upper wishbone mount, not the driveshaft tunnel, which has already been plated...

The MOT man said it looked difficult to get to...
 

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Language please! :nono;

You are lucky it is not the LH side. :cheesy:
 

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Discussion Starter #3
RickyS said:
Language please! :nono;
That WAS the toned-down version...

You are lucky it is not the LH side. :cheesy:
I think we have different definitions of "lucky".

The friendly garagiste will be taking time off from flicking through holiday catalogues to take a proper look this pm.
 

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Discussion Starter #4
TooMany2cvs said:
The friendly garagiste will be taking time off from flicking through holiday catalogues to take a proper look this pm.
Turns out to be "just" the good old driveshaft tunnel...

I'm telling myself that's a good thing, as we knew it'd been plated anyway - and we knew it wasn't plated very well - but didn't realise quite HOW bad the job'd been last time. All that'd been done was to hack a bit of steel into roughly the right shape, then let an incontinent pigeon fly near the car.

That was it.
No attempt to cut out the old rotten steel.
No attempt to actually restore any strength.
Just a badly welded plate hiding it.

So... it's getting rapidly towards one completely rebuilt driveshaft tunnel. All new (and thicker) steel front, rear, left, right, bottom from behind the hole for the track rod, to in front of the front arm mount, to two-thirds of the way up the driveshaft hole. I've stopped in at the workshop and had a look this morning, and this is definitely to be filed under A Bit Of A Job, judging from the large pile of cardboard templates, the large pile of chopped out rot, and the blue tinge to the air...

At least it's not somewhere else that we'd missed completely. And at least the other side looks absolutely A1 still. Never bodged, doesn't need anything doing.

How odd.
 

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Be careful stitching thicker metal in - you should really stay at the same gauge (or at least close). When you insert thicker (stiffer) metal into an existing structure you can create a stress riser where the two meet (more significant than the weld itself) and can create fatigue stress cracks on the thinner (original) steel.
 

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Discussion Starter #6
SteveTheFolkie said:
Be careful stitching thicker metal in - you should really stay at the same gauge (or at least close). When you insert thicker (stiffer) metal into an existing structure you can create a stress riser where the two meet (more significant than the weld itself) and can create fatigue stress cracks on the thinner (original) steel.
Absolutely - but there's SOOO much new metal going in that I don't think it's likely to be an issue. I think it's going up from 1mm to 1.5mm, so not a huge step.

The guy doing it knows what he's doing... unlike the last chimp to have a go.
 

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Now, here's a question I've been wanting to ask for years......


When you plate up a box section, for example, how do you rustproof the hidden side of the new material?
 

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SteveTheFolkie said:
Be careful stitching thicker metal in - you should really stay at the same gauge (or at least close). When you insert thicker (stiffer) metal into an existing structure you can create a stress riser where the two meet (more significant than the weld itself) and can create fatigue stress cracks on the thinner (original) steel.
You sound like an engineer Steve, You wouldn't happen to be one? :cheesy:

In regards to rust proofing, I've never actually seen this particular area in person, but I would use somthing that was of low viscosity and see if I could spray it thorugh a small opening. There was this stuff called waxoyl that I read about, Seems they can spray it inside a door to prevent it from rusting and I would imagine you could do the same for this application.
 

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Discussion Starter #9
James Bond said:
When you plate up a box section, for example, how do you rustproof the hidden side of the new material?
<passes drill over>
You makes a nice neat 'ole to put rustproofing stuff in there through. Then you block it up with a grommet until you want to put more rustproofing stuff in.

Alternatively, you can paint the metal first with a weld-through primer.
 

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SteveTheFolkie said:
Be careful stitching thicker metal in - you should really stay at the same gauge (or at least close). When you insert thicker (stiffer) metal into an existing structure you can create a stress riser where the two meet (more significant than the weld itself) and can create fatigue stress cracks on the thinner (original) steel.
Meh, just add more metal. Its amazing there aren't more stress cracks in the front ends of these cars, they flex so much. At some stage, I want to remove the underseal, take it all down to bare metal, and start welding the **** out of it. I will of course call an ambulance before going for a test drive.
 

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aznsaab said:
You sound like an engineer Steve, You wouldn't happen to be one? :cheesy:.
... no, I just stayed at a Holdiay Inn Express last night ;) . (this may not translate across the pond, the adverts for the hotel chain implicate that staying there is such a smart idea, it makes you smarter). Actually I've worked as a mechanical engineer in the past, but in reality I'm a tech-geek number cruncher type. I probably SHOULD have been an ME .... but with my 49th year approaching at warp speed, it's not time to change careers.
 
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