Porter-Cable PCB420SA, Instruction Manual

16

MAINTENANCE

• 

    For your safety, turn switch OFF and remove 

the power cord from the electrical outlet before 

adjusting or performing maintenance on your 

sander.

• 

    To avoid electric shock or fi re, all repairs to 

the electrical components should be done by 

a qualifi ed service technician. Before each use 

check for damaged, missing, or worn parts; 

check for alignment of moving parts, binding, 

improper mounting, or any other conditions 

that may affect the operation. Should any of 

these conditions exist,  do not use the sander 

until properly repaired or parts are replaced. 

Frequently blow or vacuum dust from all sander 

parts and motor housing.

REPLACING SANDING DISC (FIG. S, T)

To avoid injury, turn switch OFF and disconnect the 

plug from the power source before removing and 

installing sanding belt.

A sanding disc is pre-mounted at the factory. Use 

only sanding discs that measures 8 in. (203 mm) in 

diameter.

1.   Remove the disc worktable (See Fig. A on page 10), 

and then remove the disc cover (1) by removing six 
screws (2). 

2.   Remove the existing disc, and clean any residue left 

on disc plate (3). Only use mineral spirits to remove 
this residue. 

Fig. S

3.   Peel the plastic (4) back from new sanding disc (5) 

and carefully press sanding disc fi rmly in position 
around the sanding plate. Make sure the disc is 
centered on the plate.

4.   Reinstall the disc cover, tighten screws and place 

sanding table back on unit.

Fig. T

WARNING

!

ON

OFF

1

2

3

5

4

REPLACING SANDING BELT (FIG. U, V)

To avoid injury, turn switch OFF and disconnect the 
plug from the power source before removing and 
installing sanding belt.
Use only sanding belts that measures 4 in. 
(102 mm) in width / 36 in. (914 mm) in length.

1.  Remove the belt worktable. (See Fig. D on page 10)
2.  Position the belt work support frame horizontally 

as shown in Fig. U. Loosen the inner hex 
screw (1)  using a 5 mm hex wrench, turning it 
counterclockwise. Do not remove the screw. 

3.  Remove the two screws (2, 3) using a phillips head 

screwdriver, and pull out the tension lever (4) to 
release the tension of the sanding belt (5). Remove 
the belt exhaust cover (6). 

4.  Remove the sanding belt (5) from both sanding 

drums (7).

5.  Place new sanding belt over sanding drums. Make 

sure the belt arrow located on the inside of the belt is 
pointed in the right direction. 

6.  Replace the belt exhaust cover (6) in position. 
     

NOTE:

 Stretch the belt from the right side to make 

top and lower side of the belt fl at and tight as shown 
in Fig. V for keeping the belt exhaust cover (6) away 
from interferring with the sanding belt when placing 
the belt exhaust cover on. 

7.  Replace and tighten the two screws (2, 3) and push 

the tension lever (4) in to apply belt tension.

8.  Push the belt by hand and check if the sanding belt 

tends running to one side or the other of the two 
drums. 

9.  View from the switch end of sander, if the sanding 

belt runs toward disc, slightly turn the tracking knob 
(8) clockwise (down).

10. View from the switch end of sander, if the sanding 

belt runs away from the disc, slightly turn the 
tracking knob (8) counterclockwise (up).

11. Plug in the sander and turn the switch ON and OFF 

quickly to check if the sanding belt moves to either 
side. Re-adjust and fi ne-tune the tracking knob if 
necessary.

WARNING

!

WARNING

!