PROCEDURE
BLAST WHEEL REPLACEMENT
When the blades on the blast wheel are deteriorated by 50% or more the blast wheel should be replaced.
To replace the blast wheel, perform the following steps:
• Verify control switch in the OFF position
• Verify power cord in NOT plugged into an electrical outlet
• Verify shot valve is closed
• Loosen nuts and clamps that secure feed spout and control cage
• Remove feed spout
• Remove control cage
• Mark plate with ink pen where control cage openings appear to aid in realignment
• Remove four sets of nuts and washers securing control cage assembly to housing
• Remove control cage assembly
• Remove arbor nut and blast wheel
• Check wheel hub for wear & replace as necessary
• Install new blast wheel and arbor nut
• Attach the control cage assembly previously removed
• Insert new control cage provided with blast wheel kit. Spin blast wheel by hand to verify blast wheel
and control cage do not come into contact. Openings of control cage should be set at approximately
10:30 and 8:30.
• Reattach feed spout
• Verify all nuts are tight and secure
• Briefly activate grinder motor to verify good balance & proper clearance
NOTE: Only blast wheels manufactured by National should be used in the #3390. Other blast
wheels have not been tested by National and could result in damage to the equipment or injury to
the operator.
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