How many of you remember that mid 70s Chevy Nova you saw from the rear, "dog tracking" so badly that you could clearly see the front fender and maybe even the front bumper end? I remember that scenario vividly, indicating a poorly repaired unibody vehicle. How many times have you seen poorly fitting sheet metal panels and elongated bolt-holes when you've lifted the hood of a customer's car?

Sonar and laser measuring equipment are both connected to a computer and can print an overview of the vehicle before and after the repairs have been performed. This is a requirement of most DRP programs and should be your requirement as well.

The importance of measuring

A dedicated fixture bench provides a method of measuring specific control points like those found in many unibody vehicles.

I know these sound ridiculous, and they should, because no one in their right mind would allow any one to perform any of the described operations that way. Yet some of us think it is OK to pull a unibody close enough, and then use a sheet metal panel as a ruler and trial-fit it several times to get the right pull dimension.

Think about how dangerous it can be to put an improperly repaired vehicle on our roads. The dimensions of the structure, the position of the sheet metal and the bumper mounting, the strength of the welds and the tensile strength of the steel itself are all taken into consideration when designing a car to be safe. Not one of us in the repair industry has the capacity to re-engineer these vehicles and alter the way they perform when involved in an impact. Yet this is precisely what we do by not following protocol during the repair.

What we can, and must do, is repair it back to the standards set by the manufacturer. The only way to do so accurately is to measure.

Tools and methods

There are a variety of measuring tools available today to utilize when looking to accurately measure a vehicle during the repair process.

Dedicated fixture bench

On a dedicated fixture bench, the jigs or "fixtures" are not intended just to rigidly mount and hold the vehicle during the pulling process. They also provide a method of measuring specific control points as well. Since many unibody vehicles are built this way, it is an extremely accurate method of measuring and repairing damaged structures.

Some of the older fixture benches were limited in their measuring capacity, allowing for measurements only on the underbody and strut towers. Calling this measuring may be misleading because when using a dedicated bench, typically the user is pulling the damaged vehicle to a reference point, or jigged point, rather than measuring a specific distance (the jig is set at the required point). I do not believe there is a system in use today as accurate as a dedicated bench.