411 Windscreen rubber

[Kevin H]

Do other 411 owner's rear windscreen seal/rubber have a join at the bottom centre of the screen? (it's probably very similar to the other V8 cars)

Are windscreen rubbers still available?

Last but not least, can anyone describe the process for removal and refitting of the screens?

[Rubbond]

Kevin,
Removable fixed window gaskets are extruded rubber compounds which are
either vulcanised in line (hot air tunnel with or without UHF heaters),
cut to length and then corner-moulded (injection moulded in a mould), or
pulled around a metal former (uncured) and cured in an autoclave. Bottom
centre these are butt-jointed. On the finished gasket, on one side two lips
fit snuggly over the bodywork and on the other snuggly over the glass. On a
modern car the windscreen is glued in to stiffen the body.
I have never done the job myself, but refitting is done by first fitting the
seal around the glass, and then the gasket fitted over part of the bodywork
and the rest by pulling a piece of cord around the window between the gasket
and the bodywork. This has to be done from inside and outside the vehicle,
so you need a second. person. Preferably from your local Carglass shop!
Removing will be the reverse, but I dont know how you would get the string
through safely without risking damage to the glass. Maybe they use a curved
sailmakers needle or maybe just a screwdriver.
I can imagine Bristol windscreens were taken from another vehicle? That
might help finding a new windscreen gasket.
Try to make sure they are made from EPDM rubber. These will last about 5
times as long as ones made from SBR. SBR smells like rubber, EPDM hardly at
all. The same applies to radiator hoses - aftermarket hoses are often still
made from SBR. If you can find a hose from a modern vehicle with the right
ID and roughly the right shape, it will last much longer than a cheap after
market copy of the original. VW has the toughest specifications on coolant
hoses in the auto industry.
With best regards,
Andrew Knox.

[Kevin H]

Thanks Andrew.
I knew there was a piece of cord/string involved somehow. However, it's probably not wise to "learn the ropes" on a windscreen which could be very hard to replace.

We've had some discussions about V8 Bristol windscreens before on the BEEF mail list, and probably before that on the the BOC forum, and unfortunately I can't recall anyone ever identifying the front or rear screens as coming from another vehicle.

The but joint at the bottom on my rear windscreen isn't very well butted together and I'm concerned it will let water in (not sure where it would go). I think this may receive a dollop of windscreen sealant for the time being!

Also, with the front screen, the metal surround which fits into the outside of the rubber moulding is springing out at the top joint - the centre joint piece was held in place with silicone rubber. Apparently there is a brass frame under there which goes all the way around the screen and it has been suggested that this has been bent when the screen was removed at some stage and it may be able to bent back into shape without removing the screen.

Can anyone shed any light on this. A cross sectional diagram would be really nice

[Rubbond]

Dear Kevin,
Not sure about the brass insert (I doubt it very much) but would be happy to
check this with a manufacturer. The first one that comes to mind is Schlegel
(which I think became Metzeler) in Coalville (Derbyshire?), who supplied
most UK manufacturers, including Land Rover.
Standard Products in Plympton may also still be making these parts, but I
think they are now called Cooper Standard.
Need to be quick before they all go bankrupt, as they are 100% automotive
parts suppliers. Sad times.
Will revert asap.
Andrew.

[Sam410]

Originally Posted by Kevin Howard

Are windscreen rubbers still available?

Bristol Cars in Chiswick had 410 screen rubbers earlier this year, and given the company's current work on 411 's6' cars I'd be surprised if there were no 411 rubbers.

[seanmcs]

From Sean mvSharry

If you have a good specialist windscreen guy in Melbourne, ask him
first. I found that the Company's 406 replacement screen rubbers
were as old as the car and they wanted GBP 220 for the front alone -
15 years ago. Ralph Moore Autoglass at Botany NSW found the
identical profile, which came from a common UK van, for nearly
nothing. Brand new Asian stock and still going strong on the car in
Victoria.

Sean

[Hugh]

On the subject of windscreens, does anyone know if Bristol Cars used a
windscreen for the 603 and onward from a donor car of the 70,s.
I will eventually need to replace the Britannia's screen.

Hugh

[seanmcs]

Sean McSharry

Hugh:

Would ask Ralph Moore, Mascot. He might have an idea.

Best. Sean

[Rubbond]

Silly question maybe, but doesn't the factory know what windscreens were
used, or have parts available?
Rgds,
Andrew.

[Kevin H]

I would put money on it that the windscreens at least up to and including the 411 are unique to Bristol. But even if you were to call the factory (or Bristol Cars Services), they're not very likely to say "oh yes that's out of an Austin Cambridge", because understandably they want to make money out of selling spares, like every other car company. Not much point in stocking them otherwise.

I'm sure BCS can supply them, after all, it's quite a critical item, but I shudder to think what it would cost to safely ship one to Australia. I have a dim recollection of a price of 900 GB Pounds for a front 411 screen, that's just the UK purchase price, although I may be confusing it with the cost of a secondhand front bumper.

Fortunately I don't need one at the moment (hope I'm not tempting fate!)

[jimfoz]

Does anyone remember this edition of salvage squad when they restored a 407? This was 5 or more years ago and they accidentally cracked the windscreen of the car when restoring it and had to pay 400 odd pounds for a used replacement from the factory which suggested they were unique. It may not be helpful for a 411 but it might still be informative anyway - surprised the link to the whole programme works still!

click on the web link http://www.arnolt.com/main-frameset.html
Then go to resources, then click on videos.

[Dale409]

I just know this is going to be of absolutely no help in sourcing a windscreen but I did hear some years ago that the windscreen for the 406 presumably through to the 411 was originally the same screen used in the post war Delage D6. Now all you need to do is pop down to your nearest Delage stockist and see what they have in stock.

I guess if you follow the trail, Delage to Delahaye to Hotchkiss to Citroen, so the local Cit dealer it is. ;-)

Dale Allen

[Nick Challacombe]

When this subject came up re the 407 on salvage squad, it made me think as
they paid Brian May £350 alledgedly for one.

I phoned up Autoglass and they sent me one by return for £70.00 plus VAT.

I bought a rear screen on ebay last week for £24.00

Food for thought,

Nick

[Hydroglen]

On the subject of windscreen rubber, it should be remembered that it has a
shelf life. Therefore buyng old stock from the Company is questionable and
I am surprised they would even sell it. The big issue is the fitting /
installation. Old stock is harder and will not flex and bend when
installing and it becomes quite a task. You might as well forget about a
good water seal. Unfortunately I speak from experience on a 66 BMW, and I
see no reason to think that the rubber used on Bristols would be that much
different. Age is age.
Dorien

[Nick Challacombe]

The windscreen rubber I bought from Bristol for my 407 was not old stock ,
Brian Marelli
assured me that they had recently had a batch made up and I bought the last
of it. Put it into my Bristol
in 2000 and it has done the job.

[Rubbond]

Actually there are several ageing processes involved, including physical
ageing, which applies to all materials - this is where molecules descend to
their lowest energy levels which is why you can't easily cut old glass.
With rubber the key issues are
1) heat ageing, which is basicly oxidation,
2) leaching or addition of plastisisers (softening oils) which won't
normally happen on the shelf, but will if you get engine oil on your
radiator hose, and
3) the effects of Ozone and UV light. As most rubber profiles are black, the
carbon black will absorb the UV energy and if stored indoors, the UV won't
have much effect.
With SBR profiles, used in the 1960's, the biggest culprit is heat ageing
and/or Ozone cracking. The double carbon=carbon bonds in the polymer chain
break open and the polymers strength has gone, like an old elastic band.
Polymers with a saturated backbone (i.e. c-c bonds instead of c=c) are far
less susceptible to heat ageing and UV exposure. These polymers are denoted
with an "M" as suffix, i.e. CM, EPDM, FKM, etc..
SBR, NR and BR, all used in tyres, are very susceptible to both heat ageing
and UV light, though being black, this helps the latter, but worsens the
former in the sense that they get hot exposed to sunshine. Ozone is what
causes the cracking. Unsaturated rubber molecules under tensile stresses of
about 10 - 15% (i.e.a tyre left flat for several months or the stretched
corners around your windscreen) are highly susceptible to Ozone cracking.
Saturated rubbers are not, hence the need for (in this case) EPDM based
compounds, which were first produced in about 1968. I have cracking however
on the rear (fixed) side windows of a 1998 Land Rover Discovery, where the
profiles were probably a bad fit when made, and are probably still SBR.
So there you go.
Probably best to buy a German car. Their specs are the best in the world for
all rubber parts, including washing machines.
Andrew.

[seanmcs]

Sean McSharry

I can say that the 406 screen is unique and will not got into the 407
nor later models.

Sean

[Nick Challacombe]

I agree, that is why it has a 406 part number and the 407 has a 407 part
number.
The rear screen of my 407 has a 406 part number and was used for many models
up to and even maybe the 411.
Thats why I was so happy to buy one for £24.00.

regards,

Nick