Central Pneumatic 93742 User manual

6” Random Orbit
Palm Sander
ASSEMBLY AND OPERATING INSTRUCTIONS
3491 Mission Oaks Blvd., Camarillo, CA 93011
Visit our Web site at http://www.harborfreight.com
Copyright © 2005 by Harbor Freight Tools®. All rights reserved. No portion of this
manual or any artwork contained herein may be reproduced in any shape or form
without the express written consent of Harbor Freight Tools.
For technical questions and replacement parts, please call 1-800-444-3353.
93742
Due to continuing improvements, actual product may differ slightly from the product described herein.

SKU 93742 For technical questions, please call 1-800-444-3353. Page 2
Specications
Save This Manual
You will need the manual for the safety warnings and precautions, assembly
instructions, operating and maintenance procedures, parts list and diagram. Keep
your invoice with this manual. Write the invoice number on the inside of the front
cover. Keep the manual and invoice in a safe and dry place for future reference.
Safety Warnings and Precautions
WARNING: When using tool, basic safety precautions should always be
followed to reduce the risk of personal injury and damage to equipment.
Read all instructions before using this tool!
1. Keep work area clean. Cluttered areas invite injuries.
2. Observe work area conditions. Do not use machines or power tools such
as air compressor in damp or wet locations. Don’t expose to rain. Keep work
area well lit. Do not use electrically powered tools in the presence of ammable
gases or liquids.
3. Keep children away. Children must never be allowed in the work area. Do
not let them handle machines, tools, or air lines.
4. Store idle equipment. When not in use, tools must be stored in a dry location
to inhibit rust. Always lock up tools and keep out of reach of children.
5. Use the right tool for the job. Do not attempt to force a small tool or
attachment to do the work of a larger industrial tool. There are certain
applications for which this tool was designed. It will do the job better
and more safely at the rate for which it was intended. Do not modify this
tool and do not use this tool for a purpose for which it was not intended.
6. Dress properly while working. Do not wear loose clothing or jewelry as they
can be caught in moving parts. Protective, electrically nonconductive clothes
Construction Cast Aluminum Body, PVC Outer
Housing, and Brass Air Inlet Backing Pad 3/8” x 5-7/8” Polyurethane Disc
Air Inlet
Dimensions 1/4”-18 NPT Female Speed 10,000 RPM random orbital motion
Average Air
Consumption 7 CFM @ 90 PSI Max. Air Pressure 90 PSI
Overall
Dimensions 5-¾”L x 4-½”W x 4-½”H Net Weight 2 Lbs.

SKU 93742 For technical questions, please call 1-800-444-3353. Page 3
and nonskid footwear are recommended when working. Wear restrictive hair
covering to contain long hair.
7. Use eye and ear protection. Always wear ANSI approved impact safety
goggles. Wear a full face shield if you are producing metal lings or wood chips.
Wear an ANSI approved dust mask or respirator when working around metal,
wood, and chemical dusts and mists.
8. Do not overreach. Keep proper footing and balance at all times. Do not reach
over or across running machines.
9. Maintain tools with care. Keep tools clean and in good condition for better and
safer performance. Follow instructions for lubricating and changing accessories.
Inspect tool ttings and hoses periodically and, if damaged, have them repaired
by an authorized technician. The tool must be kept clean, dry, and free from oil
and grease at all times.
10. Disconnect Air Hose before maintenance. Never service the Sander, clear
jams, or disassemble with the air hose attached. Disconnect the Sander when
not in use.
11. Remove adjusting keys and wrenches. Check that keys and adjusting
wrenches are removed from the tool or machine work surface before connecting
it.
12. Avoid unintentional starting. Be sure the valve lever is in the Off position
when not in use and before attaching to pressure source.
13. Stay alert. Watch what you are doing, use common sense. Do not operate
any tool when you are tired.
14. Check for damaged parts. Before using any tool, any part that appears
damaged should be carefully checked to determine that it will operate properly
and perform its intended function. Check for alignment and binding of moving
parts; any broken parts or mounting xtures; and any other condition that may
affect proper operation. Any part that is damaged should be properly repaired
or replaced by a qualied technician. Do not use the tool if the trigger does not
operate properly.
15. Replacement parts and accessories. When servicing, use only identical
replacement parts. Use of any other parts will void the warranty. Only use
accessories intended for use with this tool. Approved accessories are available
from Harbor Freight Tools.
16. Compressed air only. Never use combustible gas as a power source.
17. Do not operate tool if under the inuence of alcohol or drugs. Read warning
labels on prescriptions to determine if your judgment or reexes are impaired
while taking drugs. If there is any doubt, do not operate the tool.

SKU 93742 For technical questions, please call 1-800-444-3353. Page 4
18. Use proper size and type air pressure line and ttings. The recommended
air line for this tool is 3/8” ID delivering no more than 90 PSI.
19. Maintenance. For your safety, service and maintenance should be performed
regularly by a qualied technician.
20. Disconnect air supply before adjusting Sander or replacing Sanding Pad.
Before making any adjustments to the Sander make sure that the compressed
air is disconnected.
21. Use Sander on an appropriate work surface only. Test sander on a test
scrap of material before sanding the workpiece. Always wear ANSI approved
safety goggles during use and maintenance.
22. WARNING: Some dust created by power sanding, sawing, grinding, drilling,
and other construction activities, contain chemicals known [to the State of
California] to cause cancer, birth defects or other reproductive harm. Some
examples of these chemicals are:
Lead from lead-based paints
Crystalline silica from bricks and cement or other masonry products
Arsenic and chromium from chemically treated lumber
The Brass components of this product contain lead, a chemical known to the
state of California to cause birth defects (or other reproductive harm).
(California Health & Safety Code § 25249.5, et seq.)
Warning: The warnings, cautions, and instructions discussed in this instruction
manual cannot cover all possible conditions and situations that may occur. It
must be understood by the operator that common sense and caution are factors
which cannot be built into this product, but must be supplied by the operator.
Unpacking
When unpacking, check to make sure the following parts are included.
Palm Random Orbital Sander
6” Backing Pad
22 mm Chrome Plated Flat Wrench
If any parts are missing or broken, please call Harbor Freight Tools at the number
on the cover of this manual.

SKU 93742 For technical questions, please call 1-800-444-3353. Page 5
Air Pressure Supply
This tool is designed to operate with a maximum air pressure of 90 PSI. You must
use an air regulator, set at 90 PSI or below.
In use, this tool will use, on average, 7 Cubic Feet per Minute of compressed air
at 90 PSI. For satisfactory performance, you must use an air compressor capable
of delivering this volume of air at the stated pressure.
We recommend that you use both a lter and an inline oiler in your air supply sys-
tem as illustrated in the diagram below. These components are not included with
this tool, but are available from Harbor Freight Tools.
If you do not use a lter and inline oiler, put a few drops of water displacement oil
into the air line before each use. After each use, the Palm Sander should be care-
fully drained of collected moisture and sprayed with a water displacement oil.
We recommend that you install a quick-release nipple (not included) into the
Regulator. Quick release connectors at all points in an air pressure system make
your work easier.
Air
Sander
Operation
Installing the Sanding Pad
1. Disconnect the air hose from the tool.
2. Select the appropriate sanding pad (not included), and press it onto the
Backing Pad (31). NOTE: You should always start with a sanding pad coarse
enough to remove saw marks and do preliminary shaping of the workpiece.
Then sand the workpiece with progressively ner grit sanding pads until the
desired surface is achieved. Do not move directly from a coarse grit sanding
pad to a much ner grit sanding pad. Doing so wastes time and causes
additional wear on you and the tool.

SKU 93742 For technical questions, please call 1-800-444-3353. Page 6
Removing Backing Pad (31)
1. Disconnect tool from air supply.
Slide Wrench (36) under Skirt (30)
as shown in photo at right. Engage
Wrench with Pad Retainer (38).
2. Holding Wrench rmly, rotate Backing
Pad (31) counterclockwise to remove.
Replacing Backing Pad (31)
3. Press sanding pad onto a piece of scrap material, and operate tool briey.
This will seat sanding pad rmly on Backing Pad (31). Failure to seat
sanding pad may cause sanding pad to come loose, possibly causing
personal injury or property damage.
Using the tool
CAUTION: Whenever using this tool wear ANSI approved safety goggles.
4. Turn the air compressor (not included) on and allow the air tank to come up
to pressure. Set the compressor output regulator to no more than 90 PSI.
5. Attach the air supply hose (not included) to the tool.
6. Grip the base of the tool in one hand. The Valve Lever (1) will be under
your palm. Squeeze the tool to depress the Valve Lever (1) and the tool will
operate.
7. Place the tool on the work surface to begin sanding.
8. To stop sanding, lift the tool from the work surface, and relax your grip to
allow the Valve Lever (1) to lift into the closed position.
9. When you are done work, disconnect the air pressure hose from the tool,
and turn off the air compressor.
Removing Sanding pad
1. Disconnect air pressure hose from tool.
2. Hold tool with sanding pad upward. Peel sanding pad from Backing Pad (31).
NOTE: Do not store tool with sanding pad in place. Heat generated during
sanding may cause pad to bond to Backing Pad, making subsequent
Wrench (36)
Skirt (30)
Backing Pad (31)

SKU 93742 For technical questions, please call 1-800-444-3353. Page 7
1. Disconnect air pressure hose from tool
2. Place Wrench (36) onto Pad Retainer (38) and hold rmly.
3. Place Backing Pad (31) on Pad Retainer (38) and turn clockwise to attach.
Hand tighten rmly.
Maintenance
PLEASE READ THE FOLLOWING CAREFULLY
THE MANUFACTURER AND/OR DISTRIBUTOR HAS PROVIDED THE PARTS DIAGRAM
IN THIS MANUAL AS A REFERENCE TOOL ONLY. NEITHER THE MANUFACTURER NOR
DISTRIBUTOR MAKES ANY REPRESENTATION OR WARRANTY OF ANY KIND TO THE
BUYER THAT HE OR SHE IS QUALIFIED TO MAKE ANY REPAIRS TO THE PRODUCT OR
THAT HE OR SHE IS QUALIFIED TO REPLACE ANY PARTS OF THE PRODUCT. IN FACT,
THE MANUFACTURER AND/OR DISTRIBUTOR EXPRESSLY STATES THAT ALL REPAIRS
AND PARTS REPLACEMENTS SHOULD BE UNDERTAKEN BY CERTIFIED AND LICENSED
TECHNICIANS AND NOT BY THE BUYER. THE BUYER ASSUMES ALL RISK AND LIABILITY
ARISING OUT OF HIS OR HER REPAIRS TO THE ORIGINAL PRODUCT OR REPLACEMENT
PARTS THERETO, OR ARISING OUT OF HIS OR HER INSTALLATION OF REPLACEMENT
PARTS THERETO.
1. Place a few drops of light weight air tool oil (not included) into the Regulator
each time before using the tool.
2. After each use, drain any accumulated moisture from the tool, and spray a
small amount of water displacing oil into and on the tool. Wipe clean.
3. Store tool in a safe location out of reach of children and unauthorized
persons.
Troubleshooting
Tool will not operate.
1. Possible cause: Low or no air pressure.
Solution: Check air compressor to be sure it is operating properly. Check Air
Regulator. Check air lines for leaking or blockage.
2. Possible cause: Corroded Rotor (39).
Solution: Spray light weight penetrating oil into the Regulator. If tool still
won’t operate, take it to a qualied service technician for repair.
3. Possible Cause: Damaged Seals or O rings.
Solution: Take it to a qualied service technician for repair.
NOTE: Some parts are listed and shown for illustration purposes only and are not available individually
as replacement parts.

SKU 93742 For technical questions, please call 1-800-444-3353. Page 8
Part Description QTY. Part Description QTY. Part Description QTY.
1VALVE LEVER 1 16 UPPER BEARING CASE 1 27 BASE RING 1
2SPRING PIN Ø3X25MM 1 17-1 CYLINDER 1 28 CAP SCREW (M4X12) 4
3BODY COVER 1 17-2 SPRING PIN Ø3X5MM 1 29 SCREW (M4X12) 1
4BODY 1 17-3 O-RING P7 1 30 SKIRT 1
5VALVE PIN SLEEVE 1 17-4 SPRING PIN Ø3X5MM 1 31 6” BACKING PAD 1
6WAVE WASHER 12MM 1 17-5 SPRING PIN Ø3X5MM 1 32 SILENCER SET 1
7O-RING P8 2 18 LOWER BEARING CASE 1 33 UPPER SIDE PLATE 1
8O-RING P4 X Ø7MM 1 19 BEARING (6000ZE) 1 34 LOWER SIDE PLATE 1
9VALVE 1 20 SHAFT W/HEAD (A) 1 35 SCREW (M5X10) 1
10 VALVE SPRING 1 21 H/R KEY (3X13) 1 36 FLAT WRENCH 1
11 PIN Ø3X22MM 1 22 BEARING (60012RS) 1 37 BALL BEARING (688ZE) 1
12 INLET 1 23 FELT RING (Ø18) 1 38 PAD RETAINER 1
13 SCREW M5X10 1 24 DUST SEAL 1 39 ROTOR 1
14 CONICAL WASHER M 1 25 SNAP RING (NR28) 1 40 VANE 5
15 (BEARING 6000ZE) 1 26 BODY GASKET 1
Parts List
Assembly Drawing

SKU 93742 For technical questions, please call 1-800-444-3353. Page 9
90 Day Warranty
Harbor Freight Tools Co. makes every effort to assure that its prod-
ucts meet high quality and durability standards, and warrants to
the original purchaser that this product is free from defects in ma-
terials and workmanship for the period of 90 days from the date
of purchase. This warranty does not apply to damage due directly
or indirectly, to misuse, abuse, negligence or accidents, repairs or
alterations outside our facilities, criminal activity, improper installa-
tion, normal wear and tear, or to lack of maintenance. We shall in
no event be liable for death, injuries to persons or property, or for
incidental, contingent, special or consequential damages arising
from the use of our product. Some states do not allow the exclusion
or limitation of incidental or consequential damages, so the above
limitation of exclusion may not apply to you. THIS WARRANTY IS
EXPRESSLY IN LIEU OF ALL OTHER WARRANTIES, EXPRESS
OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANT-
ABILITY AND FITNESS.
To take advantage of this warranty, the product or part must be re-
turned to us with transportation charges prepaid. Proof of purchase
date and an explanation of the complaint must accompany the mer-
chandise. If our inspection veries the defect, we will either repair
or replace the product at our election or we may elect to refund the
purchase price if we cannot readily and quickly provide you with a
replacement. We will return repaired products at our expense, but
if we determine there is no defect, or that the defect resulted from
causes not within the scope of our warranty, then you must bear the
cost of returning the product.
This warranty gives you specic legal rights and you may also have
other rights which vary from state to state.
3491 Mission Oaks Blvd. • PO Box 6009 • Camarillo, CA
93011 • [phone]