Well, that didn't fit

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peterc
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Re: Well, that didn't fit

Post by peterc »

If I can stick my oar in I would suggest the ‘fussy bit’ is because they are made of angle and have the numerous lightening holes.
Make them out of flat bar like all the samples that Migge put forward and they would look better and could stay in Ali colour or even blue to match the outer sections of the hardtop.
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nikbj68
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Re: Well, that didn't fit

Post by nikbj68 »

I can understand the straps on bubble top screens(and 111JX, which also has just a rubber screen surround) but on LM tops with bolted-in screens, I just don’t get it. Unless it stops ‘drumming’, but I did that by introducing tension to the screen when fitting. (Thermosetting a curve into it would also work...)
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CobStang
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Re: Well, that didn't fit

Post by CobStang »

My understanding is that they are there to stop the screen blowing out of the rubber. If the screen is screwed in (a) you don't need them (b) every time you get out of the car you are going to get asked - why are those strips there ?
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StewbieC
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Re: Well, that didn't fit

Post by StewbieC »

If I can add my tenpenneth, a couple of points
The GRP tops, despite being well made and very strong, are still able to flex considerably along the back edge
Claytonrite seals are very good but only engage around 5-8mm along the screen and hardtop edge, if there is a slight deviation on cutting the screen edge or top edge it may be less
The rear of the screen is a very low pressure area (demonstrated by the soft tops bulging out above 50mph), I could "get some scotch tape and a ball of wool" (in an American accent ala Le Mans 66) to prove it...
My straps are purely precaution rather than cosmetic, I'm not fussed if people don't like them they are more than entitled to their opinion which is fine.... :P
I'd prefer to have lap belts in a car but I've also had a 50mph head on collision and I wouldn't be here today if it wasn't for the 3 point belts. The bruise on my shoulder rather than a smashed in face after the smash proved that.
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nikbj68
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Re: Well, that didn't fit

Post by nikbj68 »

I like the way you’ve done the screen straps on your screen, Stu, in fact the whole top is a masterpiece! 😎
I took Dad for a spin in mine, 2 minutes up the road to get a takeaway, and just did the lap belts up.
He said he’d seen what happened to Nick Granville-Smith, similarly belted, and wouldn’t let me move until I’d put the shoulder straps on. 👍🏻
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KevinW
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Re: Well, that didn't fit

Post by KevinW »

Daft question of the day perhaps: how exactly do these straps stop the perspex/glass blowing out? I can see it would hold a dislocated panel on the car rather than have it crash down the road, but there seems to be a gap between the glass and the straps that would still allow it to wriggle out of the rubber channel? Maybe I cant see the detail properly.
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nikbj68
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Re: Well, that didn't fit

Post by nikbj68 »

No daft at all, Kev!
On the Le Mans tops, most are redundant as the screens are bolted, but 111JX isn’t, and has the biggest gap. I would guess that screen would bulge as far as the straps but not pop out, but would I trust it?! Hmmm... dunno, but it seems to survive!
On the bubble tops, it may help to prevent the aperture itself opening as much as keeping the screen in place.
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KevinW
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Re: Well, that didn't fit

Post by KevinW »

nikbj68 wrote: Mon Jun 29, 2020 11:39 am No daft at all, Kev!
On the Le Mans tops, most are redundant as the screens are bolted, but 111JX isn’t, and has the biggest gap. I would guess that screen would bulge as far as the straps but not pop out, but would I trust it?! Hmmm... dunno, but it seems to survive!
On the bubble tops, it may help to prevent the aperture itself opening as much as keeping the screen in place.
- ah got it- think that last sentence is key - it would only need to move a smidge to 'un-ping' a tiny section of the rubber, already under pressure from the perspex wanting to push out at the back, unfurling an unstoppable cascade of extra cost and :oops: :oops: :cry:
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clive
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Re: Well, that didn't fit

Post by clive »

The aerodynamics of a hardtop, and hood are similar to an aircraft wing in that the air travelling over it causes reduced pressure hence the soft top popping up at speed. The straps could prevent the rear screen being sucked out rather than pushed out from the inside.
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agnoraan
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Re: Well, that didn't fit

Post by agnoraan »

I've decided not to fit any sort of straps the the rear screen.....well, for the time being at least ;-) :lol: :lol:

Nige
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