Frame rot!
Thread Starter
5th Gear
Joined: Dec 2012
Posts: 5
Likes: 0
Frame rot!
How do I fix this? I have a mig welder, could I weld on a big fish plate? I don't have a huge budget...
The rust is in front of the rear wheel on the drivers side.
http://flic.kr/p/dGxVF4
The rust is in front of the rear wheel on the drivers side.
http://flic.kr/p/dGxVF4
Pro
Joined: Nov 2012
Posts: 672
Likes: 0
From: Chesapeake Virginia
I'm not familiar with the '75 but on my '81 that particular area is one of the major strength areas of the frame. I'm sure it can be fixed but I would pull the body off for a couple reasons, first, to see how far the damage extends. and second, it would make the repairs much easier.
I don't think just a patch will be sufficient.
I'm sure others will chime in soon
I don't think just a patch will be sufficient.
I'm sure others will chime in soon
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
There's no cheap easy fix for that: You have to cut the frame rails and weld in new sections. Only way to do that is to pull the body, sandblast the frame, and start cutting & welding.
I thought I could get away with some easy welding from the bottom of the car, too, but had to admit reality. Here's the same area of my frame after I got the body off:
Only way to see what's good and what's not is to sandblast the thing. Here's the 'blasted frame with stiffening bars welded in to keep it from twisting when I cut the rails out:
SawZall is a great tool - cuts that frame like butter!
Cut frame showing all the rust holes that were visible only after sandblast:
New frame rail section clamped in place for welding. All the major Vette suppliers sell the frame rail sections in various lengths:
New section welded in:
This is the only way to do the repair right - there's no way you're going to repair that amount of rust damage with the body on the frame. My basic frame with the rust repaired and ready for paint:
Final assembly and almost ready for the body again:
Good luck with the project. If you're not wanting to pull the body, you might consider selling the car and finding something with less rust: You have a massive project ahead of you repairing what you have there...
Lars
I thought I could get away with some easy welding from the bottom of the car, too, but had to admit reality. Here's the same area of my frame after I got the body off:
Only way to see what's good and what's not is to sandblast the thing. Here's the 'blasted frame with stiffening bars welded in to keep it from twisting when I cut the rails out:
SawZall is a great tool - cuts that frame like butter!
Cut frame showing all the rust holes that were visible only after sandblast:
New frame rail section clamped in place for welding. All the major Vette suppliers sell the frame rail sections in various lengths:
New section welded in:
This is the only way to do the repair right - there's no way you're going to repair that amount of rust damage with the body on the frame. My basic frame with the rust repaired and ready for paint:
Final assembly and almost ready for the body again:
Good luck with the project. If you're not wanting to pull the body, you might consider selling the car and finding something with less rust: You have a massive project ahead of you repairing what you have there...
Lars
Last edited by lars; Jan 1, 2013 at 09:40 PM.
Drifting
Joined: Oct 2012
Posts: 1,524
Likes: 61
From: Medina Ohio
It's worse then you think. Mine looked similar, but I knew I needed a frame. It had already been "patched" from below. ...I considered just finishing the car the way it was, but decided to do it right and pulled the body for a new frame. When the body started coming up, the back half of the frame started going down. Never thought it was THAT bad. The body was basically keeping the frame together.
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
There's no cheap easy fix for that: You have to cut the frame rails and weld in new sections. Only way to do that is to pull the body, sandblast the frame, and start cutting & welding.
I thought I could get away with some easy welding from the bottom of the car, too, but had to admit reality. Here's the same area of my frame after I got the body off:
Only way to see what's good and what's not is to sandblast the thing. Here's the 'blasted frame with stiffening bars welded in to keep it from twisting when I cut the rails out:
SawZall is a great tool - cuts that frame like butter!
Cut frame showing all the rust holes that were visible only after sandblast:
New frame rail section clamped in place for welding. All the major Vette suppliers sell the frame rail sections in various lengths:
New section welded in:
This is the only way to do the repair right - there's no way you're going to repair that amount of rust damage with the body on the frame. My basic frame with the rust repaired and ready for paint:
Final assembly and almost ready for the body again:
Good luck with the project. If you're not wanting to pull the body, you might consider selling the car and finding something with less rust: You have a massive project ahead of you repairing what you have there...
Lars
I thought I could get away with some easy welding from the bottom of the car, too, but had to admit reality. Here's the same area of my frame after I got the body off:
Only way to see what's good and what's not is to sandblast the thing. Here's the 'blasted frame with stiffening bars welded in to keep it from twisting when I cut the rails out:
SawZall is a great tool - cuts that frame like butter!
Cut frame showing all the rust holes that were visible only after sandblast:
New frame rail section clamped in place for welding. All the major Vette suppliers sell the frame rail sections in various lengths:
New section welded in:
This is the only way to do the repair right - there's no way you're going to repair that amount of rust damage with the body on the frame. My basic frame with the rust repaired and ready for paint:
Final assembly and almost ready for the body again:
Good luck with the project. If you're not wanting to pull the body, you might consider selling the car and finding something with less rust: You have a massive project ahead of you repairing what you have there...
Lars
You are only seeing the "tip of the iceberg" looking at it with the body on. The frame rusts from the inside out. When you see a oz of rust on the outside, there is a lb of rust on the inside. I'm not referring to surface rust... I'm referring to rust-thru... NY Style.
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2nd Gear
Joined: Oct 2012
Posts: 2
Likes: 0
I have a 68 and had the same problem, frame rot on drivers side in front of rear wheel. Upon futher investagation, things got worse, also found the birdcage was rusted in the same area. You should check the birdcage in thes same area. I now have a major project on my hands. I purchased another 68 frame and will be repairing the birdcage.
Melting Slicks
Joined: Oct 2011
Posts: 3,453
Likes: 67
From: Midland Ontario
NCM Sinkhole Donor
How do I fix this? I have a mig welder, could I weld on a big fish plate? I don't have a huge budget...
The rust is in front of the rear wheel on the drivers side.
http://flic.kr/p/dGxVF4
The rust is in front of the rear wheel on the drivers side.
http://flic.kr/p/dGxVF4
Team Owner
Joined: Jul 2001
Posts: 61,414
Likes: 478
From: Here to make friends
St. Jude Donor '11, '16-'17
This showed up on my local craigslist. Seems like not a bad deal and could save someone a lot of work.
http://corvallis.craigslist.org/pts/3524405542.html
http://corvallis.craigslist.org/pts/3524405542.html
