Level 3 Apprenticeship Inertia Definition Definition An object

Level 3 Apprenticeship

Inertia • Definition: Definition An object at rest tends to remain at rest, and an object in motion tends to continue in motion in a straight line unless acted upon by an outside force. .

Inertia Continued • For example, passengers in an accelerating automobile feel the force of the seat against their backs overcoming their inertia so as to increase their velocity. As the car decelerates, the passengers tend to continue in motion and lurch forward. If the car turns a corner, then a package on the car seat will slide across the seat as the inertia of the package causes it to continue moving in a straight line

External force is holding Internal forces keep moving

Rear Collision Forces within the vehicle resist movement External forces continue to move

Simple Collision Structure Collapses Uniformly

Simple Collision Pull Hold

Strength and design of Body structure will dictate the deflection of collision forces acting upon it

Deflection • a change of course after hitting somebody or something, or a changing of an objects course by being hit by it

Deflection of Forces

Frame Design

Deflection From Direction of Travel Offset frontal

Deflection From Direction of Travel Side impact

Another Example

Three Section Principle Front Centre Rear

Frontal Collision Forces

Frontal Impact

Stage 1 1

Stage 2

Stage 3

Stage 4 4

Forces in a Rear Collision

Stage 1

Stage 2

Stage 3

Stage 4

Side Impact

Forces Present in a Rollover

Typical Rollover

Measurement Reference Sources

CENTRE LINE • IS AN IMAGINARY LINE THAT RUNS LENGTHWISE THROUGH THE VEHICLE AND IS A REFERENCE FOR DETERMINING LATERAL ALIGNMENT AND MEASUREMENT Centre Plane Centre Line CL LATERAL MEASURMENT

CENTERLINE IS USED TO REFERENCE WIDTH THROUGHOUT THE VEHICLE. COMPONENTS MAY BE POSITIONED EQUALLY OFF OF CENTRE (SYMMETRICAL ) OR UNEQUALLY OFF OF CENTRE (ASYMETRICAL)

DATUM • IS AN IMAGINARY LINE WHICH IS USED TO ESTABLISH THE HEIGHT OF THE VEHICLES COMPONENTS AND IS A REFERENCE FOR DETERMINING VERTICAL MISALIGNMENT DATUM PLANE

DATUM PLANE • The reference line for all vertical body dimensions

ZERO PLANES FRONT CENTRE REAR

From the ‘Zero’ Plane we can establish length measurement 0 0

From the ‘Centre’ Plane we can establish width

The ‘Datum’ Plane establishes Height dimensions L W H With these dimensions we can reference all known control points

Measuring Tools

Datum Length Vs. Point to Point

TYPES OF MEASURING SYSTEMS 1. UNIVERSAL -Mechanical -Laser -Sonic 2. DEDICATED BENCH AND FIXTURE MEASURING -Mechanical -Laser

SELF CENTERING GAUGE

Strut Tower Gauge

Cross member Pin

Digital Tram Gauge

Tram Gauge Most Mitchell, Chief, & Hein-Werner specifications can be measured using a tram gauge set at equal lengths. Measurements can be read directly from the tram gauge bar scale or by measuring the distance from pointer to pointer

Tape Measure

Terms • perpendicular 1. at right angles: at right angles to a line or plane 2. vertical: perfectly vertical

Laser Systems - Single target - Mirrored / Beam splitter / 3 d - Multi laser 3 d - Reflective pulse laser Basic theory behind Genesis style systems

Multi Target Laser

Universal System

Fixed Universal system

Universal Bench

Dedicated Bench

Laser Measuring

Dataliner Laser measuring system

Dedicated Bench and Fixture System

Measuring Systems on the Internet • • • http: //www. car-o-liner. se/us/ http: //www. dataliner. se/ http: //www. hein-werner. com/ http: //www. chiefautomotive. com/ http: //www. lasermateusa. com/ http: //www. celette. com/

CRITICAL MEASUREMENT REFERS TO ANY DISTANCE FROM ONE POINT TO ANOTHER THAT MUST BE MEASURED ACCURATELY TO DIAGNOSE STRUCTURAL DAMAGE THESE AREAS INCLUDE: • TORQUE BOX WIDTH AND LENGTH • FRAME HORN WIDTH AND LENGTH • BALL JOINT POSITION • SRUT TOWER POSITION • SUSPENSION MOUNTING POINTS ETC. WHILE MOST MEASUREMENTS REQUIRE A DIMENSION SHEET, QUITE OFTEN CHECKING ONE SIDE TO ANOTHER WILL SUFFICE IF NO DIMENSION EXSISTS

BASIC STRUCTURAL ALIGNMENT

Body Centre Markings

Picture the Vehicle as a Box The Box is Divided Into 3 Sections

BY HANGING GAUGES ON THE UNEVEN BODY OF THE VEHICLE ALLOWS US TO LOOK AT THE UNDERBODY AS A FLAT LEVEL PLANE. THE GAUGES ALSO DIVIDE THE PLANE INTO THREE SECTIONS Front Centre Rear

THIS ALLOWS US TO VIEW THE GAUGES TO DETERMINE IF THE PLANE HAS BEEN DISTORTED BY THE COLLISION

EXAMPLES OF LATERAL AND VERTICAL MISALIGNMENT INCORRECT DATUM While level and datum both relate to vertical (up/down) alignment all three sections are still Level or parallel with each other

This structure is out of parallel (twist) this type of damage is not considered a datum misalignment as the front and rear sections are not up or down relative to the centre section TWIST

On the other hand, a vehicles front or rear section can be vertically misaligned (datum) and still remain parallel (level) to the centre section Incorrect datum

Datum and Level Misalignment

THREE STEPS FOR GAUGING: 1. DIVIDE THE VEHICLE INTO THREE SECTIONS 2. LOCATE ITS CONTROL POINTS 3. ESTABLISH A BASE FOR THE GAUGING PROCESS

CONTROL POINTS: • A POINT ON WHICH ANY STRUCTURAL ALIGNMENT IS DEPENDENT • POINTS UPON WHICH ALL MEASURING MUST BE TAKEN TO DETECT COLLISION DAMAGE BASIC CONTROL POINTS

MANUFACTURERS USE CONTROL POINTS FOR POSITIONING OF STRUCTURE DURING MANUFACTURE TECHNICIANS USE THEM AS GUIDES DURING THE REPAIR PROCESS COMMON REFERENCE AREAS: - HOLES - BOLTS - STUDS - SUSPENSION MOUNTING POINTS - RIVETS

ESTABLISHING A BASE 2 3 FIRST ESTABLISH THE CENTRE SECTION

BY INSTALL GAUGES AT THE EXTREME FRONT AND REAR OF THE STRUCTURE, WE DIVIDE THE VEHICLE INTO THREE BASIC SECTIONS FOR GAUGING PURPOSES • WITH THESE GAUGES INSTALLED, YOU CAN NOW COMPARE THE TWO BASE GAUGES TO EACH OTHER TO CHECK THE CONDITION OF THE CENTRE SECTION. • YOU CAN THEN SIGHT THE FRONT AND REAR SECTIONS FROM THE BASE SECTION TO DETERMINE COMPLETE AND OVERALL STRUCTURAL CONDITION

ADDITIONAL CONTROL POINTS - LOWER SUSPENSION IF IN THE AREA OF IMPACT - STRUT TOWERS IF UNITIZED - STEERING ATTACHMENT POINTS

CONTROL AREAS - MAY REQUIRE REMOVAL OF MECHANICAL COMPONENTS TO FACILITATE MOUNTING - MAY REQUIRE ADAPTERS TO FACILITATE MOUNTING

USING DATUM - WHAT IS THE PURPOSE OF DATUM IN TERMS OF COLLISION DAMAGE ANALYSIS AND REPAIR? - WHEN SHOULD DATUM BE USED? PURPOSE - PROPER SHEETMETAL ALIGNMENT - PROPER HEIGHT OF SUSPENSION MOUNTING AREAS USAGE. . . DIFFERENCES. SHEET METAL VS DIMENSION - ANYTIME THE BODY STRUCTURE HAS BEEN COMPROMISED AND STRUCTURAL COMPONENTS ARE INVOLVED

Setting Datum • Datum – 1. point of reference: a point, line, or surface used as a basis for measurement or calculation in mapping, surveying or measuring – Datum is used for all vertical alignment measurements – Used to restore and check correct positioning of both sheet metal and major control points

Areas of given Measurement reference

Measurement Reference Points to Observe

Setting Datum Control Points

Datum Length Vs. Point to Point

WHEN READING GAUGES, USE THE CENTRE SECTION AS YOUR BASE REFERENCE POINT TAKE NOTE OF LOADED AND UNLOADED SPECIFICATIONS!

OPTIONAL MOUNTING PRACTICES The location of the correct datum will be shown in the dimension manual

OVERCOMING OBSTACLES BY REVISING DATUM

Datum Revision Sheet

DAMAGE RELATING TO CENTRELINE SWAY: LATERAL MISALIGNMENT OF THE VEHICLE CENTRELINE (FRONT OR REAR)

DAMAGE RELATING TO LEVEL • THE TERM “LEVEL” REFERS TO ALL AREAS OF THE VEHICLE BEING PARALLEL TO ONE ANOTHER • HAS NOTHING TO DO WITH THE WAY THE VEHICLE SITS • CAN REFER TO THE FRONT, CENTRE OR REAR SECTIONS BEING OUT OF ALIGNMENT

• SLANG TERMINOLOGY FOR THIS CONDITION WOULD BE “DOWN AT THE COWL” WHEN IN FACT THE VEHICLES LEFT FRONT RAIL IS ACTUALLY “UP”. • AS THE VEHICLE RESTS ON ITS SUSPENSION, IT WILL APPEAR TO SAG AT THE LEFT COWL AREA HIGH OR LOW RAIL IS THE CORRECT TERM VERTICAL MISALIGNMENT

• THIS TERMINOLOGY LEADS YOU TO BELIEVE THAT THE VEHICLE NEEDS JACKING AT THE LEFT FRONT TORQUE BOX • WHAT IS REQUIRED IS BLOCKING AT THIS AREA, AND A DOWN PULL ON THE LEFT FRONT RAIL

THE EXCEPTION TO THE RULE IS “ TWIST ”. - TWIST REFERS TO AN OUT OF LEVEL CONDITION IN THE CENTRE SECTION - TWIST WILL HAVE (2) HIGH AND (2) LOW AREAS PRESENT TWIST - THE HIGH AND LOW AREAS WILL BE DIAGONAL OF EACH OTHER

Level LEVEL ONLY REFERS TO PARALLEL WITHIN THE VEHICLES STRUCTURE, AND HAS NOTHING AT ALL TO DO WITH HOW THE VEHICLE SITS IN RELATION TO THE FRAME MACHINE OR THE FLOOR

TWIST PERSPECTIVE VIEW AND TOP VIEW

DAMAGE RELATING TO DATUM INCORRECT DATUM ONLY

DIFFERENCES

DIAMOND - THIS CONDITION ARISES WHEN ONE FRAME RAIL IS MISLOCATED FORWARD OR REARWARD OF THE OTHER DIAMOND - THIS CONDITION IS APPARENT WHEN MEASURING THE CENTER SECTION DIAGONALLY (“ X ”) - NOT GENERALLY DIAGNOSED BY SELF CENTERING GAUGES

COLLAPSED RAIL - RAIL LENGTH IS COMPROMISED - DETECTED BY LENGTH MEASUREMENT USING A TRAM BAR CHECK LENGTH, WIDTH AND CROSS MEASURMENTS

COLLAPSED CROSSMEMBER WIDTH MEASURMENT

STRUT TOWER AND LOWER BALL JOINT WIDTH AFFECTS CAMBER AND SAI

BALL JOINT LENGTH AFFECTS CASTER

STRUT TOWER AND LOWER BALL JOINT LENGTH AFFECTS CASTER

READING SELF CENTERING GAUGES THESE GAUGES SHOW CORRECT FRAME OR BODY ALIGNMENT

Out of Level

Sag

Sidesway

Sequencing for Diagnosis • • • Twist (centre section only) Diamond (affects centreline front and rear) Level (parallel readings front and rear) Mash (length) Sidesway (centreline) Measurements (taken constantly)

Perfect Alignment

Sway

Out of L evel

Diamond?

POSITION YOURSELF CORRECTLY TO VIEW THE GAUGES Correct Incorrect

POSITIONING CORRECT DISTANCE 6’-10’ AWAY

TOO CLOSE

- THE TECHNICIAN MUST ALWAYS POSITION HIM OR HERSELF IN A CENTRAL LOCATION AS WELL AS BEING THE CORRECT DISTANCE AWAY CORRECT WHEN GAUGING FOR PARALLEL (LEVEL), YOU MUST SIGHT THE GAUGES WITH BOTH EYES OPEN

ALWAYS USE THE CENTRE (BASE) GAUGES AS YOUR REFERENCE POINT IN DETECTING ANY MISALIGNMENT WHEN GAUGING FOR CENTRELINE (LATERAL MISALIGNMENT) SIGHT WITH ONE EYE ONLY

SOMETIMES SIGHTING FROM THE OPPOSITE END AIDS THE TECHNICIAN WITH A CLEARER VIEW

VIEWING FROM THE OPPOSITE END OF THE VEHICLE

CHECKING THE CENTRE SECTION IF NO DIMENSIONS ARE AVAILABLE FOR DIAGONAL MEASUREMENT, THE FOLLOWING WILL APPLY: - IN THE CENTRE SECTION, CHECK THE LENGTH AND WIDTH OF REFERENCE POINTS AVAILABLE - ONCE VERIFIED EQUAL, SIDE TO SIDE AND END TO END, A CROSS MEASUREMENT CAN BE ACCOMPLISHED

THIS IS AN EXAMPLE OF INCORRECT WIDTH THAT WOULD CAUSE A PROBLEM WITH A “X” MEASUREMENT

IT IS POSSIBLE TO USE A STEEL MEASURING TAPE TO ACCOMPLISH A CROSS MEASUREMENT, PROVIDING THERE ARE NO OBSTRUCTIONS WHATSOEVER USE A TRAM BAR WHENEVER POSSIBLE

ON PICKUP TRUCKS THE CENTRE SECTION IS RELATIVELY SMALL CORRECT PROCEDURE EXTRA PRECAUTIONS SHOULD BE MADE SO AS NOT TO MEASURE OUTSIDE OF THE CENTRE SECTION OR INACCURATE READINGS WILL OCCUR

DIAMOND FRAME INCORRECT MEASURING DO NOT USE CAB MOUNTS AS A REFERENCE POINT

CENTRELINE MISALIGNMENT RESULTING FROM DIAMOND TYPICAL

NON-TYPICAL DIAMOND AND SWAY THIS SITUATION IS PRECISELY WHY WE CHECK FOR DIAMOND FIRST

- ONCE CHECK FOR DIAMOND IS COMPLETE, INSTALL THE TWO BASE GAUGES, #2 & #3. - COMPARE THEM FOR PARELLEL TO DETERMINE IF A TWIST CONDITION EXISTS CORRECT ALIGNMENT - IF THE GAUGES ARE NOT PARALLEL, A TWIST EXISTS

- ALTHOUGH TWIST CAN ONLY EXIST IN THE CENTER SECTION, THE TECHNICIAN CAN ASSUME IT WILL AFFECT THE LEVEL CONDITION OF THE END SECTIONS TWISTED STRUCTURE

REMEMBER, TWIST ONLY EXISTS IN THE CENTRE SECTION, ERRORS IN DIAGNOSIS WILL OCCUR IF THIS THOUGHT PLAN IS NOT FOLLOWED!

DETERMINING DAMAGE IN THE FRONT OR REAR SECTIONS Out of Level

PREDICTABLE AREAS OF DAMAGE

KEY AREAS OF GAUGE PLACEMENT DO NOT OMIT THIS GAUGE IF FRONTAL IMPACT IS SUSPECT

DO NOT OMIT CROSSMEMBER GAUGE!

READ # 1 B GAUGE TO THE #2 BASE GAUGE, Correct method of reading the main cross member to the base gauge This is the correct method

THEN READ THE 1 A GAUGE TO THE 1 B GAUGE THIS IS THE CORRECT PROCEDURE

TRUE SWAY: NO OTHER DAMAGE AFFECTS CENTRELINE NOTICE THE FRONT SECTION IS OUT OF SQUARE AND DAMAGE CAN ONLY BE CORRECTED BY PULLING LATERALLY

DIAMOND CONDITION WILL AFFECT CENTRELINE ON BOTH ENDS OF THE VEHICLE, HOWEVER THIS IS NOT A SWAY CONDITION SINCE PULLING THE DIAMOND- WILL CORRECT CENTRELINE. NO CORRECTION FOR SWAY WILL BE NECESSARY

RAIL LENGTH / SHORT RAIL • AS ONE SIDE IS SHORTENED BY THE FORCE OF THE COLLISION, IT DISTORTS THE CENTRELINE READING TOWARD THAT SIDE OF THE VEHICLE. • AGAIN, THIS IS NOT A TRUE SWAY SINCE PULLING STRAIGHT FORWARD TO RESTORE THE RAIL LENGTH WILL CORRECT THE CENTRELINE

OTHER ISSUES THAT CAN CAUSE CENTRELINE MISALIGNMENT

SHORT RAIL, CENTRELINE CORRECTION PROCEDURE

Correct Datum Note Gauge Position

NOTE GAUGE POSITION ON FIRST GAUGE Incorrect datum

SUSPENSION / CROSSMEMBER / CRADLE MUST BE GAUGED AND BE LEVEL WITH THE BASE OF THE VEHICLE

ANOTHER CRITICAL AREA TO BE GAUGED IS AT THE LOWER CONTROL ARM MOUNTING POINTS

MANY NEW VEHICLES HAVE A SUB-FRAME ASSEMBLY THAT CAN SUSTAIN DAMAGE OR MOVEMENT DURING A FRONTAL IMPACT THIS REQUIRES GAUGING AND MEASURING PROCEDURES BE PERFORMED TO ENSURE CORRECT ALIGNMENT OF THESE MEMBERS TO THE UNIBODY STRUCTURE

IF A VEHICLE UTILIZES STRUT TYPE SUSPENSION, GAUGING OF THE STRUT TOWERS IS NECESSARY CENTRELINE AND LEVEL ARE CRITICAL

CENTRELINE AND LEVEL ARE VERY IMPORTANT

THE CROSSMEMBER PIN, ONCE INSTALLED, WILL ACT AS A GUIDE FOR COMPARING CENTRELINE TO THE SELF CENTERING GAUGES

IT IS IMPORTANT FOR THE SUSPENSION MOUNTING POINTS TO BE IN THE RIGHT LOCATION IN REGARDS TO DATUM

WIDTH AT THE SUSPENSION MOUNTING POINTS IS ANOTHER IMPORTANT AREA OF MEASURMENT THIS CAN BE A DIFFICULT AREA TO DIAGNOSE, AND A TRAM GAUGE WITH LONG POINTERS MAY BE THE RIGHT TOOL

USING THE STRUT TOWER GAUGE AS A TOOL FOR MEASURING LOWER BALL JOINTS ON A STRUT TYPE SUSPENSION. USING THE CENTER PIN, MEASURE LEFT AND RIGHT BALL JOINT LOCATIONS OFF OF THE PIN, THIS WILL HELP ESTABLISH SAI (STEERING AXIS INCLINATION) BETWEEN THE UPPER AND LOWER STEERING AXIS POINTS

MEASURING LOWER BALL JOINT LOCATION SHOULD ALWAYS BE PERFORMED IN ANY FRONTAL COLLISION. FULL FRAME ONCE CHECKED FOR LENGTH, CROSS MEASURE.

THE SAME PROCEDURE GOES FOR SUB FRAME MOUNTED SUSPENSION, CHECK LOCATION OF BALL JOINTS, LENGTH AND CROSS.

SEVERE IMPACT TO ONE SIDE OF THE VEHICLE CAN RESULT IN A TWISTED CROSSMEMBER AGAIN, THIS IS WHY INSTALLATION OF GAUGES IN THE CROSS MEMBER AREA IS IMPORTANT TO A PROPER REPAIR PROCEDURE

PROPER INSTALLATION OF GAUGES TO DETECT CROSSMEMBER DAMAGE

EFFECTS OF

REAR IMPACT HAS CAUSED DATUM MISALIGNMENT • REAR SECTION IS BELOW DATUM HEIGHT AND THE WHEELHOUSE ARCH IS ABOVE

INERTIAL FORCES DEFLECTION THROUGHOUT VEHICLE, RESULTING IN DIRECT AND INDIRECT DAMAGE

RESULTING DAMAGE IS EVIDENT AFTER THOROUGH GAUGING IN THIS CASE, THE REAR IMPACT IS TYPICAL WHILE THE FRONT SECTION SUSTAINED VERTICAL DEFLECTION RESULTING IN DATUM MISALIGNMENT

TYPICAL DEFLECTION IN A REAR COLLISION

TYPICAL CROSS MEASURING AREAS WHEN CHECKING UPPER BODY DIMENSIONS CAN COME FROM SOURCES SUCH AS REPAIR MANUALS, OR BE REFERENCED FROM KNOWN STRUCTURAL AREAS OF THE VEHICLE SUCH AS SEAT BELT MOUNTING POINTS ETC.

Upper Body Dimension Chart

STRUT TOWER MOUNTING GAUGE CAN BE USEFUL IN MANY LOCATIONS OF THE VEHICLE

EXAMPLE OF DAMAGE ANALYSIS SHEET

Measurement Tracking • Benefits – Completely assess damage – Ability to monitor progress – Determine pulling direction – Results in a more accurate repair