Corvette Forum : DigitalCorvettes.com Corvette Forums banner
1 - 20 of 20 Posts

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #1 ·
Before I do a repair on the frame of my 75, I thought I'd check to see what others might have done.

The car has been a continuous project for 10 years. Drive, upgrade, drive, upgrade, like most guys on this forum. All this time jackstands have been used to support the car when doing work. The front frame rails have started to bend in on the bottom due to resting on the stands repeatedly.

The car isn't pristine, so a NCRS frame repair isn't necessary, I was just going to weld on some thicker steel. If anyone else has done this repair and has some tips or suggestions, I'd be interested in hearing them.

I plan to support the car on blocks under the tires when repairing the frame.
 

·
Registered
Joined
·
3,100 Posts
Figure out how to make sure the frame is straight and square. Be a shame to weld and stiffen it and then find out it went crooked when you welded it. Maybe some box tubing measured and tack welded on?
 

·
Registered
Joined
·
1,016 Posts
The front frame rails have started to bend in on the bottom due to resting on the stands repeatedly.

Got any pics of this?
 

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #5 ·
I'll try and get some photo's in the next couple of days. It's only on the front frame rails right before the rails go up for the engine compartment. This car has been on jackstands a lot.

Dirtbuster and TimAT, thanks for the suggestions.
 

·
Registered
Joined
·
187 Posts
I'll try and get some photo's in the next couple of days. It's only on the front frame rails right before the rails go up for the engine compartment. This car has been on jackstands a lot.

Dirtbuster and TimAT, thanks for the suggestions.
I would be concerned that rust may have thinned the frame.
If this is that case, adding thicker steel to one section can put
undo stress on unstrengthened areas. Just be careful you are not
looking to treat cancer with a bandaid. I was gonna repair my 75
frame, but found too much hidden rot when I lifted the body and ended
up replacing it.

Good Luck :buhbye:
 

·
Banned
Joined
·
3,855 Posts
I would be concerned that rust may have thinned the frame.
If this is that case, adding thicker steel to one section can put
undo stress on unstrengthened areas. Just be careful you are not
looking to treat cancer with a bandaid. I was gonna repair my 75
frame, but found too much hidden rot when I lifted the body and ended
up replacing it.

Good Luck :buhbye:
What he said....no question....double check that roach really good....

:cheers: :cheers: :thumbsup:
 

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #8 ·
I uploaded photos, they will probably get approved tomorrow.

Yes, good point on the rust. But, I've had this car on jack stands a lot and it took place gradually. When I added the big block and the lakewood bellhousing, it seemed to accelerate.

It is a CT car, but there is no rust anywhere else, I've owned it since 97 and know it pretty well.
 

·
Banned
Joined
·
3,855 Posts
I uploaded photos, they will probably get approved tomorrow.

Yes, good point on the rust. But, I've had this car on jack stands a lot and it took place gradually. When I added the big block and the lakewood bellhousing, it seemed to accelerate.

It is a CT car, but there is no rust anywhere else, I've owned it since 97 and know it pretty well.

OK, here is esplain the devil of it,....seen it myself...in the Maryland area...

in winter, the high humidity and cold steel in AM act to condense moisture on steel car frames/unpainted surfaces and so it rusts with a constant moisture coating...IN A GARAGE.....don't ask...this is a very clear observace on my part some decades ago....Mom's old '63 F 85 sat there 25 years and rusted away to damn nearly nothing...in the garage....

so I have to run the caution flag up high on that one....gargae kept means little, to bare naked steel....given enough years/decades....just a door wich to airflow/humididty/temp may as well be wide open....

:thumbsup: :crazy: :WTF :cheers:
 

·
Registered
Joined
·
152 Posts
in winter, the high humidity and cold steel in AM act to condense moisture on steel car frames/unpainted surfaces and so it rusts with a constant moisture coating...IN A GARAGE.....don't ask...this is a very clear observace on my part some decades ago....Mom's old '63 F 85 sat there 25 years and rusted away to damn nearly nothing...in the garage....

so I have to run the caution flag up high on that one....gargae kept means little, to bare naked steel....given enough years/decades....just a door wich to airflow/humididty/temp may as well be wide open....

:thumbsup: :crazy: :WTF :cheers:
:agree:
Couple years ago after a few weeks of subzero temps we had a nice 40 degree day so I decided to climb under the car to work on whatever it was I was working on... Condensation was just dripping from the block and to a lesser extent the frame. Looked like I drove it through a rain storm.
 

·
Registered
Joined
·
1,016 Posts
I uploaded photos, they will probably get approved tomorrow.

Yes, good point on the rust. But, I've had this car on jack stands a lot and it took place gradually. When I added the big block and the lakewood bellhousing, it seemed to accelerate.

It is a CT car, but there is no rust anywhere else, I've owned it since 97 and know it pretty well.

I thought this sounded really odd......that's why I asked for pics.

A full frame setting on jack stands should not bend in the manner in which
you have describe..........ever.............with out an outside force being applied.
Like that of a 10 ton frame machine........like the others I feel you have
more serious problems.
 

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #13 ·
I thought this sounded really odd......that's why I asked for pics.

A full frame setting on jack stands should not bend in the manner in which
you have describe..........ever.............with out an outside force being applied.
Like that of a 10 ton frame machine........like the others I feel you have
more serious problems.
Okay, so if I have to cut out metal and weld in new, can I do it without removing the body? If yes, and suggestions on the procedure.

Just setting the frame on jackstands is similar to something called a zero-drop-height impact load. Or something like that, it's been a long time since I studied that. Anyways, it turns out if you release something from near zero height the impulse load is twice the weight of the object. It's been twenty years, but that's how I remember it.

Granted there is probably some corrosion inside, but it's not like I have holes rusted through.

Oh well, if there has suggestions, I'm willing to listen.

The good news is I'm not concerned about cosmetics on this car, only function.
 

·
Registered
Joined
·
1,016 Posts
Okay, so if I have to cut out metal and weld in new, can I do it without removing the body? If yes, and suggestions on the procedure.


The good news is I'm not concerned about cosmetics on this car, only function.
From the looks of the photos it just looks like the car has been "dropped"
on the jack stands numerous times.

If there isn't any excessive corrosion inside the rails and there is ample
metal thickness............ and considering your not concerned about
cosmetics only function..............I'd just leave it alone.

*******
But if you still wish to do something with it one approach would be instead
of cutting the section out....tack weld some tabs in the bent area a try pulling
the dent out with a 10 lb. snatch bar. When finished just cut the tabs off
and grind the welds smooth.

Of course you'll need to have the car on some sort of lift for best results.

********
You should be able to replace just the very bottom portion of the rail with out
having to remove the body or compromising any dimensional measurements.
(for lack of a better term) Just support the car at the shock mounts and
make sure it's level .....front to back ......side to side .....before cutting.
Take a level to the door sills.....top of firewall......and luggage area behind seats.
Don't make any attempts to move the car till your completely finished.


JMHO....Others may vary..;)
 

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #15 ·
Thanks SMYDA, good suggestions. One of my floor jacks might have been a bit unreliable. This took place over a lot of years and a lot of cycles on the jack stands. Being a CT car there probably is some corrosion inside, but compared to a lot of CT Corvettes that I looked at, this one was relatively good.

When you do your own work you break things sometimes.
 

·
Registered
Joined
·
79 Posts
Thanks SMYDA, good suggestions. One of my floor jacks might have been a bit unreliable. This took place over a lot of years and a lot of cycles on the jack stands. Being a CT car there probably is some corrosion inside, but compared to a lot of CT Corvettes that I looked at, this one was relatively good.
rtj, as already suggested, the damage that appears could be left alone, but it could also be repaired in various ways. There are frames in way worse condition holding together fine for street use. I raise my front using a scrap piece of pressure treated 4" X 4" post about 31 inches long. It fits below the lower control arms and between the spring pockets. My 2 ton jack fits under the post and the entire front raises without the control arms dropping much. With the tires off the floor about 6 inches, I put a jack stand between the spring pocket and lower ball joint on each side. A scrap 2 x 4 stub protects my powder coated control arm from direct contact with the stand. You might try raising your front end this way and supporting it under the control arm. I'd post a picture, but I broke my camera. I will be at Speedworld this Sat with some other vettheads. If you are not doing anything, stop by and chat. If you can come, send me a PM and I will give you my cell number and pit location. Saturday is the last race in the Summit Series for 07. Hope to see you there.
 

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #18 ·
rtj, There are frames in way worse condition holding together fine for street use. QUOTE]

Thanks Red, that is what I needed to hear. I should have "patched" it up when it first started, but never did. I bought a TIG welder a year ago and maybe this will force me to fill the argon bottle and get it set up.

Good luck in the finals at speedworld.
 

·
Registered
Joined
·
1,016 Posts
I bought a TIG welder a year ago and maybe this will force me to fill the argon bottle and get it set up.

Just a NOTE of caution in regards to Tig Welders.

In Bodyshops.....Tig Welders are not recommended because of the very high
frequency created by the machine. This frequency will fry most electronics.
This is why all Collision Repair is done with Mig Welders.......and you still have
to use caution.

You probably will not have a real problem with Older Vettes.........but if you
have any high dollar electronic equipment installed you may want to remove
it as a precaution before welding. Be sure to keep those ground leads
connected close to the weld zone. Might not be a bad idea to disconnect
any / all chassis grounds......as well as the battery.

Yes.........NASCARs are built with Tigs...........but that's before the electrical
is installed.....:thumbsup:
 

·
Registered
Joined
·
4,075 Posts
Discussion Starter · #20 ·
Just a NOTE of caution in regards to Tig Welders.

In Bodyshops.....Tig Welders are not recommended because of the very high
frequency created by the machine. This frequency will fry most electronics.
....:thumbsup:
Good point SMYDA. The car is pretty close to being gutted, but I do have a MSD6AL box, so I'll disconnect the battery.
 
1 - 20 of 20 Posts
Top