Collision Repair: How to
Straighten
Auto Body Panels Using Our 6-Step Process
Don't worry if your straightening skills aren't the best, you can still do a satisfactory job. Deeper dents will simply require more pulling and layers of filler.
It's important to mention at this point that you can't apply a single thick layer of body filler in any one application. Filler is applied usually in 2-5 passes depending on the severity of the damage.
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Slightly damaged auto body panels can be straightened, pulled with a stud welder, a slide hammer and even pulled with a small frame machine. |
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Auto body panels damaged beyond your collision repair skills can be replaced or cut and replaced. |
Either way there is a solution open to you.
The tools you will need are...
The basic tools for doing bodywork include:
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An Air File, Like a Jig Saw to cut parts if needed. |
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A DA (Dual-Action) Sanderto get all of your body work done. |
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Small Grinder, Electric ones are the best I think. No need for air. |
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Dead Blow Hammer and or a set of Auto Body Hammers. Pretty affordable if you ask me... |
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Slide Hammer, or a Stud Welder. Now they have the Glue style pullers ..Pretty cool, but I still prefer the Stud Gun. |
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Sandpaper - A variety of grits. Not to worry, All of the steps here are on HD videos in the VIP Course. |
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A Pry Bar and some basic screwdrivers, maybe a screw gun if you're an auto nut like I am. |
The best way to learn how to use these tools is to simply pick them up and start using them, so don't be shy.
Experience will come with trial and error. Since the panel is already damaged, why not use it to practice on?
Straightening a Panel
Firstly, before you begin straightening a panel that was damaged during a collision, you must determine the original point of impact. There are two areas of damage to any panel involved in a collision:
1. The damage suffered from the actual impact.
2. The damage that occurs
from reaction forces.
Let me explain what I mean by reaction forces in simple terms using a straight forward example: Since a door is basically secured by its mounting points, an impact to the middle of the door would cause the panel to separate itself from its mounting points.
This is the reason why vehicle passengers who have been involved in a side impact, often have trouble opening the door to get out.
The Process of Straightening a Panel
The process of straightening a panel involves reversing the dent until the panel is as close to its original shape as possible. It is a combination of simply hammering the dent out from the opposite side, puling from the front and hitting the high spots down while pulling so that the dens does not go inverse.
You must work from the outer perimeter of the damaged area towards the point of impact. This can be a little tricky if there is more than one area of impact on the same panel but the process is still the same.
It is quite common for a dent in one portion of a panel to cause another area on the same panel to bulge outward. Start by hammering this outward bulged area back into the correct alignment before you start hammering the actual dented area back into place.
If you attempt to straighten the dent first it will cause the metal in the bulged area to stretch.
Working with Body Filler always means you don't need to be perfect!
Aim to straighten the panel to within 1/16-1/4 of an inch of its original form. You can then use a thin layer of body filler to cover up any remaining imperfections.
Unless you are able to metal finish the panel without using any filler, the repaired area needs to be left slightly lower than the undamaged area surrounding it.This is done to keep the body filler from building up above the surrounding area.
Never apply body filler at more than 1/8-1/4 inch thick at its deepest point. Doing so will result in the filler either sagging or cracking. Although this is very conservative and normal. I have seen MANY jobs come in with 1/2 - to entire corners of fenders filled with body filler. Sometimes the things you see are crazy!
I have seen socks, rags, and even newspaper stuffed in holes before the body filler was filled in. HAHA! I hope you don't do this to your personal jobs. Although you need to do what you need to do right? If the budget is tight and you have n choice but do to a "Quickie" thats what you do. But I like to also cover the importance of doing quality jobs.
I am a fanatic for NICE BODY WORK! Sometimes by being a perfectionist just makes the whole process take longer. But you'll get what you put into it right?
How To Straighten a Panel
The following is a 6-Step method to help you repair those dents in no time at all.
1. You will first need to pull out the dent in the sheet metal. This is made easier if you temporarily weld small metal rods to the damaged sheet metal using a Rospot or a stud gun. The rods should measure approx 1/8 inch in diameter and 2.5 inches long.
2. Using a slide hammer, slip it over the rods one at a time. You can then hammer out the dent using the slide to return the sheet metal back to its original position. You may need to tap the sheet metal back in a little if you accidentally hammer it out too far.
The slide hammer is then moved over to the next rod where it is again hammered out to undo the effects of the impact. It does take practice to read the dents and know exactly where to apply the right amount of pressure.
3. As you progress, check your work. You need to ensure every part of the panel is as close to its original shape as possible. You also don't want any portions of the panel to be too high.
Any high spots will need to be hammered back down into place and any low spots will need to be filled.
4. After all the pulling is done the rods can be cut off as close to the body as possible. You can accomplish this using a pair of diagonal cutters. The remaining stubs are easy to grind down using a coarse sanding disc and a grinder.
5. Next you will need to smooth the surface using body filler. After that add a light coat of glazing putty for the final surface.
A mixing board is needed for use when mixing filler or glaze. The filler would be mixed upon board and then applied, I like to use a piece of thick glass mounted on some plywood the same size as the glass. It maes for easy cleaning with a razor blade. You can also use a piece of card board. No problem.
Don't worry about any slight high spots; they can easily be guided back into place with the use of a small hammer, then filled again with your filler.
You will find that older vehicles have thicker sheet metal compared with newer modern day vehicles; which are a lot thinner and more flexible. Adjust the amount of effort you use to straighten the panel depending on the age of the vehicle.
6. Use a flexible spreader to carefully apply the filler to any low spots. Be careful to prevent air bubbles from forming. After the filler hardens it can then be sanded and shaped, starting with 80-grit sandpaper then to finer grits.
Tired of all of this reading? Get instant access to our famous Auto Body And Paint VIP Training Course used by special VIP members from all across the world!
Cheers!
-Tony



