3.Should the trowel arm inserts (bronze bushing ) (item 2 Fig.
34)come out with the trowel arm, remove the
4.Examine the
Checking Trowel Arm Straightness
Trowel arms can be damaged by rough handling, (such as dropping the trowel on the pad), or by striking exposed plumbing, forms, or rebar while in operation. A bent trowel arm will not allow the trowel to operate in a smooth fluid rotation. Ifbenttrowelarmsaresuspect, check for flatness as follows, refer to Figures 35 and 36:
31
4
2
5
6
10
7
8
9
1Spider Plate
2
3Hex Head Screw
4Hex Head Screw (Rounded)
5Hex Jam Nut
6Lock Washer
7Trowel Arm Lever
8Roll Pin
9Trowel Arm
10Arm Return Spring
Figure 34. Bronze Bushings
1Trowel Arm Round Shaft Section
2Trowel Arm Hexagonal (Hex) Shaft Section
3Lever Mounting Slot (Left Arm Shown)
4Roll Pin Hole
5Blade Attachment Bolt Hole (One of Three)
6Flat of Hexagonal Shaft (Top of Arm)
Figure 35. Trowel Arm
1.Use a thick steel plate, granite slab or any surface which is true and flat, to check all six sides of each trowel arm for flatness.
2.Check each of the six sides of the trowel arm (hex section). A feeler gauge of .004" (0.10 mm) should not pass between the flat of the trowel arm and the test surface along its length on the test surface. (Figure 36, Item 3) .
1Trowel Arm
2Flat Test Surface
3Feeler Gauge (.004 in. / 0.10 mm)
4Feeler Gauge (.005 in. / 0.127 mm))