METAL BODY REPAIR - OD1653 - LESSON 1/TASK 1
X-CHECKING FRAME ALIGNMENT WITH TRAM.
(16) Misalignment of a door opening in a body is generally checked by the
fit of the door. However, it may also be checked by the tram as shown in
figure 19 (on the following page). Measurements are taken by marking off a
distance X along the center pillar from B to C and a distance Y along the
body sill from B to A. Set the tram with its ends on points A and C and
compare this length with similar points on the undamaged side of the vehicle
or on a similar vehicle.
Any misalignment of the door opening will be
indicated by the necessity of resetting the tram.
(17) If both sides of the vehicle are damaged, lay out a rectangle such
as A B C D which is shown in figure 19, in a correctly aligned door opening
of a similar vehicle. Then measure the distance X and Y and transpose these
measurements to the door opening of the damaged vehicle. If the diagonals A
C and B D are not equal, the door opening is out of alignment.
(18) After the door openings on both sides of the vehicle have been
checked, measure the front section in the same manner. In this measurement,
the same points, A and D as before, are used together with points F and E in
corresponding positions on the opposite door openings, to form the corners
of a rectangle (figure 20 on the next page).
The diagonals A E and D F
should be equal. If they are not, the misalignment must be corrected before
other checks are made on the body.