[pippintook]

I have the front and rear glass out of my 78 Trans Am. Car is in epoxy and window channels are nice and clean/epoxied. I cant get it to a glass shop so was thinking of installing the front and rear glass myself.

I thought this was a good video on doing a windshield install on an older GM musclecar
https://www.youtube.com/watch?v=aY1bLFKbRuA

My possible parts list would be
------------------------------
1. 3M Window-Weld Sealer, http://www.summitracing.com/parts/trm-8611/overview/ $16
2. Dual Cup Suction Lifter, http://www.harborfreight.com/dual-cu...ter-46134.html $16
3. 'DOW U-418 QUICK CURE AUTO GLASS PRIMERLESS URETHANE ADHESIVE' $22
http://www.ebay.com/itm/2-TUBES-DOW-..._Tools&vxp=mtr
- Approximate parts cost = $54

Possible Steps to install glass
-----------------------------
1. Using Suction cups (and assistant) dry fit glass. Using small blocks (at glass base) get glass centered/squared in frame.
2. Once glass centered, install two pieces of 4-5" masking tape that run from bottom of glass to cowl. Cut the tape at base of windshield with razor. Leave tape on cowl and glass. these tape pieces will be 'witness marks'.
3. Using marker (sharpie?) - go round entire glass and mark glass to show where body/glass channel is. basically these sharpie marks will be where to place dam. The dam will go just to outside of these marks.
4. remove glass from car.
5. flip glass over and prepare to install dam. using the '3M Window-Weld Sealer' in 5/16" thickness install the dam around entire perimeter of glass. Start at base of windshield and use 'sharpie' marks. The dam would be installed just to outside (ie.towards glass edge) of 'sharpie' marks.
6. cut tip of 'DOW U-418 QUICK CURE AUTO GLASS PRIMERLESS URETHANE ADHESIVE' into a 'v shape'
7. install a bead of U-418 URETHANE ADHESIVE around entire perimeter. The bead of urethane would be around 3/8" thick and would run beside the dam ...though the bead would also be partially on the dam.
8. install glass (with assistant)...align tape on windshield with tape on cowl...
move glass very slightly with suction cups as required to square/center

Has anyone used this approach of 3m window weld dam and U-418 adhesive?
Should the the 3M window weld dam be 5/16" thick? Any or tips/advice is appreciated.

[Toms bird]

The guy in the video needs to read the technical data for that product. It's primerless to glass if it has a frit band or factory black edge. If like most 60s car it came without one you need use their black primer on the glass. Not to make it adhere but because the urethane is not uv stable and breaks down in time from the sun.

[DOC]

When we laid the bead of urethane on mine, it was about an inch high into a skinny point and compressed it down to about 3/8" and it ended up about a 1/2" wide all the way around.

[Toms bird]

I just reread what your trying to do. You should decide if you want to install your glass with butyl or urethane. What i mean is your using butyl like a dam but your using butyl primer on the body. If your counting on the strength of the urethane use urethane primer on the body. If you want to use the butyl to seal it use it press the glass in good and back fill with the urethane. Personally I would put it in like the factory which was full urethane. Don't worry about the dam it take up to much of your bonding area. You just have to be neat. That urethane is not the best for that because it not a high viscus It'll let the glass sink too low unless you use some small foam blocks on the outside edge of glass in corners try and stay out of urethane area. I don't know if that helped or confused you more.

[pippintook]

Thx for replies. There does not seem to be a ton of great detailed info on installing glass in 2nd gen f bodies. Most guys it seems get their glass installed - perhaps, rightly so...as it does appear to be a process that can be easily screwed up by poor installer and/or poor tools/materials/process used.

I thought the youtube video was pretty good and guy (he says he runs First Class Auto Glass in scranton, pa) seemed to be experienced and using a good process. In the video he uses the a dam (Im not sure what is the exact dam product and thickness but it appears to be like the 3m window weld and around 5/16" thick?) and urethane together. It appears he puts the bead of urethane just beside and also partly on top of the dam.

I thought the dam with the urethane looked like a good process. Perhaps, this dam/urethane process is a bit easier for a rookie installer.

Also, say the dam was 1/4" or 5/16" thickness (im not sure what it actually is?) Id think the dam with a bit of urethane on top would appear to help keep final installed height around 3/8"..should final installed height should be around 3/8 for 2nd gen f bodies?

I dont have any preference for any particular method. Im just trying to figure out if this guys method or what other methods/materials guys have used for 2nd gen glass installs...and hopefully this method can be followed by rookie installer.

Maybe the best method is just to use a bead of urethane like Doc did. Doc - to get a nice pointed tip for the bead did you put a v tube cut in the urethane tube tip ? It sounds like Doc ur urethane bead would be around 1/4" wide (as it compressed/increased to approx 1/2" width when installed) - is that correct ? Did you use a specific urethane? Where exactly did you install the bead?
With the bead alone did you use any spacers? I have read where the installer can use spacers on the glass. I assume you place the bead ontop/around the spacers and these spacers help keep installed height correct?

[DOC]

Used 3m Urethane 08693 in a big caulk tube and cut a V in the tip and held the tube at a 90 degree angle and applied it. It basically comes out the side of the applicator tip vice the tip. Didnt use depth spacers. just brackets/.blocks on the bottom to prevent it from sliding down. we kept it centered in the window channel and set the trim in there to make sure it was deep enough. If not deep enough your trim will not snap onto the clips when dry. Speaking of clips, make sure the molding clips are installed before the windshield otherwise it can be a pain. do it in the shade so you have a little time to move it around if need be. also key note is to keep door windows down an inch or so for a day while the urethane cures.

[pippintook]

Doc - thx for info
.
I thought this was interesting (from http://www.chevelles.com/forums/showthread.php?t=378342

This discusses how GM installed glass...

.
"...John Hinckley: "GM never used butyl tape or anything like it to install windshields or backlites. Period.

The body opening flange was coated with black silane primer using a flow-brush 30 minutes prior to installing the glass, and all the reveal molding clips were installed to the Body Shop-installed weld studs.

The glass was placed on a powered rotating fixture, inside edge up, retained by suction cups.

The glass periphery was cleaned using a solvent, dried, and a different silane primer was applied.

A fabric-reinforced self-adhesive foam rubber "dam" was extruded and applied to the glass just inboard of where the Thiokol adhesive would later be applied; the purpose of the "dam" was to contain any Thiokol "squeeze-out" so it wouldn't show from the inside past the edges of the interior garnish moldings after the glass was installed to the body.

After dam application, pumpable Thiokol adhesive (with a pyramid-shaped cross-section created by the dispensing tip) was applied adjacent to the dam, all the way around the glass.

Lower glass supports were fixture-located and screwed to the cowl, and rubber spacer blocks were glued to the opening flange. The spacer blocks set the height of the glass relative to the body to ensure a good fit of the reveal moldings.

The prepared windshield was removed from the rotating fixture, installed in the body opening, and pressed down against the rubber spacer blocks; wooden tonque depressors were used to "paddle" the Thiokol around the edges at a 45* angle from the top edge of the glass to the bottom edge of the body opening to ensure a continuous seal all the way around the glass.

Reveal moldings were installed.

That was the plant production process, and explains what is sometimes described as a "rope" being found when an original windshield is removed - the "rope" is the fabric-reinforced rubber "dam" that was applied prior to applying the Thiokol adhesive.

If you'll look in Section 4 ("Fixed Glass") in the Fisher Body Service Manual, you'll see exactly the same process for windshield replacement, except the "dam" wasn't included with the Service kit - masking tape was used instead to control "squeeze-out".

The Thiokol installation passed the Federal MVSS windshield retention tests, and contributed substantially to the body's torsional stiffness; it also helped the structure pass the roof crush test. It's illegal to replace a windshield with butyl tape, although some glass shops do it as a less-expensive short-cut method instead of doing the job right...."

[pippintook]

I ended up getting a glass guy to install my front and rear glass on my 78 TA. I assisted a little and took a few pics

These were the materials and tools used:
- Sika Aktivator Pro
- Sika primer 206 g+p
- SikaTack Drive Adhesive
- Dewalt 18-Volt Adhesive and Caulk Gun

Note, the car windshield channel was cleaned and painted prior to install. As I recall..the basic steps followed were

1. windshield placed on stand
2. apply Sika Aktivator Pro to bonding area of windshield
- note, painter's tape was placed on car to help keep the Aktivator/primer from getting on dash etc
3. apply Sika primer 206 g+p to bonding area of windshield
4. apply Sika primer 206 g+p to bonding area of car windshield channel
5. remove painters tape as required from car
6. note, special cut used on SikaTack Drive Adhesive tube
- this cut lets the tip rest on the glass and as tube is moved the
adhesive comes out the side of the tip and forms a pyramid shape
7. apply adhesive to glass with Dewalt 18-Volt Adhesive and Caulk Gun
8. fit windshield on car
- two person job using HD windshield suction cups

I ended up getting a new front windshield and reused old rear glass.

I am attaching some pics

[pippintook]

Pics applying primer

[pippintook]

Tip cut used on Adhesive tube

[pippintook]

Pics applying adhesive

[pippintook]

Pics after applying adhesive

[pippintook]

We test fited the window chrome and it looked ok. The cost to install was $70 for front and $70 for back and new front glass was $150. I thought price was very reasonable. If doing your self...I would think good prep is important, channel and glass should be real clean...Aktivator and Primer placed on windshield..laying a nice even bead of adhesive could be a bit tricky.
.
I will post some more pics after the install.