R129 - Soft Top replacement, recommendations?

[LeaUK]

No reply from Carhoods for over two working days Guess they are bored of my questions!


stats

Here are my concerns:

1. If the material isn't Wopavin I would like to see the data sheet to compare it's quality, but Carhoods will not provide this info which I find a real shame and little frustrating.

2. MB chose this material thickness carefully and can been seen by their choice of 1.25mm and 1.5mm. Why two sizes? If the Wopavin isn't the same as the OEM thickness (and Gurit warned me of potential life span issues) how long will it last.

Of course Wopavin may have been the most suitable at time of design and so modern materials maybe be far superior, 'Ultralite BUV' as mentioned by JJ maybe one of these.

Both my concerns above focus simply on durability, ie if I spend £1000 will it last more than the 1 year warranty and preferably 5 as I'm planing on keeping the vehicle for around this period.

For Wopavin, let's assume window durability decreases linearly with thickness:

1.0mm /1.5mm = 0.666666

My hood split at 13 years old so, 13 * 0.66666 = 8.7 years..

As a finger in the air presumption this looks promising but I'm assuming linearity and that my car has had 'average' hood usage throughout its life.

????

Maybe I worry too much but I'm a techy and so need to question...

Lea

 

[liammc]

Having had the 'lesser' quality plexiglass sewn into my soft top for a couple of months I have certainly noticed some diffences in quality.

With the heat we're having at the mo the plastic gets a fair bit softer so after having the roof folded the quarter windows come out with quite a few creases. These seem to disappear over the rest of the day but the original ones were a lot less prone to this.

The brand stamped in the glass is ULTRALITE BUV

HTH

 

[LeaUK]

Hi liammc

I haven't considered physical differencies! Any chance of taking a piccy so we can really get a feel?


I'm off to review the spec for the ULTRALITE BUV http://www.polyone.com/bizunit/films/films_reg_spec.asp and compare with Wopvin http://www3.gurit.com/auto/products_wopavin.php.


Lea

Edit

So the specs are a little tricky to compare as Ultralite is US based (I wonder if this is the material Carhoods use) and refer to many ASTM tests whereas Wopavin (being German) refer to DIN standards.

 

[LeaUK]

Have emailed Aresma in Germany as recommended by Gurit as one of the only takers of OEM thickness Wopavin.

 

[liammc]

LeaUK, will do although it's not that hot here today so the creases may not be as bad.

My only concern is when having the hard top on over winter I'm not sure how it will look after months of being folded.

 

[l5foye]

Lea - your research efforts are much appreciated and I will wait the results before doing anything. I have just noticed that Prestigetrim charge the same labour cost for replacing the rear windows as they do for replacing the whole hood. As there is only about £200 cost difference in materials between the rear windows and a complete hood, it would seem to make sense to replace the whole hood rather than just the windows. We need a plastics expert to tell us the best material and the optimum thickness. I wonder if MB chose a thinner material for the side windows because they are subject to more bending?

 

[liammc]

Well these pics should give you some idea.....

Its easy to grab as below. I would struggle to do this with the original, but bear in mind the old windows were quite stiff to the point of becoming brittle....

about 10 seconds after grabbing it......

It is definitely more 'pliable' than original and recovers quite well, and is by no means poor quality.

Hope this helps

Liam

 

[l5foye]

Lea- you said you are a techy,so here goes-
Gurit-Worbla in conjunction with Bayer, have brought out a new rear window material for the BMW Z8- called Flexglas 9120 which is supposed to not yellow after long term exposure to UV light and is able to withstand the brushes used in car washes. It is claimed to be the best in thermplastic polyurethane. I have not yet been able to find out how thick it is.

 

[LeaUK]

Hi Guys

Sorry for the delay in posting but have been on a weeks break on a farm in Somerset - a beautiful county and couldn't have wished for better weather..

Unfortunately I have had no response from Aresma or Gurit (but my Gurit contact is away until next week). I'll try Aresma again.

I have reviewed both data sheets but as I'm not a materials specialist it's tuff going, that's why having liammc's comments is so useful. Sometimes nothing beats the real thing. Also, as you say, just because Ultralite appears more subtle under the heat this doesn't necessarily translate to poor quality. Maybe we need a contact someone who has had Ultralite fitted for over 5 years! My quest continues until either my windows completely crack and I'm desperate for a replacement, or that I finally make some real progress.

I have had one thought whilst being away, I have a 'friend of a friend' who works for MB so maybe he will be kind enough to reveal who MB use to fit their replacement tops, he may even know who make the tops (bet it's not Benz!). It may boil down to buying a MB top (£1500) and ask a local supplier (maybe cardhood warehouse) to fit.

I'll update as and when.

BTW - Flexglass 9120 looks interesting, off to read a little more.

From my initial research it seems as though only two or three manufacturer's of flexglass are used by hood manufacturers: Gurit 'Wopavin Flexglass 9101' (Swiss); Polyone's 'ULTRALITE' (US) and Gurit-Worbla's 'Flexglas 9120' that appears a recent addition so the downside I guess is there's no real evidence on durability.


Cheers all
Lea

 

[IanA2]

http://cgi.ebay.co.uk/MERCEDES-SL-R...ryZ10398QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Is this any use to anyone?

 

[LeaUK]

Thanks Ian

EUROTOP GmbH & Co. KG, Mühlstr. 16, D-72622 Nürtingen, Deutschland / Germany - a manufacturer using the correct size flex-glass and at a good price

I'll try and make contact to find out more - unless someone else wants too?

Here's the most important part of the eBay ad:

To be known: Flexible Polyglas rear window with an original thick-ness of 1,25 and 1,5 mm, automotive improved, sewn-in steadily


Material: Cloth Sonnenland sun resistant, original for Mercedes, Porsche, Audi or BMW - protected against sun fading

 

[LeaUK]

An update - a long time coming I know but had to move the home office and PCs, decorate, build a shed and base, some DIY etc,etc. violins anyone?..


Today I received a quote from Gurit for sheets of respective 1.5mm and 1.25mm Wopavin, however as one would expect the minimal quantities (although not completely prohibitive) would make purchasing uneconomical - unless there are 20 or so other's who want new quality OEM windows - and around an extra 30 who just want side windows!

Or of course perhaps the excess could be sold to the UK hood manufacturers? - but I doubt it!

There is also good news; although I never previously received a quote from Aresma, Gurit mentioned that I should receive one shortly - many thanks to Gurit for this assistance.

I suspect now is also a good time to delve into EUROTOP GmbH & Co and so I'll also approach these guys too.

I'll keep you updated.

Lea


Edit

Prices from Eurotop - http://www.eurotop.de/site_eng/preisliste.htm#

DB 300SL-600SL Typ R129 ab 90 - - - 699,- € 699,- € 749,- €​

The 749 version is classed as:

Sonnenland exclusive Sonderfarben

as opposed to:​

Sonnenland orig. BMW Mercedes Porsche​

any thoughts?​

​

 

[stats007]

To be honest Lea I think you're being way too fussy. Having seen Carhoods work on 107s I wouldn't hesitate using them if mine needed replacing. R129 OEM windows I've seen rotten in 4 / 5 years with misuse - it's all down to how you look after them.

 

[LeaUK]

Hi Stats

I'm just trying to make an informed purchase to be honest.

I'm not convinced by Ultralite for several reasons:

1. Wopavin is proven to last 15 years

2. I have no evidence that Ultralite will last longer than 1 year - I'm not saying it wont last 15 but just cant find the evidence

3. I'm personally not convinced by the high malleability of the Ultralite (see liammc's pics) and the time it takes to reform.

As I have several choices in hood Mmanufacturer I'm keen to ensure these are educated, hence my enthusiasm for delving a bit deeper than the average MB owner.

BTW - did you ever replace your windows in the end?

Lea

 

[stats007]

If you're worried about splitting I would suggest a thinner more pliable plastic would be better. It's obvious when the roof closes there can be a lot of rubbing and bending because the OEM material is quite thick. I would suggest it is like this to reduce sound levels in the car.

I have never had any problems with my windows in the three SLs that I've owned. I've used Hindsight on all of them though Mother's Plastic Polish has been recommended and is far cheaper. I only recommended Carhoods because of the work they've done through MBOC. I would also think about the quality of workmanship when having a new hood made and / or windows fitted. I've seen windows fall out because the stitching has been poor.

 

[LeaUK]

stats

Don't get me wrong I am listening and understand your viewpoint - in fact it's very useful many thanks. Also my comments aren't based around just Carhoods but on the material commonly used in the UK. And as we now know that's Ultralite or the incorrect thickness flex-glass Wopavin.

Anyway, I have had great news from Aresma today. They quote 615 euros + shipping 27-37 to UK. They confirm their hoods are the correct Wopavin thickness and sonnerland canvas. Aresma are also a hood manufacturer which is a good news.

Here's another interesting thing. Aresma are willing to supply Wopavin sheets of 1.25mm and 1.5mm at 30 and 40 euros respectively Now that's excellent news. We can now purchase real OEM rear windows ourselves

So my next round of questions will be:

1. Can Aresma supply the flex-glass sheets already cut to size - ready for stitching?

2. Will Carhoods be prepared to fit a complete hood made by Aresma?

3. Will Carhoods be prepared to fit new rear windows supplied by me? - should I just go for rear windows and not the full top

4. What's Carhoods preferred window format - full sheets or cut to size?

We're nearly there

Lea

 

[l5foye]

Well done Lea.
You ask, among other things, about getting Carhoods to fit the rear windows. As I recall, the cost of fitting these is the same as fitting the whole hood. It might be false economy to just replace the windows.

 

[LeaUK]

Hi

The cost of replacement rear windows from carhoods was around £400 - a whole soft-top was £1000 so it's still a good option.

 

[stats007]

Is this of use?

 

[LeaUK]

Blimey, that's cheap. But as it's only the rear section I guess I would suffer colour mismatch

Big thanks for the link though, just goes to show anything and everything is available on ebay eh!

Lea