Changing to Polycarbonate?

[alias23]

We all know the rear rail gate window weighs a substantial amount... Anyone else thought about how easy it would be to swap the glass to polycarbonate?

[alias23]

Can anyone confirm the actual (even if rough) weight of the rear glass in the tail gate?

Looks as though i've found a source who could provide a replacement in polycarbonate, very reputable company, what we're trying to ascertain is what would be the main weight saving benefit. For example if its only 3Kg changing from glass to poly then they themselves would not advise, but if its 10Kg saving then that slightly makes the prospect quite attractive and one which could help justify them making the part.

Any thoughts, feedback, suggestions much appreciated. Thanks

[Crouchy]

no idea im afraid but this could be interesting

You could even have a clear louvered panel much like a Ferrari F40, hopefully with a bit of extra clearance so we can run a charge cooled TVS1900 as soon as SSC release the kit.

Edited June 1, 2016 by Crouchy
spelling

[French Frie]

the weight saving with the Sport 350 louvered pastic thing is supposed to be 3 kg (http://www.thelotusforums.com/latest-news/lotus-cars-news/driven-exige-sport-350/), so I assume a polycarb rear panel may save one more kg maximum, both parts being plastic sourced ...

 

[mbes2]

Would it even really be worth it, Ive got the glass fitted and its lush being able to see out the back, compared to the S2 exige.

Plus,saving just 3kg, Im better off myself going on a diet for a month to lose more kg

[CocoPops]

3kg quite high up in terms of CoG would make more difference than you having a few large shits to lose weight Mark

 

[Crouchy]

I dont think I could justify the outlay to save 3KG.

[mbes2]

2 hours ago, Crouchy said:

I dont think I could justify the outlay to save 3KG.

Snap.

Unless your able to drop 50-100kg with lightweight parts and in a race series, I don't see the point for a road / odd track day toy.

Stripping my old VX220 was my next step but never had the heart to do it fully.. so upgraded to the v6 lol 

Lee.... before each track day, its like king kongs 1st dump of the day with me... 

 

[Arun_D]

Do we even know what the outlay is yet that we're trying to justify or not?

[alias23]

Cost for a poly rear windscreen likely to be £350-550 based on current design thinking. As in straight swap in poly no louvers at this point.

However fair to say for a 3kg saving we don't feel it would be justified. Even though the press suggest the 350 shed 3kg by using louved plastic many peeps still feel the glass is a lot heavier than quoted and I feel like I agree.

Just need confirmation may try and figure out a way to ask a windscreen repair company to check weight based on a replacement request...

As per my previous post 10kg saving or in that region then it would be bloody worth it!

[Arun_D]

I don't have my Exige to hand, but who fancies measuring up their rear screen dimensions for a rough mass check (using Saint-Gobain Sekurit's density value for tempered auto glass of 2500kg /cubic meter)? Assuming 3mm thickness unless we know better?

What's that, Imran, you volunteer?! Very kind of you 

[alias23]

1 hour ago, Arun_D said:

I don't have my Exige to hand, but who fancies measuring up their rear screen dimensions for a rough mass check (using Saint-Gobain Sekurit's density value for tempered auto glass of 2500kg /cubic meter)? Assuming 3mm thickness unless we know better?

What's that, Imran, you volunteer?! Very kind of you 

I'm in London away from home but back tomorrow and would happily measure up sounds like a good idea Arun!

[RedViper]

I could be interested but actually want the louvres as additional cooling is always going to be of benefit.

Is nobody able to make a straight copy of the S350 panel. Il admit I wouldn't know where to start with it.

I bet the wing is a significant contributor to weight on the boot lid too. If I had to guess I would imagine the whole boot lid complete with wing would be 10-12kg.

[CocoPops]

I guess HK Fever or CK Lim will be producing Carbon Fibre copies at some point.

[French Frie]

16 hours ago, alias23 said:

As per my previous post 10kg saving or in that region then it would be bloody worth it!

so, I'd rather go the lithium ion battery route, if not already fitted  ! about £500 with trickle charger  : http://www.braillebattery.co.uk/index.php/braille/product_batteries/gu1r_combo

I'll then even consider to relocate it in the engine bay, to save some space in the boot...

[alias23]

6 hours ago, RedViper said:

I could be interested but actually want the louvres as additional cooling is always going to be of benefit.

Is nobody able to make a straight copy of the S350 panel. Il admit I wouldn't know where to start with it.

I bet the wing is a significant contributor to weight on the boot lid too. If I had to guess I would imagine the whole boot lid complete with wing would be 10-12kg.

If someone could get me the louvred panel I can make a mould

5 hours ago, French Frie said:

so, I'd rather go the lithium ion battery route, if not already fitted  ! about £500 with trickle charger  : http://www.braillebattery.co.uk/index.php/braille/product_batteries/gu1r_combo

I'll then even consider to relocate it in the engine bay, to save some space in the boot...

That Braille is actually on my list of next additions to the car along with some extra aero

[Hangar 111]

Rear window is approx 750mm x 650mm, and quite thin, I'd guess about 3mm.

Dave

 

[RedViper]

27 minutes ago, Hangar 111 said:

Rear window is approx 750mm x 650mm, and quite thin, I'd guess about 3mm.

Dave

 

That puts it about 3.65 kg. sounds about right with weight saving of 3kg and louvred panel weighing half a kilo 

Edited June 2, 2016 by RedViper

[Arun_D]

^My calculator agrees. 

[RedViper]

1 hour ago, Arun_D said:

^My calculator agrees. 

?

[alias23]

In that case for me the pros vs effort and cost don't add up

[RedViper]

If someone made a replica louvred panel for £300-£400 I think it would be worth it. any more and I would agree with Imran. I also enjoy the actual process of doing a car job as much as the finished results too.. maybe I should learn to play golf

[mbes2]

How about this nice carbon version 

[RedViper]

How many kidneys does one need to sell to purchase one of those?

[alias23]

Circa a £1k for the ElTech one in the pic above.

From memory it weighs 5kg