Trammel Gauge, Comparison & Direct Reading Check & Typical Pointers Application

FIGURE 9:

HOW TO USE THE TRAMMEL GAUGE

1. Place the vehicle on a 2 or 4 post hoist.

2. Insert the straight pointer with the stepped tip in one of the floor frame jigging holes (Fig. 9).
3. For the particular check in process, select the most suitable shape of pointer for the other end of the gauge.

FIGURE 10:

4. Keep the trammel gauge main tube as parallel to the vehicle frame as possible and use the shortest pointers possible for each check (Fig. 10).

FIGURE 11:

COMPARISON CHECK

The checking procedure is the same for both diagonal and length checks (Fig. 11).

1. Insert the straight pointer with the stepped tip in one of the floor frame jigging holes (A).

2. Now extend the trammel gauge so that the second pointer may be inserted in hole (B) to be checked.

3. Tighten the gauge wing nut when the gauge is the correct length.

4. Compare length AB with length A'B' on the opposite side of the frame. Do not disturb the pointers or the set length of the trammel gauge.

FIGURE 12:

CHECK BY DIRECT READING

1. Adjust the trammel gauge as described in the comparison check and align pointer (B) with the hole (Fig. 12).

FIGURE 13:

2. Mark a line (C) with a pencil on the sliding rule opposite the center mark on the vernier scale (Fig. 13).

3. Repeat this measurement on the other side of the frame and compare the length difference, which is 4 mm in this example (Fig. 13).

FIGURE 14:

TYPICAL POINTER APPLICATIONS

Refer to Figure 14 for application illustrations.