9 10
*  Declared noise levels; measurements carried out in accordance with standard EN ISO 15744.
# Declared vibration levels in accordance with ISO 20643 and 28927.
IMPORTANT NOTE: The noise and vibration values stated in the table are from laboratory testing in conformity with stated codes and standards and are not 
sufcient risk evaluation for all exposure scenarios. The actual exposure values and amount of risk or harm experienced to an individual is unique to each 
situation and depends upon the surrounding environment, the way in which the individual works, the particular material being worked, work station design, as 
well as upon the exposure time and the physical condition of the user. 3M cannot be held responsible for the consequences of using declared values instead of 
actual exposure values for any individual risk assessment.
PRIOR TO THE OPERATION
The tool is intended to be operated as a hand held tool. It is always recommended that while using the tool, operators stand on a solid oor, in a secure position 
with a rm grip and footing. Be aware that the sander can develop a torque reaction. See the section in SAFETY PRECAUTIONS in.
Use a clean lubricated air supply that will give a measured air pressure at the tool of 6.2 bar (90 psig) when the tool is running with the lever fully depressed. It is 
recommended to use an approved 10 mm (3/8 in) x 8 m (25 ft) maximum length airline. Connect the tool to the air supply as shown in Figure 1. Do not connect the 
tool to the airline system without an easily accessible air shut off valve. It is strongly recommended that an air lter, regulator and lubricator (FRL) be used as shown 
in Figure 1 as this will supply clean, lubricated air at the correct pressure to the tool. In any case appropriate air pressure regulators shall be used at all times while 
operating this tool where the supply pressure exceeds the marked maximum of the tool. Details of such equipment can be obtained for your tool distributor. If such 
equipment is not used, the tool should be manually lubricated. To manually lubricate the tool, disconnect the airline and put 2 to 3 drops of suitable pneumatic motor 
lubricating oil such as 3M™ Air Tool Lubricant PN 20451 (or equivalent 10 centistoke oil) into the air inlet of the tool. Reconnect tool to the air supply and run tool 
slowly for a few seconds to allow air to circulate the oil. If the tool is used frequently, lubricate it on a daily basis or lubricate it if the tool starts to slow or lose power. 
It is recommended that the air pressure at the tool be 6.2 bar (90 psig) while the tool is running so the maximum RPM is not exceeded. The tool can be run at lower 
pressures but should never be run higher than 6.2 bar (90 psig). If run at lower pressure the performance of the tool is reduced.
Product Conguration / Specications
Operating / Maintenance Instructions
Model 
Number
Collet 
Maximum 
Rotational 
Speed 
(RPM)
Product Net 
Wt kg (lb)
Height mm 
(in)
Length mm 
(in)
*Noise Level 
dBA Pressure 
(Power)
#Vibration 
Level m/s
2
 
(ft/s
2
)
#Uncertainty 
K m/s
2
(ft/s
2
)
Series 
Designation
28330 
28345
1/4 in  
6 mm
18,000
0.58 (1.27) 
0.58 (1.27)
69.9 (2.75) 
69.9 (2.75)
178 (7) 
178 (7)
89.2 (100.8) 
89.2 (100.8)
2.13 (6.99) 
2.13 (6.99)
0.19 (0.62) 
0.19 (0.62)
C
28331 
28346
1/4 in  
6 mm
18,000
0.78 (1.72) 
0.78 (1.72)
69.9 (2.75) 
69.9 (2.75)
274 (10.8) 
274 (10.8)
82.9 (94.5) 
89.2 (100.8)
2.18 (7.15) 
2.18 (7.15)
0.24 (0.79) 
0.24 (0.79)
C
28332 
28347
1/4 in  
6 mm
4,000
0.90 (1.99) 
0.90 (1.99)
69.9 (2.75) 
69.9 (2.75)
221 (8.7) 
221 (8.7)
90.0 (101.6) 
89.2 (100.8)
1.43 (4.69) 
1.43 (4.69)
0.08 (0.26) 
0.08 (0.26)
C
20237 
25126
1/4 in 
6mm
20,000
0.96 (2.04) 
0.96 (2.04)
69.9 (2.75) 
69.9 (2.75)
190 (7.5) 
190 (7.5)
86.1 (97.7)
86.1 (97.7)
3.87 (12.7)
3.87 (12.7)
0.51 (1.7)
0.51 (1.7)
C
20238 
25127
1/4 in 
6mm
18,000
0.96 (2.04) 
0.96 (2.04)
69.9 (2.75)
69.9 (2.75)
190 (7.5)
190 (7.5)
89.7 (101.3)
89.7 (101.3)
3.8 (12.5)
3.8 (12.5)
0.43 (1.4)
0.43 (1.4)
C
20239 
25128
1/4 in  
6 mm
12,000
1.21 (2.67) 
1.21 (2.67)
1.44 (1.75) 
1.44 (1.75)
233 (9.19) 
233 (9.19)
82.1 (93.7) 
82.1 (93.7)
5.42 (17.78) 
5.42 (17.78)
0.47 (1.54) 
0.47 (1.54)
C
20240 
25129
1/4 in  
6 mm
8,000
1.16 (2.55) 
1.16 (2.55)
1.44 (1.75) 
1.44 (1.75)
226 (9.80) 
226 (9.80)
82.5 (94.1) 
82.5 (94.1)
2.96 (9.71) 
2.96 (9.71)
0.41 (1.35) 
0.41 (1.35)
C
28770 1/4 in  18,000 1.38 (3.05) 1.44 (1.75) 311 (12.25) 81.0 (92.6) 1.04 (3.41) 0.11 (0.36) C
Recommended Airline
Size - Minimum
10 mm               3/8 in
Recommended Maximum Hose Length
8 meters               25 feet
Air Pressure
Maximum Working Pressure  6.2 bar  90 psig
Recommended Minimum   N/A   N/A