Need Advice - Crack in The Frame

[maverickmk]

My '80 Corvette has a crack down the side and underneath the frame near the steering box. If I remember correctly, Mike from Cornfield showed a repair he did and he drilled a hole near the end of the crack before he welded it up - ?
Also, should I grind a small valley/groove into the crack before I stitch it up?
Any advice would be appreciated.

This is the side.


This underneath, it is a complete run.


I can take more pictures if need be.

 

[Old Iron]

When cracks form in frames or tubing, they do so because it has rusted from the inside out.
You can cut the bad section out put an internal plate on the inside and then drill a 1 inch hole on each end of the frame only so you can make a plug weld to the internal plate. Put a new piece of metal where you removed the rusted part and weld it.

 

[earthman]

I know you like this car Mav but the other side has to be ready to go as well.
The upside is this thing has excellent doner material.
I'm building a single seat center steer speedster out of my '88.

 

[Bamamav]

Might be ahead to look for a donor car with a good frame. See them all the time on CL.

 

[BlueNorther]

almost all corvette frames are rusted somewhere, had a 64 and sold it as the frame was like swiss cheese. I read some where that you can still by bare frames from Chevy and the price is not totally nuts.

 

[soltz]

DIY

Ain't we do it yourself's [S
How tuff could it be [

 

[23crate]

hmm could be full of hidden nastys',, snakes, gun totin terrorists, Cling-ons, an unexplained chunk of c4 from a hidden previous owners secret stash....
or just a hidden stash ,,,,

my advice as a body man::

get out your grinder , grind a valley as you put it , in the crack, once you have "veed" the crack and get it the depth of the frame wall , then you may have some clarity on weather its full of rust or not.

could this the crack associated with the twist or torq of the motor ( stress crack ? ) nearer the front of the rail.

if its just a stress crack then vertical up weld stitching in a continual figure 8 pattern. . when you weld the underside (im guessing from your pix) then weld similar but keep your weld heat to a lower limit and beware the puddle will drop if your not watching it ....

Luck
crate

 

[maverickmk]

This is a stress crack from the steering box. There was quite a bit of deflection in the frame when turning the wheel. I have found a plate that is manufactured by a company that races these C3's. The reason they started making them was because they were getting the same cracks as I have from the steering box. They have been abusing it for a few years with one of their plates and no cracks yet. I am looking to find a frame, sand blast it and weld in a bunch of gussets, etc to strengthen it, then once that is done do a frame swap in a couple of years. Just looking for a good fix for now.

 

[BlueNorther]

here you go biggest Corvette re-cycler in the world:

http://www.tracyvette.com/frames.html

 

[dutch]

I`d just grind the weld in a V and clean up the surrounding area. weld it and cap it. Just make sure if you weld a cap over it ,to use plug welds through the cap and not weld a seam across the frame, lenght direction only.

 

[23crate]

I`d just grind the weld in a V and clean up the surrounding area. weld it and cap it. Just make sure if you weld a cap over it ,to use plug welds through the cap and not weld a seam across the frame, lenght direction only.

what he said..

do remember early 90's Cherokees, had a similar problem at steering box.
Chrysler supplied a repair kit - two plates with holes for plug welding, longer steering box bolts, and a how to guide. took about 4 hours to do
the how to said same, weld cracks , smooth , weld plates over and plug weld .

plates were oblong with a 45 corner and bottom front notched, this allowed for welds over different areas . other than not welding around a corner, the repair was pretty straight forward.

 

[Torch]

rust=hydrogen embrittlement

You might stand a better chance of the weld not cracking back out if you use oxy acetylene to weld it back up.
Mig cools pretty fast and doesn't give the metal a chance to anneal.

 

[Blue Eyed Devil]

The sky isn't falling. People have welded cracks in frames for as long as there have been frames. Drill a hole at the end of the crack to stop it from running, V it out and weld it up. No problem. Put a fish plate over it if you are that concerned. Done. Hot rodding 101...

 

[05snopro440]

rust=hydrogen embrittlement

Huh? [S

Hydrogen can be produced by rusting, and some materials are susceptible to hydrogen embrittlement when welding. However, those two are not exclusive. Hydrogen embrittlement requires certain conditions, including dissolved hydrogen in the steel. That's highly unlikely in this case.

 

[forbigpicture]

Huh? [S

Hydrogen can be produced by rusting, and some materials are susceptible to hydrogen embrittlement when welding. However, those two are not exclusive. Hydrogen embrittlement requires certain conditions, including dissolved hydrogen in the steel. That's highly unlikely in this case.

Must have skipped class that day.....[S[S

 

[05snopro440]

Must have skipped class that day.....[S[S

[P

 

[oldmanb]

That's an easy fix, we do that stuff daily. I doubt though that's it's thick enough to v-out. Clean it up really good on both sides of the crack ,if you can't get to the inside run your o/a torch over it on with the oxygen turned up it bit, that's blow most of the dirt/crap out. You can't do any worse then the factory welding on the rest of the frame, go at 'er !

 

[Dr Crankenstein]

Since it's back on top... how did this turn out for you, Mav?

.

 

[maverickmk]

Since it's back on top... how did this turn out for you, Mav?

.

My regulator took a crap on me. I got a new one but it has stalled the project for now. Hopefully I can find some time soon to get back on it.

 

[sgtpontiac]

I agree....

The sky isn't falling. People have welded cracks in frames for as long as there have been frames. Drill a hole at the end of the crack to stop it from running, V it out and weld it up. No problem. Put a fish plate over it if you are that concerned. Done. Hot rodding 101...

Could a, should a, would a....you can speculate about it but this crack is common...drill holes at either end of crack, v out and weld it....you can plate it too if you feel the need for extra insurance....personally I would but not everyone does...my 62 Chevy convert developed a crack similar near the steering after the frame was pulled from a previous accident before I bought it...that's how I fixed it when I noticed the steering was getting vague and found the crack...