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nicolas
05-25-2005, 06:42 AM
Hi,

Been a while...
I picked up a mint car with a right front damage. Its unibody.
Have removed the external fender and trying to straighten the inner fender and re-enforcing rib. There's a couple of folds to the forward-most, 12 inches or so of the re-enforcing rib, as well as some smaller creases to the inner fender. (It looks as if it was designed to buckle here and not take the rest of the rib/inner fender with it..)

What's the most appropriate way to beat this back/straighten this, bearing in mind that its structural;

Hot or Cold Beating?

I was also thinking to tie a winch to a tree and heat the damaged areas slowly to pull this thing back as much as possible, and then beat away...

The car drove ok (before I started taking things off) fine and "crude" measurements do not show any major mis-alignments.
I figure I would like to straighten as much and see...Ultimately, I would take it to pros for any minor adjustments.
Repair panels are available, but would entail alot more removal, the dash etc...

regards,

nick

gator 1
05-25-2005, 07:43 AM
try this web site. Its set up just like metalmeet but based on auto body and repair. www.a2zautoforums.com Gator

Stempy
05-27-2005, 06:38 PM
Nick If you are dealing with a newer late model unibody automobile you need to proceed with caution! Ther are many different very hi-tech metals in later cars. A couple of the ferrous variety that come to mind are HTS and HSS steels. They are not designed to retain their manufacturers characteristics when heated above a certain temperature. Many are not designed to be repaired after a certain deformation point. The manufacturer has the correct repair procedures. As far as pulling out the first foot of damage first by whatever means and using heat, well you are looking for trouble. Most late model unibody cars are built to very close tolerances! There is usually very little suspension adjustment. That means control points need to be in the correct XYZ locations. I would not let a pre-pulled (I use the term very loosely!!!!!) auto on the property. The liability is huge! Not to mention the pride factor! Unitized structure repairs are not for the back yard operation. We use a Globaljig fixture bench from Italy. Cost new 38K. Precise to within a MM. In the food chain when someone gets their hands on that car after it leaves you and if it is involved in a future collision and it lands in a reputable shop and these sub-standard repairs are discovered and that results in, or contributes to, the total loss of the vehicle! Well you had better have your assetts well protected! Proceed with caution here!! Do not underestimate the skills or equipment needed to correctly repair a modern unibody automobile! Jon T

rsanter
05-29-2005, 12:50 PM
I would concider taking the car to a frame shop as one option. I have fixed a couple of cars and saved money by doing the teardown and assembly myself and let the shop do the pull.

another option would be for you to do the pull yourself by using either the tree method or fabricate a makeshift frame jig yourself. if you chose this option you will need to to get ahold of the frame specs so you can measure and be sure you get the car back to where it needs to be.

third option would be to simply cut out the bent sections and replace with good stuff. I have done this several times to save vintage cars with alot of bend to them. I simpls trace back to where the metal looks good and separate the car at the factory seams. then just weld in a replacement section from a donar car. done right it will be safe and nearly undetectable. you will need the frame specs for this one as well. while this I belive is a good option for the 60s to early 90s cars, some of the newest of cars could be a problem. what are you working on?

seajays
05-29-2005, 04:23 PM
Try finding a Bodyshop that has a Genisis Electrinic Frame Measuring system. This is a very accurate devise to get it back to where it should be. Don't try to pull it yourself!.I am a bodyman and would not consider doing this without good measuring equipment. At least get them to pull it for you to get it right.

sevt_chevelle
05-30-2005, 09:22 AM
third option would be to simply cut out the bent sections and replace with good stuff. I have done this several times to save vintage cars with alot of bend to them. I simpls trace back to where the metal looks good and separate the car at the factory seams. then just weld in a replacement section from a donar car. done right it will be safe and nearly undetectable. you will need the frame specs for this one as well. while this I belive is a good option for the 60s to early 90s cars, some of the newest of cars could be a problem. what are you working on?

Personally this is not an option.
Even if you cut out enough metal to where it looks good you still have stored engery in that car. You need to pull the metal back out to orginal specs then you can remove the damaged metal and replace.

I do collision repair for a living and without the proper training and tools doing such a repair can be dangerous to you but also others on the road. Unibody cars are designed to react in a certain order. You alter that design you can put your life at risk...Eric