Birdcage Rust - Thoughts on Approach?
Thread Starter
Burning Brakes
Joined: Feb 2002
Posts: 752
Likes: 31
From: Melbourne Australia
Birdcage Rust - Thoughts on Approach?
Hi, I'm in the process of a body off resto. Removing windscreen has uncovered rust in the lower corners...usual places, however the birdcage is in otherwise excellent condition. 
Rather than removing the entire front clip, I plan to cut the upper fender corners off, repair the rust damage and then bond and glass the corners back in. See pic ...
Has anyone tried this approach? Seems easier than removing and reinstalling the front clip if no other reason to do so.
TIA
Joe
Rather than removing the entire front clip, I plan to cut the upper fender corners off, repair the rust damage and then bond and glass the corners back in. See pic ...
Has anyone tried this approach? Seems easier than removing and reinstalling the front clip if no other reason to do so.
TIA
Joe
Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
on a 69 427 matching, I'd probably do it right, actually , on my non matching 76, I'd probably do it right too, not that I havent bubba'd but if I have a choice, time and funds, I dont. I think body off means front clip also
Thread Starter
Burning Brakes
Joined: Feb 2002
Posts: 752
Likes: 31
From: Melbourne Australia
Oldalaskaman... you make a good point. I've done a few body offs including front clip removal. However I've only ever removed a front clip to replace it or repair extensive birdcage rust.
This car has excellent front clip fit with good door gaps, and these are often difficult to get right with a front clip removal....so my thinking was to minimize the risk and not disturb anything that was still good.
I'll need to repair quite a few fiberglass cracks from 40+ years of use and will be repainting the car... so cutting off these corners and grafting them back on doesn't seem like a big issue.
I wonder if anyone has done this before and was it satisfactory?
Joe
This car has excellent front clip fit with good door gaps, and these are often difficult to get right with a front clip removal....so my thinking was to minimize the risk and not disturb anything that was still good.
I'll need to repair quite a few fiberglass cracks from 40+ years of use and will be repainting the car... so cutting off these corners and grafting them back on doesn't seem like a big issue.
I wonder if anyone has done this before and was it satisfactory?
Joe
Racer
Joined: Jan 2007
Posts: 427
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Check this forum or the paint and body forum as I think I saw where someone had cut the tops off to get to the lower windshield area.
Out of experience, only disturb what you need for this type of repair, a total removal for some 'select' rust surgury is not required in my opinion.
Good prep and clean up with a solid weld will bring a satisfying 'birdcage' repair.
Good luck.
Out of experience, only disturb what you need for this type of repair, a total removal for some 'select' rust surgury is not required in my opinion.
Good prep and clean up with a solid weld will bring a satisfying 'birdcage' repair.
Good luck.
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
My car is not a numbers matching car or a high end car I cut the corners of the surround/fenders off as described in a Corvette Restoration book that I have. I cut out the rust and fabricated replacement patches and mig welded them in place.
[IMG]http://i839.photobucket.com/albums/zz313/roco71/memorystick05
7.jpg[/IMG]
[IMG]http://i839.photobucket.com/albums/zz313/roco71/memorystick05
7.jpg[/IMG]
Le Mans Master
Joined: Aug 2010
Posts: 9,272
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Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
My car is not a numbers matching car or a high end car I cut the corners of the surround/fenders off as described in a Corvette Restoration book that I have. I cut out the rust and fabricated replacement patches and mig welded them in place.
[IMG]http://i839.photobucket.com/albums/zz313/roco71/memorystick05
7.jpg[/IMG]
[IMG]http://i839.photobucket.com/albums/zz313/roco71/memorystick05
7.jpg[/IMG]
To the OP : the rust you are seeing is only the visible part. It signals that water has entered the birdcage in the A-pillars. I bet there is more.
What you have to understand is that the firewall covers a large part of the A-pillars. You will not be able to remove that with just sawing the top of the fenders off.
Take the front end off, take the firewall off and then you can have a go at it.
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Le Mans Master
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From: charlotte north carolina
if you decide to cut the corners off the fenders, make a template for the vertical and horizontal position before you cut. also, get some strips of fiberglass and use them as 'bonding strips' when you reassemble the corners.
Thread Starter
Burning Brakes
Joined: Feb 2002
Posts: 752
Likes: 31
From: Melbourne Australia
JNB.... thanks, I'll certainly use bonding strips.
Belgian.... I have done 4 front clip removals and one firewall in the past so I really do know how much work there is. I think I caught this just in time. There were no holes in the rusty sections until I started to scrape and poke at the rust. The #2 body mounts are pristine... no evidence of water. I think I'll go with Roco's approach since the rust is so minor.
Interestingly, there were foam rubber cushions in the windshield corners which I believe retained water and initiated the rust. Looked like factory items.
Roco... great pictures... thanks! They help me locate the fiberglass upper fender support that's riveted to the A pillar...
Joe
Belgian.... I have done 4 front clip removals and one firewall in the past so I really do know how much work there is. I think I caught this just in time. There were no holes in the rusty sections until I started to scrape and poke at the rust. The #2 body mounts are pristine... no evidence of water. I think I'll go with Roco's approach since the rust is so minor.
Interestingly, there were foam rubber cushions in the windshield corners which I believe retained water and initiated the rust. Looked like factory items.
Roco... great pictures... thanks! They help me locate the fiberglass upper fender support that's riveted to the A pillar...
Joe
Racer
Joined: Jan 2007
Posts: 427
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Right on Roco 71! those are the pictures I saw. Excellent repair.
Good luck jyounane, read up on fiberglass repair, a wide 'bevel' with back support will get you back to square one.
If I am not mistaken, I think there was plastic 'troughs' that would take the water down to the sides of the A /hinge pillar out of the way.
Good luck jyounane, read up on fiberglass repair, a wide 'bevel' with back support will get you back to square one.
If I am not mistaken, I think there was plastic 'troughs' that would take the water down to the sides of the A /hinge pillar out of the way.
Thread Starter
Burning Brakes
Joined: Feb 2002
Posts: 752
Likes: 31
From: Melbourne Australia
Korevette.... I have a lot of experience with C3 and C4 fiberglass repair, I think that will go ok.... I always use a wide bevel and generally rivet some small straps to hold things in place.
There are metal troughs for the water with a rubber trough below which forms the lower part of the windshield pillar seal.
However the cushions I mentioned earlier sat in the metal troughs and prevented the water from running out.
joe
There are metal troughs for the water with a rubber trough below which forms the lower part of the windshield pillar seal.
However the cushions I mentioned earlier sat in the metal troughs and prevented the water from running out.
joe