10
Figure 8‐2: belt tension adjustment
8.3.2 Tracking adjustment
A belt tracks correctly when it moves centrally on the
conveyor rollers without drifting to either side.
Tracking adjustments are made while conveyor belt is
running.
1.
Make sure proper belt tension has been
achieved (
sect. 8.3.1
).
2.
Turn on conveyor and set to maximum speed.
Watch for tendency of conveyor belt to drift to
one side of conveyor.
3.
If conveyor drifts, slightly loosen two screws (A,
Figure 8‐2) and turn take‐up screw (B, Figure 8‐
2) on
one side
of conveyor as needed.
Note:
Adjust take‐up screw only 1/4‐turn at a
time. Allow time for belt to react to adjustments
before proceeding further.
4.
When adjustment is satisfactory, tighten two
screws (A, Figure 8‐2).
Avoid over‐adjusting, as this may affect belt tension.
If tension is affected, if may become necessary to use
both take‐up screws to accomplish tensioning and
tracking.
8.4
Inspecting drum alignment
The sanding drum must be parallel to conveyor table
for proper machine operation. The sanding drum
comes pre‐aligned from the manufacturer. If a
problem with drum alignment should occur, follow
the instructions below.
First, inspect the alignment with a gauge of some
kind. The following procedure uses a steel straight‐
edge as a gauge.
1.
Unplug sander from power source.
2.
Open hood and remove abrasive strip from
drum.
3.
Position gauge (F, Figure 8‐3) between drum and
conveyor table at
outboard
side of drum.
Figure 8‐3: drum alignment
4.
With hood open, lower sanding drum while
slowly rotating drum by hand, until drum lightly
contacts gauge. NOTE: Make sure gauge is
contacted by the drum, not just the tension
rollers. Make a note of the measurement on the
sander’s depth scale.
5.
Remove gauge and place under drum at
inboard
side.
6.
If drum does not contact gauge equally on both
ends of drum, alignment is needed.
8.4.1 Performing drum alignment
To align conveyor table with drum:
1.
Loosen both table locking screws (C, Figure 8‐3)
with 5mm hex wrench.
Loosen both table locking
screws before adjusting drum alignment.
To e.g.
raise
outboard end of table, loosen lock
nut (E, Figure 8‐3) and rotate knurled nut (D,
Figure 8‐3) clockwise (+).
2.
Verify setting using the gauge. Make further
adjustments using knurled nut as needed.
3.
Retighten table lock screws (C).
8.4.2 Fine‐tuning drum alignment
Note: This is an operational test for sanding boards
wider than the drum. Perform this procedure only
after you have become familiar with sander
operation.
When sanding boards wider than the drum, table
alignment is critical and table must be adjusted
exactly level to slightly lower on the outboard end.
This will prevent any ridges from developing in the
stock. Always check this on a piece of scrap wood, as
follows, before sanding the work piece.
1.
Run a piece of scrap wood approximately
150mm wide by 400mm long through the sander
sideways so that end of board extends past
outboard side of drum, so that approximately
50% of the surface is machined.
2.
Without changing drum height, rotate board
180° and sand the same side.