411 Windscreen rubber

[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.