Powermatic WB-43, WB-37, WB-25 operating instructions Table Parallelism

If the ends of the workpiece are sniped, the front pressure bars are too low. The pressure should be enough to firmly hold the workpiece against the conveyor, but not so hard that the ends of the workpiece spring up after clearing the bar.

Also, if the ends of the bars are not exerting equal pressure, the workpiece will tend to move sideways on the conveyor during sanding.

To raise or lower each set of pressure bars:

1.Disconnect sander from power source.

2.The sanding belt should be installed, and the air valve turned ON.

3.Place a sanded panel with even thickness on the conveyor table and under the pressure bars. The panel should be long enough to contact both front and back sets of pressure bars.

4.Raise the table manually using the handwheel (Figure 16) until the panel contacts the pressure bars.

5.Make sure the pressure at the right and left side of pressure bars is even.

6.If adjustment is needed, release the lock nut (A, Figure 17) with a 14mm wrench.

7.Insert the adjusting tool (B, Figure 17) into a hole in the adjusting knob. Rotate the adjusting knob clockwise to raise that side of the pressure bar, counterclockwise to lower it.

8.When finished, re-tighten lock nut (A, Figure 17).

9.11Table Parallelism

Parallelism of the conveyor table to the contact roller has been factory-set and should not require further adjustment. However, as the machine receives extended use, this setting should be checked.

Inspect parallelism by one of two methods:

1.Use a sanded board of equal thickness. Pass the board several times through the machine at a sanding depth of approximately 1/64”, then measure the thickness of the board at different points along the edges with calipers. If excessive variation occurs, the table needs adjusting.

OR, remove the sanding belt and place a gauge of some kind at one side of the conveyor table and below the contact roller. Raise the table manually using the handwheel until the gauge just touches the contact roller. Repeat at the other side of the table and compare the gauge readings.

Figure 16

Figure 17

17