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MG Midget and Sprite Technical - Frogeye windscreen fit

I am not sure, but I may have a significant structural problem regarding the fit of my windscreen to the shape of the scuttle. 8-(

This body tub has had major reconstruction. One part that I bought ready made was the scuttle top and firwall assembly and I fitted this together with 2 new A posts, using the bonnet curve and the door tops to align it all. As far as this alignment goes it all looks good.

However, now when I retrieve the windscreen from the garden shed and offer it up to the scuttle it isn't looking good! With the stanchions bolted in place and the screen fitted with the 6 small screws the gap between the screen frame and the scuttle isn't consistant. In the middle the gap is around 5/8" whist at either end of the screen it is sitting almost down onto the scuttle. In effect the curve of the glass frame doesn't match the curve of the scuttle. As the scuttle was a pre-assembled unit its curvature across the top was fixed by the shape of the vertical firewall and the drainage gutter. And anyway that matches the bonnet so I cannot see why the gap is so different.

I haven't yet fitted the stanchion plinth rubbers or the frame rubber so perhaps this accentuates the problem, it certainly makes it more visible!

Any thoughts?
GuyW

Guy,

Mine is the same and its the original scuttle! When I first renewed the rubber seal at the base of the screen you could just see daylight in the middle!! The seal settled down and its ok now. I assume your scuttle has the raised 'bump' along the top and the screen goes just in front. to this. This stops the rain coming in the cabin. The rubber pads which have the effect of slightly lifting the screen at the corners.
Bob Beaumont

I had this on my MkII, but not so severely. I cursed myself for having put the dash in first, and perhaps pulled the scuttle down with the centre fixing. But the line of the windscreen is less than 4" back from the bulkhead, so any significant distortion was impossible.

I couldn't think of a counter-measure, so I put up with a seal that curled down onto the scuttle. It kept the weather out, but I'm not sure yours will at 5/8".

On Cherry there is a second strip of rubber under the seal, and I believe it may not go right across - maybe just the centre two-thirds (it's in the garage roof somewhere). PLUS, there was a curl in the middle third of the forward part of the seal, down onto the extra strip.
Nick and Cherry Scoop

Thanks both.

The screen also needs new glass rubber. Looking at the old, perished and now fairly loose one I think there is some scope for reshaping the bottom rail of the screen to match the scuttle curve a bit better, whilst still having enough depth of the glazing seal to meet the glass. I hope so anyway!

At least the body isn't yet painted - not the outside anyway, so there is some potential opportunity to reshape the scuttle a bit. But I am going to order the various rubbery bits and wait before I take any drastic steps with the scuttle itself.

The other variable seems to be the stanchions and the rake of the screen. Those that came with the body had both broken off across the base by the front fixing hole. Quite common I think? I bought a replacement pair of originals (not aftermarket). Looking closely, there is a slight convex curve to the underside along the length going front to back. Maybe thay are made that way as all 4 are like that but it is also the sort of distortion that might occur from people repeatedly pulling on the top of the screen when getting in and out.

Good supplier for this sort of window rubber seals? One hears such tales . . . . .
GuyW

Nick,
I was recently watching a U-tube video which was basically a sales pitch by an American company demonstrating a rather nicely prepared red Buyeye that they had worked on. Part way through he pointed to the windshield screen rubber and said the seal was "correctly fitted with the front edge curled under" He said that most people get this detail wrong and make the leading edge lie flat, but that his method was the correct version.

Of course one shouldn't believe everything one reads, or sees, online. But I wonder?

Yes Bob, my scuttle does have the raised ridge.
GuyW

I had to put a helicoil in the front fixing hole for the stanchions after buying a new convertible hood. So Yesterday I replaced the windscreen on my original scuttle with ridge. Yes the shape of the scuttle and the windscreen do not match. For 20 years I kept the rain outside with some silicone rubber between window seal rubber and scuttle. The rain came in where the wipers are.

Flip
Flip Brühl

Here's my thread of 12 years ago, Guy. You were very helpful.

https://tinyurl.com/yba42r94

I've noticed you use tinyurl, so I have attempted it too.
Nick and Cherry Scoop

I see that our dry humour hasn't changed greatly in 12 years. Yours and Jeremy's that is.
I think my comment related to a wind-up (window) style. There seems to be less scope for fore-and-aft adjustment on a Frog screen.

Have you changed your e-mail Nick? I sent one to an old thorny hill named one and it bounced back. It wouldn't surprise me if you were trying some sort of defence against yellow courgettes.
GuyW

Interestingly though, theory says that the more packers you have (albeit stouter than plinth rubbers), the further apart the stanchions are, and the bottom rail should stretch and lower. For a 5/8" gap at the centre, I calculate that each stanchion has to move out 3/32".

It won't work, of course.
Nick and Cherry Scoop

. . . . or maybe only half that, if the ends are fairly tight to the scuttle for 8 inches or so. Say 1mm.
Nick and Cherry Scoop

But the angle of the base plate of the stanchion is such that packers would move them out, and upwards. But I see the principle. Tomorrow I will experiment with some large penny washers under the stanchion bolts to see what effect this has on the frame lower rail. At least as its not painted there is no nice shiny surface to scratch!

If one thinks of the scuttle as an architectural 3 point arch with the two outer arcs having short radii and the middle arc being much flatter with a longer radius, then the problem on mine seems to be that the outer ends have too long a radius and contact the more steeply curving scuttle too soon.

Thanks for the updated email address Nick. I didn't actually get to read your message as somewhat alarmingly, my anti-virus software (AVG) blocked and quarantined it, alerting me to a contained virus. Trying to infect my courgettes now? Seriously, you may want to run a system check on yours.
GuyW

Just to add to this I've measured the gap between centre of windscreen frame and scuttle and mine is about 3/8" so even on a new shell there's a gap (with stanchions sitting on scuttle). I presume mine will fill with the rubber.
Bill Bretherton

Today I refitted the screen, this time using the rubber plinths at either side and the correct screen stanchion screws. This seems to have somehow brought the centre of the screen down a bit. Whereas the gap at the centre measured before at 5/8" it has now reduced to 3 /8" to 7 /16" max.

This is without the screen base rubber so l now have some hope that it will seal well enough when that is fitted. We shall see!
GuyW

This thread was discussed between 20/04/2018 and 24/04/2018

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