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MG Midget and Sprite Technical - More Scraping Revelations

This is taking forever - probably because the prospect of toddling out there and getting filthy again isn't alluring.

Can you welding types tell me what's gone on here? These double skin chassis webs are different. Here's the nearside:-

Nick and Cherry Scoop

. . . . and the offside:-

Nick and Cherry Scoop

It looks like whoever was operating the spot-welder got a bit close to the edge on the offside.
Dave O'Neill 2

Oh, OK. So that could be straight from the manufacturer?
Nick and Cherry Scoop

Is that an optical illusion Nick, or is the profiled edge of the triangle raised outwards, rather than inwards, on the outer face of the n/side web? If not an illusion, then it is assembled wrongly, - possibly from factory original which makes your car utterly unique and extremely valuable.
GuyW

That's all I could see Guy. But I wonder if there's been a repair/replacement sometime as the welding technique seems very different to me.

Also it looks like a horrid moisture/gunge trap to me.

Nick, is there something that worries you about this?
Greybeard

Guy

The triangle looks normal to me.
Dave O'Neill 2

Dave, that's why l asked - is it an optical illusion? I can look at that photo and make the edge of the lip appear to protrude outwards just as easily as recess inwards as l focus on parts of the edge. Its an odd effect!
Strangely the other one doesn't do this with the shaped edge clearly bent inwards as it is supposed to.

Nick can confirm the 3 dimensional reality. :-)
GuyW

It looks normal to me too, but the two different kinds of welds makes me wonder if one of the apprentice pieces got into the line at the body place, the offside part looks as if it has been worked on some time back awhiles

There is supposed to be drainage inside the pair of webs too, it only takes two bits of roadside gravel and a pocketful of grit to block them up

Small holes I recall

Worth a look underneath later on

When it's a bit warmer

brrr
Bill sdgpM

Here's a blow-up of the offside.

It looks like the spot-welder was moved while it was welding.

Dave O'Neill 2

Yes, I can see that the spot welds are different. The gun trigger has been held on slightly longer (I doubt they were automated at the time) and the tips moved slightly as the weld was finished. I doubt the difference means its been worked on since factory assembly. It would be difficult to get a resistance welder onto those welds once the sub-assembly component was fitted in the car. If it was a repair I would expect it to be done either with plug welds or in earlier days with gas and the welds would look distinctly different. Its conceivable that a complete sub-assembly has been fitted, but it seems unlikely on your car.

I think it is original factory and is just showing the variation in welding technique between two fabricators. Or maybe they are a before tea break and an after tea break examples.
GuyW

I like the tea-break comment !
once you have seam sealed it, Bonda Primered it and applied your choice of chassis paint, it wont look much different form one side to the other.
P Bentley

Sorry to be late back.

No, not worried, just intrigued, and keen on history. Most of you will know (look away now) that I'm the second owner, the first chap had it from 1960 to 2003, and that he kept exhaustive notes of everything that happened to the car. Or, so I thought.

Now, this is the first time it's had all the muck and underseal taken off, and I've discovered a new sill on the ditchside, and welded repairs in what I guess are the usual places, i.e. where paint and fresh air can't get to both faces of a panel. So the floor at the back end of the sill, the rear wheelarch front face, the rear wheelarch apex where the snake-box runs around on the inside, the front wheel arch face that caps off the sill - all repaired, and none of them are mentioned in his diary.

So that's put paid to years of boasting and smugness: I blush when I think of all the times I've assured Guy that everything's original, when I've measured something. Remember how the two sill point to rear point dims didn't agree? Now we know.

Back to the chassis webs. Sadly the nearside dishing is conventional, Guy. No entry in the next Special Sprites book. I think what really prompted me to ask was the fact that, after an hour or so of scraping in the wheel arch, everything came off the bottom half of that web in one scrape, leaving bright metal as you see. The black muck that dropped onto the floor had no paint in it.

Just wondered.
Nick and Cherry Scoop

BTW, in the recent discussions on treating bare metal (Guy and Bill mainly, with comments from Bob), I don't recall Bonda primer being mentioned. How does it rate?
Nick and Cherry Scoop

Lawrence swears by it, and I've covered the underside of my B with it.

It may be a few years before I can report back on its effectiveness!

Dave O'Neill 2

Lawrence used to swear by it (literally)

I have just degreased stripped (the paint, not me) de-rusted and Bonda-primed the interior of mine. If you don't mind waiting a bit I will tell you how it performs in 20 or 30 year's time.
GuyW

LOL Dave, whilst I typed, and looked for a photo, almost the same words!
GuyW

I used a 2 pack polyurethane primer on the underside as it is waterproof and dries to a harder scratch resistant finish than Bonda primer. But Bondprimer inside.

I also do the first coat of BP before seam sealing as it is very runny and seems to seep well into seams and goes into gaps. I also like alliteration.
GuyW

Phorgot the photo!

GuyW

i was advised that Bonda Primer is the stuff by a guy who is local to me who works on high end coach builds. I have brush applied it to the Mini I am doing and for home use (I don't have a two pack set up)I found it easy peasy to use. Latterly I have also sprayed it over brackets, radiator cowlings etc and found it easy to then overpaint with cellulose. So it gets 10 out of 10 from me.
for some reason the Pics I wanted to share are not loading, but you get the idea from the others already posted.
P Bentley

Nick
Been away so late to the party! Agree with others, spot welder drifting a bit. Maybe Friday afternoon? I doubt it'll come apart though, you'd be surprised how strong even a couple of (proper) tack welds are.

I don't know anything about Bonda - it wouldn't be used on a new shell. Seems appropriate for restored panels though as in Guy's case.

Bill
W Bretherton

This thread was discussed between 26/04/2017 and 29/04/2017

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