Author Topic: installing windshields  (Read 25667 times)

Flowjoe

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installing windshields
« on: March 29, 2007, 08:05:24 PM »
How do you guys install windshields (and back glasses for that matter) so that they achieve a stock height and appearance?  I know that urethane is the best for sealing but I hear that it is difficult to get the height correct.  Butyl is  a pain but comes in a 3/8" bead plus no one seems to make/cary a pinch weld primer thta is compatible with butyl.

What did the factory use?

JohnZ

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Re: installing windshields
« Reply #1 on: March 30, 2007, 03:29:18 PM »
The factory used a "dam" and Thiokol pumpable adhesive with different silane primers on the glass and on the body opening flanges, which changed to urethane pumpable adhesive in the 70's. GM never used butyl in production, as it won't pass the MVSS 208 Frontal Impact Windshield Retention requirement, and the Thiokol or Urethane adhesive design makes the windshield and backlite structural parts, improving body torsional stiffness. Some glass shops use butyl for replacement glass because it's quick and cheap, but it's technically illegal. The factory rubber spacer blocks established the windshield height for correct flush fit of the reveal moldings to the glass surface.
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jeff68

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Re: installing windshields
« Reply #2 on: March 30, 2007, 04:09:59 PM »
How/where do we go about finding the proper rubber spacer blocks?  My replacement windshield was installed with butyl and all the moldings seemed to fit very well, so I guess it was at the correct height.  Now, the windshield has been removed for body work.  I would like to have it re-installed correctly, so I am curious where to get the proper parts.
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Flowjoe

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Re: installing windshields
« Reply #3 on: March 30, 2007, 04:13:39 PM »
Thanks a bunch John...as always, you are the man.

I have a some follow up questions:

1) what is the best way to replace glass on a current restoration?  By that I mean materials (I assume urethane) and can I do it by myself.  I don't trust a lot of these replacement glass guys so I'm trying to get an idea of what to look for when searching a company out.

2) Is there a source for the rubber blocks that establish height?  I've never noticed any when removing windshields so don't know what or where I am looking for them

Super interesting stuff on structural integrity...I never knew that...nor the front impact info.  Makes me think twice about the cars that I have with butyl in them now (installed years ago by myself).

Thanks again and thanks in advance
Joe

bbd564

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Re: installing windshields
« Reply #4 on: March 31, 2007, 02:52:19 PM »
Since we are talking about windshields, isn't there supposed to be a "ribbon" cloth tape that goes between the glass and the adhesive strip.  I have seen this on original cars, but never have I seen this on cars where the glass has been replaced or reinstalled.

JohnZ

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Re: installing windshields
« Reply #5 on: March 31, 2007, 04:09:56 PM »
Since we are talking about windshields, isn't there supposed to be a "ribbon" cloth tape that goes between the glass and the adhesive strip.  I have seen this on original cars, but never have I seen this on cars where the glass has been replaced or reinstalled.

That's the "dam" I mentioned above; it's cloth-reinforced, and was glued to the glass just inboard of the adhesive before the adhesive was applied; it's intended to prevent any adhesive "squeeze-out" from being visible past the edges of the garnish moldings from inside the car.

Any auto glass shop will have the spacer blocks that set the height of the windshield and backlite glass.
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jeff68

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Re: installing windshields
« Reply #6 on: April 01, 2007, 12:38:06 AM »
So, if the glass is being installed by a professional, will they know the proper spacer to use or do they need to be told?
Also, is there such thing as a replacement "dam" that can be used for a correct installation?
Sorry to keep beating this subject to death, but I would very much like to have my windshield 'correctly' installed.  It always bothered me that I could previously see the butyl ribbon along the bottom of my windshield. 
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Jonesy

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Re: installing windshields
« Reply #7 on: April 01, 2007, 01:52:20 AM »
My glass guy did mine and also made sure the chrome trim went on. Thats why I had a guy who does this every day do mine.
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Flowjoe

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Re: installing windshields
« Reply #8 on: April 04, 2007, 04:00:28 AM »
The trick is (like with most of these sorts of things) to find a guy who knows older cars...and gives a hoot about his work.  Too many giuys are fast talkers and "adept" at doing new cars...would never admit to knowing next to nothing about old cars...and don't care if you will be a repeat customer.  It takes really good referrals from people you trust and a little trial and error to find quality automotive profesionals.

69Z28X33

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Re: installing windshields
« Reply #9 on: April 04, 2007, 11:49:50 AM »
How do you guys install windshields (and back glasses for that matter) so that they achieve a stock height and appearance?  I know that urethane is the best for sealing but I hear that it is difficult to get the height correct.  Butyl is  a pain but comes in a 3/8" bead plus no one seems to make/cary a pinch weld primer thta is compatible with butyl.

What did the factory use?

Flowjoe

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Re: installing windshields
« Reply #10 on: April 07, 2007, 10:11:35 PM »
How do you guys install windshields (and back glasses for that matter) so that they achieve a stock height and appearance?  I know that urethane is the best for sealing but I hear that it is difficult to get the height correct.  Butyl is  a pain but comes in a 3/8" bead plus no one seems to make/cary a pinch weld primer thta is compatible with butyl.

What did the factory use?
????????

jeff g

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Re: installing windshields
« Reply #11 on: April 12, 2007, 01:49:21 AM »
 Hey, folk's just joined CRG's forum I own a small auto glass shop in N.E. PA.  called First Class Auto Glass Inc. I have a dam that is 95% correct for all GM after they changed from rubber gasket set to "adhesive caulked glass" check your 69 Service manual. the only thing that is diffrent is that the factory's had a flap on one side of the dam that got embedded is the adhesive mine dosn't have the flap but since you can't see it unless the glass is removed it look's perfect, has the cloth type tape as well  i'm not too good with computers but I'll try and post some pic's of car's that I've done with it. and could offer my service's or set you up with a kit to do both front and rear glass.  give me a call or send me a e mail 570 344 8798 It will transfer to my cell if not at the shop

Flowjoe

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Re: installing windshields
« Reply #12 on: April 12, 2007, 03:10:23 AM »
Post some photos and details ...I'd be interested in seeing what you are doing.

jeff g

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Re: installing windshields
« Reply #13 on: April 13, 2007, 02:21:08 AM »

jeff g

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Re: installing windshields
« Reply #14 on: April 13, 2007, 02:57:43 AM »
hope the pic's are  ok. ( my buddy had to talk me thru the photo bucket deal on the phone) the glass in ang's camaro was done by the book . "V" notch bead 1/4 inch wide 3/16 tall. also note that on original cars that i've seen you will see a hint of the dam all the way around the glass. molding's are tight to the glass. no squeeze out on the inside. took about 3 hr's for both front and back