Ok guys, i just got finished removing the rear window back glass from my 68SS. The glass looked like crap and was impossible to clean in the car. Also the package tray needs serious work and the gutter around the glass was starting to rust. How many have removed the rear glass and do you have any advice on reinstalling it?

i have the rubber spacers that go at bottom and i intend to use the 3M window weld urethane sealant. I'm also going to grind out all the rust and use some POR-15 rust remover to coat the channel in the prevent rust in future. how thick a bead of the urethane should i lay down when i drop the glass in? i want to make sure i have enough to seal but not squish out everywhere and make a d*%# mess.

i also want to tint the window before i drop it back in. Any advice appreciated, Thanks!

Here's an article on setting the window. Be sure you don't run the tint all the way to the edge of the glass where it bonds to the car! You don't want the window tint film being what is holding the glass in!

http://www.camaros.net/forums/showthread.php?t=13191

Brian

Thanks alot Martinsr, very good article. So I guess i will pickup the butyl tape at the auto parts store today.

The preparation of that channel is going to the key to a long lasting repair. Just brushing some POR isn't going to do it. Sand blasting it out and epoxy priming it is what I would be thinking about doing.

Brian

Well i dont have a sandblaster and dont want to further damage the paint. i was going to use my air powered 1/4 sander/grinder with some aggressive wheels and take it down to the bare metal inside the channel. you think i should spray epoxy paint instead of POR?

I could tape off around the channel and spray the paint from the gun to coat it well. i just thought the POR would be better.

Well I ended up doing it twice (don't ask), but I will share my wisdom!..

First off, use the butyl stick tape stuff, do NOT use urethane. I have someone that had glass shop experience to back me up on this. Urethane BONDS, it's fine for new cars, but the old cars have more give to them and the glass needs some movement, the stick tape stuff allows this and makes subsequent removals MUCH MUCH EASIER if need be.

IMHO you need 3 people for reinstall. That's what worked for me. One person on the inside to hold the weight of the glass while 2 people on the outside (one on the left, one on the right) do the fine tuning to move the glass right in position on the blocks and to make sure there is a uniform gap between the edge to the glass the the pinch weld area of the car. Once in position it was 1-2-3-LOWER! There's no turning back once down, that tape is supppppper sticky.

But to back up, here's what I did on my '70 coupe. It was very rusty at the bottom, especially the corners. Someone had previously pieced in some metal before from a rust-out repair. For the most part the area was structurally sound, just rusty and had pin holes. I sanded and scuffed and sanded some more (no sand blaster available for me). I used "por patch" to fill in the holes in the lower corners. Got everything smooth then went over the area with POR-15 silver (the silver supposedly is better as it contains metal fragments). Then after I let that totally cure for a couple days (yes, dont' rush this), then I took a scotch brite pad and scuffed where the stick tapes was to go down so it has something to "bite into".

I put down the butyl tape with the one end starting up towards the top of the window. Work your way around using a piece of the slick paper covering that seperates the roll of butyl (this works as it won't stick to you as you lay it down). Work all the way back to where you started and "butt" the ends together to form a water tight seal. Before you smack down the glass make sure it is ULTRA clean.

Once set in place, use your PALMS to press down on the glass to make it "kiss" the butyl and make a seal. Don't press with fingers and it puts stress on glass corners. If it doesn't totally contact the glass all the way around, don't worry, go back into the car and use a dental pick to stretch the butyl carefully up to the glass to make it stick to it.

Take your time!!

BTW, I tried using the Au-Vee-Co brand moulding clips for the stainless steel that goes around the glass, they don't fit right. the Genuine GM ones from Year ONe fit great.

Thanks alot Joe, sounds like some good advice. I'm nervous as hell about putting it back in so to say that "I'm taking my time" is an understatement. I'm barely moving at all. just spent a few hours tonight cleaning the sanding the channel. trying to decide between POR treatment or epoxy paint. where did you get the butyl tape? can NAPA order it?

Thanks alot Joe, sounds like some good advice. I'm nervous as hell about putting it back in so to say that "I'm taking my time" is an understatement. I'm barely moving at all. just spent a few hours tonight cleaning the sanding the channel. trying to decide between POR treatment or epoxy paint. where did you get the butyl tape? can NAPA order it?

I believe (this was like literally close to 10 years ago) I got it thru year one. But most Automotive paint supply places should have it. I *think* I used the smaller size. There's a 5/16" ? and a 3/8"? tape (the larger one is for major rust out problems). Hopefully someone can chime in.

The rear glass is thick (even new replacement glass) so you need the 5/16" butyl tape for it. NPD sells the 3M tape if you can't find it anywhere else. 5/16" is necessary to get the trim to fit correctly after the glass is in. Install the molding clips AFTER the glass is in. Be sure to trial fit the glass before installing the tape. Use the setting blocks that come with the tape to rest the glass on at the bottom then tilt the top into position. During the trial fit after centering the glass in the opening put a piece of masking tape on the bottom of the glass running onto the body. Make a vertical mark on it with an ink pen then cut the tape at the glass edge with a knife. Now you have alignment marks to use when setting the glass. A big help for tilting the top of the glass into position is to get one of those $4 suction cups at the auto parts store.

3M makes a pinch weld primer to use with the ribbon. Comes in small bottle. For neatest job, put ribbon on very outside of glass. In my opininion (at least on a 70) putting the clips on after the glass is in would be extremely difficult.

In my opininion (at least on a 70) putting the clips on after the glass is in would be extremely difficult.
It's not hard at all. I've done it both ways and I don't find it difficult to insert the clips after the glass is in place. They just slide in vertically (perpendicular to the glass surface) over the studs. I'm not talking about the studs themselves. On the other hand, once during installing glass with the clips already in place, the butyl tape contacted one of the clips and stuck. Things went to crap from there. That tape doesn't like to be removed (intact) from anything.

1/4 inch butyl tape or 5/16? which will make the molding fit the best?

Martin says 1/4, Von says 5/16. Any thoughts, I'm going to pick some up this week and hopefully put the glass in over the weekend. what size is on it from the factory?

its a big gap, 5/16 sounds like it would work the best.

I've installed rear glass 3 times on two different cars with 5/16" tape and the trim fits perfect. I didn't know 1/4" tape was even available. The only 3M choices from Chevelle parts vendors are 5/16" and 3/8". The 3/8" is needed for replacement windshields since they're thinner than original. Replacement rear glasses (that I've seen) are the same thickness as orig.

1/4 inch butyl tape or 5/16? which will make the molding fit the best?

Martin says 1/4, Von says 5/16. Any thoughts, I'm going to pick some up this week and hopefully put the glass in over the weekend. what size is on it from the factory?

its a big gap, 5/16 sounds like it would work the best.

No where do I say using a 1/4" on these cars. Here is the qoute from the "Basics".

"You can get the butyl tape in ¼”, 5/16” and 3/8” in diameter. I have found that the 5/16” is the most common with ¼” being used in late model cars on the quarter windows. The 3/8” is rarely used and can really get you in trouble. If you set the glass with the 3/8” you may find that it is impossible to install the moldings because the glass is too high!"

I do mention that the 5/16" will smash down to a quarter inch, but that is it.

Something like a PT Cruiser or Ford Truck that has "bolt in" quarter windows uses 1/4", most all others would be 5/16". As mentioned, when the glass is being replaced with NEW REPRO glass, the NEW REPRO glass may be a little thinner (as all REPRO parts are "similar" to original) and 3/8" is needed.

Brian

The only sure way to keep the rust from returning is to sand blast the channel. Do not rely on something like POR-15 to do the job. Besides, the stuff is not meant to be used under a top coat. Get yourself a cheap sand blaster, tape off the inside, and blast the channel. Chances are pretty good that once the rust is gone, there will be some metal work to be done. Follow that up with a coat of primer, sanding surfacer and top coat. It's gonna be tough to blend the paint from the channel into the roof, quarters and deck so you may want to consider waiting until you are ready to paint the whole car. Once that is all done then take a look at installing the glass, using the butyl tape method and six hands.

Tom

Sorry Martinsr for the misunderstanding. 5/16 its is.

Today i took it down to the bare metal using an air powered abrasive wheel. the pinch weld is in good shape just needs to be worked with some primer and sanding.

The package tray center is completely gone so i had to cut it out. looks like the project is going to take longer than expected. i will pick up some sheet metal and begin replacing it. as far as painting the channel and blending paint goes, I'm just going to fix the rust, paint the channel up to the top where the molding stops. hopefully it won't look to bad. I guess there will be a thin black ring just around the chrome molding.

Ok, so incase you guys are wondering just what it looks like and what I'm dealing with here you go.

http://gallery.me.com/ryan.boone#100008

6 pics of the rear window and my progress.