TM 9-4910-679-14&P
VALVE REFACER
The
Valve Refacer will produce accurate valve faces on valves up to 4"
diam. Its two universal motors independently operate the work spindle and the
grinding wheels. The grinding wheel spindle is double ended and extended so as
to permit the use of the Micrometer Valve Stem and Rocker Arm Grinding
Attachment on the right hand end of the Valve Refacer without disturbing the
refacing set-up. The 282, 550 and 626 machines are equipped with a 9/32"-9/16"
diameter valve stem collet. A 9/16"-3/4" and 7/32"-7/16" diameter valve stem
collet may also be ordered. For production grinding, an Air Chuck #37886 is
available for extra equipment.
UNPACKING & ASSEMBLY-Carefully follow instructions packed with
each Refacer. It is important that you follow each step closely, since this unit is a
Precision grinding machine. The Valve Refacer should not be lifted or moved by
holding onto the tables. Neither mount Refacer on a workbench where another
machine may be mounted nor place it where yibration is apparent, unless
mounted on shock-proof mountings.
VALVE REFACING OPERATIONS
CAUTION: Always wear eye protection.
TO CLEAN CARBON from VALVES-Mount a wire wheel brush on a Bench Grinder, and hold each valve firmly against
this spinning brush. Clean all surfaces of valve head face and stem and be sure that the carbon is completely removed
and not merely burnished. Polish valve stems with steel wool or crocus-cloth to remove any scratch marks left by the wire
brush. Any carbon remaining on the stem will affect accurate alinement in the Valve Refacer collet.
NOTE: Place valves in a numbered rack, or otherwise mark them, to keep them in proper order. Be sure to return
each valve to its own guide.
DRESSING the REFACING WHEEL-Included with every Valve Refacer as standard equipment is a wheel dressing
attachment with a diamond nib.
Place diamond dresser in collet and stabilizer in hole at front of housing under
spindle. Lock dresser in place with air chuck or hand wheel. Set workhead at 45.
Move the work table to where the diamond point is opposite the center of the face
of the grinding wheel. Switch on the Wheelhead Motor, turn on the coolant, and move the
center of the wheel face slowly and carefully into the diamond. Take light cuts-traverse
the diamond slowly across the full face of the grinding wheel. Any forward motion of the
grinding wheel for a new cut should be made with the diamond opposite the center of the
wheel face. This will prevent grinding the diamond out of its steel nib-as would happen if
the nib were moved against the edge of a wheel that had been advanced too far.
Light cuts keep the diamond cool for longer wear and better cutting, and give a smoother and more accurately dressed
wheel. As diamond wears turn the nib in holder 90 for uniform wear to obtain maximum service. Do not wear a diamond
down to its steel nib. One wheel dressing is usually sufficient for a set of valves.
To test for clean, accurate dress, hold thumb lightly across running wheel. If dressed properly, the wheel will feel
extremely smooth across its full face.
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