I am restoring a 69 Corvette convertible. The birdcage was dipped and clean and I have found inconsistencies in measurements from windshield top corners to door pillar post in back. Is there any place I can find measurements for the birdcage to verify what is bent?

 

There is a section of the AIM titled checking dimensions, I tried to decipher it maybe you will have better luck

 

My poor car is down to nuts and bolts. Everything is removed. When I was restoring the frame I did find out that the car had been in an accident on the driver side in the frame had to be straightened. Upon further inspection, I have found that the rear uprights are fine it's only in the windshield I have a problem. The driver side top windshield corner is 3/4" lower than the passenger side. It would be nice to find some measurements somewhere so that I can fix the problem before I start putting it back together.
No I have not fixed the rust yet. It only has minor pinholes two medium pitting, nothing that can't be patched. Luckily no need to replace entire sections.

 

IaRoadKill,
I have encountered this "issue" more times than I can count. The car was hit and fixed by some "BOZO" who got it "kinda close" and then slapped a windshield in it. THEN when it comes to adjusting the door windows...you CAN NOT adjust anything due to the windshield posts are laid "in"....and the window is where it is and you can not move anything without the door glass hitting something.

I would HIGHLY bet that the windshield is NOT an original "LOF" windshield...RIGHT???? Some aftermarket one, PPG, PILKINGTON, GUARDIAN for example.

And knowing that convertibles do not have the "luxury" of having an upper windshield frame to rear "B" pillar center beam for making it a T-top. In an accident...it does not take much to cause the "A" pillar or hinge post to lay "in"....and if the windshield got busted...and they cut it out...it allows the windshield frame to go further "in". Not so much that you will see it...but it does occur. And installing a windshield "after the fact" will still work due to the amount of urethane use in adhering it to the frame would not be so excessive that it would be noticeable...and if it was noticeable...they let it "fly" because they realized that they screwed up and did not want to correct the problem.

Think of it like this...at the top of the windshield corner in question...it is about 2 feet from the spot where the birdcage attaches to the frame...RIGHT?? And it would only take a slight bit of movement at the frame and birdcage to allow that post to lay in due to the angles and the distance from one point to the other. And this movement can often times NOT crack fiberglass. It will put it under stress...but not to the point of cracking it. And if it is allowed to stay in this "stressed" position...the fiberglass can actually begin to relax due to heat and age and not "pop" back when released....and find a new position it "likes".

With this all written. From personal / professional experience. I would not worry about it right yet. Simply I have not been able to find the dimensions you need. And I have found that I begin re-construction. Get the rear clip correct. The I install the doors and hinges and this is when I begin to re-assemble the doors and the windshield moldings and trim so I can install the pillar post weather strips and the door glass and it will aid me in making sure that if I need to pull the upper corner outwards...I do so...as long as I keep it within the adjustment specs of what GM provided in the door for the door glass adjustments. In your case...I would have to re-install the convertible top and use the rear vertical weatherstrip as a guide so I can get the door glass to fit correctly. Because this issue your are concerned with is mainly dealing with how the door glass will fit and adjust. The windshield will fit fine. BUT I still go in and use some butyl tape in small areas and install the glass and check to make sure the upper molding and clips work as designed...in conjunction with the side moldings.

When the birdcage is being installed in the frame. The number 1 and 2 body mounts can be shimmed to take some of this "lay-in" issue out..more shim in number 2 and less in number 1...but usually it does not change too much due to they are so close to one another....and the rigidity on the rocker channel in the birdcage is kinda stout.

WELCOME to my world. This is going to be a pain in the backside....and is going to be time consuming...but I know of no other way to get it to be correct and components adjustable as designed. Sometimes I have the "luxury" to have another Corvette in the shop that I can measure from because the windows fit perfectly and pull the windshield frame to it for "starters"...and adjust it from there before the new windshield goes in.

DUB

 

Thank you all for replying. I did figure out the AIM measurements for the height of the window corners it's off about three quarters of an inch. It took all afternoon to try and decipher but I think I have it figured out.

DUB, windshield is not original. I have it up on a stand and while sitting on the running board I noticed I could flex the windshield frame up and down and decided maybe I should just put it together and get the doors on before I worry about the windshield. I like your idea of adding an extra shim when mounting it to flex the frame a little bit, but I also noticed that I could flex the running board with my weight. So, I will wait until it's mounted to the frame which is straight then I will remeasure to make sure I know what really needs to be tweaked.

Thanks again to everyone. This is a learning curve and you guys are a lot of help.

 

So I got frustrated and took a break. But now it's time to get back to work on my car.
I fixed all the major rust issues and had it read it to be clean. After reading measuring the birdcage to find out if it is square, I have decided that the windshield is good. It's the rear columns that are off. I remember saying that I figured out how to read the measurements in the manual but in the past month or so I've forgotten how.
I am going to take some pictures and post them next

 

The main thing is to figure out the measurements...photo's will do really no good without a good reference. Post them if you like(needless to write)...but I know I can not comment on how something looks in photo if measurements are needed to be know...which I am sure you also know.

DUB

 

I asked the same question for my '73 coupe just yesterday... my AIM has no measurements though- can anyone post a scan of that page?