JOSAM laser AM
Measuring system
32
Measurement of rigid axles
Millimeter per meter
Toe-in/toe-out
Measuring of axle C3/C4.
Preparations are the same as the measurement of
rear axle C5/C6.
Calculation
Measure the distance between the measuring
scales A1 and B1. For example: D = 6m.
Wheel C3 left side
Aim laser dot at the measuring scale A1 left front.
Read the value.
For example: 89 Write down the result on the Test
Report Sheet, square A1.
Aim the laser dot at the measuring scale B1 left rear.
Read the value.
For example: 113 Record this on the Test Report
Sheet, square B1.
Rolling direction of wheel C3 is the difference
between the readings of measuring scales A1 and
B1. 89 - 113 = -24
Divide the difference -24 by the distance between
the measuring scales A1 and B1, D = 6m.
The result: -24 : 6 = -4 (mm/m).
Write down 4 at C3/Dm and circle a (-) sign.
Wheel C4 right side
Aim the laser dot at the measuring scale A2 right front.
Read the value.
For example: 108 Write down the result on the
Test Report Sheet, square A2.
Aim the laser dot at the measuring scale B2 right rear.
Read the value.
For example: 96 Write down the result in the Test
Report Sheet, square B2.
Rolling direction of wheel C4 is the difference
between the readings of measuring scales A2 and
B2. 108 – 96 = +12.
The result: +12 : 6= +2 (mm/m).
Write down 2 at C4/Dm and circle a (+) sign.
The result can be calculated by using the table to
the left.
Calculate toe-in/toe-out
C3/Dm = - 4
C4/Dm = +2
Result = - 2 (toe-out)
If the (-) value is greater, the result is toe-out.
If the (+) value is greater, the result is toe-in.
Draw rolling direction of the wheel with a solid line.
Draw the axle location with a solid line.
Total difference between front and rear measuring scales
Distance in meters between the measuring scales
