Need info: Lexan Rear Window WITHOUT SCREWS
 

Hey pelicans,

I've seen a few pictures from race/street builds of cars (including Jack Olson's BB2) that have a lexan rear window without screws!

Most have used a getty flush mount frame or equivalent, but I haven't been able to find any info on how the window was physically fastened to the frame if external screws weren't used. It seems that urethane alone wouldn't be enough to stop the negative pressure from pulling the window out... But obviously something is working to hold it in there.

If anyone has any info or experience on this, I'd greatly appreciate the feedback.

Cheers,
Justin

They all have screws. BB11 had the screws covered, but with a lexan window you need to have it screwed in or it will pop out.

Yep Rod is correct. Jack "cheated" on his car and covered the fastening with chrome tape to make it look like bright aluminum trim. Read both links below- they're not the same thread

http://forums.pelicanparts.com/porsche-autocross-track-racing/573535-getty-flush-mount-frame-kit.html​

http://forums.pelicanparts.com/porsche-911-technical-forum/266911-getty-design-flush-mount-frame-kit.html​

If you can effectively clamp the lexan to the Getty frame, the urethane will hold the lexan in place. The urethane is basically windshield glue. I have used the 3M Windo Weld product in a caulk gun tube and it works very well. It basically turns to pure rubber when cured and is a VERY good adhesive. I really doubt the lexan would come unglued from the air pressure it sees.

I think the greater challenge would be how do you make the adhesive look clean? A lot of guys paint a black or body color band around the lexan to give it a clean finished look. With the urethane it'd be hard to make the mating area between the lexan and the frame look clean?

what about fitting a front windshield?? Does the gasket suffice?

I tried (and tried) to get a lexan front windshield into my race car - what a PITA! I ended up going back to glass (I still used clips, but again it is a race car).
I wouldn't trust it to stay in with just the seal and trim. The lexan is just too flexible.

In an impact even the well-fitted glass jumps out of the windshield frame. Sure it's heavier so you'd tend to think it would have more inertia to leave the car. But the glass also fits better so it should stay in place better than the lexan. So, windshield retainer clips are recommended regardless of which window material you use. Also do no let the clips lean on the glass if they are not padded. Over time they can cut into the glass and your windshield will crack.

I have Lexan just installed on my RSR used the rubber seal. Seems to be a bit play at the bottom of the windshield. This weekend I intend to install retainer clips from TRE. This is my first experience with lexan 1/4 thick

Thanks for the info guys... Will update with the final solution.

I had lexan all around at one point. Its just not worth the hassle. I ended up putting the factory glass back in. For the windshield I used a new replacement China version which is about half the weight as the German original. Most auto glass companies will carry both versions.

And for that I am thankful. I bought Rod's rear 1/4 frames and rear window frame! SmileWavy

But my application is a racecar so fit & finish of the end result is a whole different ballgame

lol, thats funny. I should clarify that mine is a street car as well so for street application it wasn't worth it. Track car is different. :)

I have had a lexan rear screen in my rally car for years. It was cut to the same dimensions as the glass original and is located by the original seal. No problems in nearly a decade - including many tarmac rallies (with jumps) and countless track days.

I never had screws in mine, Regular gaskt with a brass round rod inserted in the once used chrome strip.
It did not come out at a indicated 150 MPH

Have a lexan rear window in my race car, straps on outside, it sucked in at Fontana, it's now bolted to the straps. My buddy spun at Buttonwillow with a lexan windshield and no clips and blew it out of the car. Scraped to crap, but made it through the weekend. I like my glass windshield