S 122-009-N00
 (3)  Mechanical Blending (Power Blending)
 CAUTION:_______DO NOT PERMIT SPARKS TO TOUCH THE BLEND AREA. DO NOT OVERHEAT THE PART. BE SURE TO FREQUENTLY REMOVE ANY DUST REMAINING FROM THE BLENDING OPERATION.
 (a)  When blending, use a power tool (electric or air) with abrasive-impregnated wheels, stones, and/or pads.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 70-42-07
 ALL  ú ú N01 Page 203 ú Feb 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 (b)  
Blending can be done with more than one grade of abrasive (coarse to fine, as necessary) to remove damage and get the specified surface finish. Be sure to start with the least aggressive abrasive needed to remove the damage.

 (c)  
Use minimum pressure when you apply the blending tool to the part to prevent heat build-up. Do not permit abrasive wheels to become loaded up with any particles remaining from blending.

 (d)  
Mask surfaces that might receive sparks as a result of the blending operation.

 D. Buffing
 NOTE: Buffing is an optional operation that can be used to get the
____
 necessary surface finish while blending.

 S 122-010-N00
 (1)  Buff reworked area(s) with a power tool, a tampico (P05-058) brush, and burring polishing compound (P05-066) or silicon carbide deburring compound (P05-384).
 (a)  
Use minimum pressure when you apply the buffing brush to the part to prevent heat build-up.

 (b)  
Buff engine radial members in a radial direction.

 (c)  
Buff cylindrical surfaces in a circumferential direction.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 70-42-07
 ALL  ú ú N01 Page 204 ú Feb 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.