What do you use to seal rear 1/4 glass into frames?

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AndyPen
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What do you use to seal rear 1/4 glass into frames?

Post by AndyPen »

Hi folks,

I had the original Rover stuff but when I try to fit the glass back into the frame it feels very tight indeed. I took one apart after an hour or so of struggling to put it all together and the tape had been cut by the edge of the glass frame anyway. I also tried some from Somerford but seems to be the same thickness and I had a similar problem. It is all just too tight and I feel like I am forcing it all too much.

I know some of you use bike inner tubing, but any specs or recommendations please?
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Peter Laidler
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Re: What do you use to seal rear 1/4 glass into frames?

Post by Peter Laidler »

I thought that the usual stiff was too tight too. That's a good idea to use a bike inner tube - with plenty of KY-Gel to make it........ Anyway.

What about 1mm thick neoprene sheet?

In the end I just got the frame warm-to-hot and then wrapped some plain mastic (not silicon mastic) round the edges of the glass. It jusr sealed itself into the warm frame. And it's still there!
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Re: What do you use to seal rear 1/4 glass into frames?

Post by 360gts »

AndyPen wrote: Sun Jun 23, 2024 9:39 pm Hi folks,

I had the original Rover stuff but when I try to fit the glass back into the frame it feels very tight indeed. I took one apart after an hour or so of struggling to put it all together and the tape had been cut by the edge of the glass frame anyway. I also tried some from Somerford but seems to be the same thickness and I had a similar problem. It is all just too tight and I feel like I am forcing it all too much.

I know some of you use bike inner tubing, but any specs or recommendations please?
Andy,
I use these inner tubes....700 X 20-200 ....one per frame.
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Re: What do you use to seal rear 1/4 glass into frames?

Post by AndyPen »

Halfords for bike tubes will be my next trip then, thanks for the messages and help ;-)
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diz
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Re: What do you use to seal rear 1/4 glass into frames?

Post by diz »

I also used a bicycle inner tube but found it to be too thin; so as an added precaution I smeared black Tiger Seal around the edge of the glass. When fitting into the frame the excess Tiger Seal squeezed out to leave no gap. It was a messy job but easily cleaned up when dry.
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Dr.Mabo
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Re: What do you use to seal rear 1/4 glass into frames?

Post by Dr.Mabo »

The rubber of a bicycle inner tube cannot withstand environmental conditions for long periods of time. At least that has been my experience when I have used the material for underlay seals. It has always shrunk and become brittle very quickly.

That's why I always tend to use normal rubber profile by the meter. You have to free yourself from the idea that the glass, the rubber seal and the frame will fit together properly during installation, even if it should fit in purely mathematical terms. What worked very well for me was a little soap and pulling on the seal. If you pull the rubber in the direction of the frame, it becomes thinner. With the help of the lubricant, it slips into the frame. If you let it relax again, it slips back until it fits. What is left of the frame at the joint is simply cut off. The same applies to the protrusion on the glass. As described here in my Broadspeed thread.

http://mk1-forum.net/viewtopic.php?f=6& ... &start=550
so long
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My previous project:
http://mk1-forum.net/viewtopic.php?f=6&t=28477
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Re: What do you use to seal rear 1/4 glass into frames?

Post by CooperTune »

I have a couple sets to do. I have always used neoprene 1/16 strips long enough to go all the way around. Yes, it is a tad thick but I find stretching it slightly allows the glass to settle into place. Closing the ends can be a bit tricky. Also the strips are wide enough to hang out both in and out. I use a length of SS shim stock forced between glass and seal and with a sharp razor knife work my way around. I'm not a fan of the MK2 1/4s that join top and bottom. Steve (CTR)
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Re: What do you use to seal rear 1/4 glass into frames?

Post by TECH396 »

As an option to the inner tube method, there are two thicknesses of glass 4mm or 5mm and require different thicknesses of material. I used butyl/setting tape just as the factory did. There is 1.2 mm or 1.6 mm butyl/setting tape available in rolls from 25'-50' in length and approx 1.5" in width. I got mine from my local auto glass shop.
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Re: What do you use to seal rear 1/4 glass into frames?

Post by AndyPen »

I tried the usual suppliers (Butyl I think) but perhaps should have tried stretching it?

I have now managed to fit my 5mm perspex windows in thankfully. These are in my old rally car and I can put up pics if people are interested? I have used the Halfords inner tubes and they are ribbed slightly, which seems to fit spot on. Next job will be the glass ones on another car.

Bob1071 helped me with getting the frames sorted and I certainly owe him a big thank you!!
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Re: What do you use to seal rear 1/4 glass into frames?

Post by floormanager »

CooperTune wrote: Mon Jun 24, 2024 3:47 pm I'm not a fan of the MK2 1/4s that join top and bottom. Steve (CTR)
Me neither. Both my rears had rusted through, causing the frame to drop. Thankfully I got a few spare frames from Rolandio and used the good tops out of those to repair my bottoms. Inner tubes worked well for me, with a bit of sealant to take up the slack. At least no dropped frames damaging the paintwork.
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