Standard

ACR 123 - Unibody Straightening Systems and Techniques

Course Description

Introduces unibody straightening systems and techniques used in automotive collision repair. Topics include: equipment types and usage, safety procedures, primary/rough and secondary damage pull, single pull correction, multiple pull correction, and impact or pull stress relief.

Competency Areas		Hours
Equipment Types and Usage		Class	1
Safety Procedures		D. Lab	2
Primary/Rough and Secondary Damage Pull		P. Lab/O.B.I.	7
Single Pull Correction		Credit	4
Multiple Pull Correction
Impact or Pull Stress Relief
Prerequisite:	ACR 122, ACR 127
Corequisite:

Course Guide

Competency	After completing this section, the student will:	Hours
		Class	D.Lab	P.Lab/ O.B.I.
EQUIPMENT TYPES AND USAGE		1	4	5
Tram gauge and center line	Explain and measure a unibody using tram gauge and center line gauge.
Universal	Explain and measure a unibody with a universal measurement system.
Laser	Describe a laser measuring system.
Dedicated	Describe a dedicated measuring system.
	Demonstrate the ability to use pull tanners correctly.
SAFETY PROCEDURES		1	0	9
Procedures	Follow and observe all alignment safety considerations.
PRIMARY/ROUGH AND SECONDARY DAMAGE PULL		2	4	14
Correction sequence	Explain the pulling sequence of "Last In First Out" in relation to primary corrective pulls to secondary corrective pulls.
	Demonstrate the ability to correct primary and secondary damage.
SINGLE PULL CORRECTION		2	4	14
Sequence and direction	Demonstrate the ability to correct primary and secondary damage with a series of single-direction pulls after developing a pulling sequence.
MULTIPLE PULL CORRECTION		2	4	14
Sequence and direction	Demonstrate the ability to correct primary and secondary damage with a series of multiple pulls after developing a pulling sequence.
IMPACT OR PULL STRESS RELIEF		2	4	14
Damage identification	Identify stress/deformation on unibody vehicles.
Stress relief procedures	Define stress in the auto collision repair industry.
	Explain how stress can be caused in unibody vehicles.
	Demonstrate the ability to relieve stress in a unibody structure.

Suggested Resources

Books

Chudy, H. T. (1988). The complete guide to automotive refinishing (2nd ed.). Englewood Cliffs, NJ: Prentice Hall.

Deroche, A. G. (1988). Automotive collision estimating and repair. Englewood Cliffs, NJ: Prentice Hall.

Deroche, A. G. (1988). Automotive refinishing handbook. Englewood Cliffs, NJ: Prentice Hall.

Duenk, L. G., et al. (1984). Auto body repair. Encino, CA: Bennett & McKnight.

I-CAR. (1984). Unibody auto collision repair (Series 1-9). Des Plaines, IL: Author.

Scharff, R. (1988). Motor auto body repair. Albany, NY: Delmar.