TM 9-3405-215-14&P
CHAPTER 4
MAINTENANCE
LUBRICATION
The slide rod, upset force selector cam, and all miscellaneous pivot points should be lubricated every six months. The
interval between lubrication may be shortened or lengthened, depending upon how much dust and dirt are in the area. If
the slide rod sticks, then the rod should be cleaned and greased more often. The grinder motor will not normally require
lubrication for several years. Use ASTM Grade 215 Union 76 UNAX RX 215, or equivalent oil on all lubrication points
except the slide rod.
SLIDE ROD MAINTENANCE
The slide rod should be kept clean and greased. Rust or dirt may cause rod to stick and "burn out" the weld.
Check movable jaw for freedom of movement. If it binds, apply a drop of oil to slide rod and work it in by repeatedly
pressing the lever. If this does not free the jaw movement, remove slide rod and clean and grease it. Before removing
slide rod, clamp a piece of saw band securely between welder jaws to maintain correct spacing. Use UNION 76 UNOBA
EP2 grease, or equivalent on slide rod.
The slide rod stop screw should not bind slide rod. Turn screw in, then back off 3/4 turn.
WELDER JAWS MAINTENANCE
To secure consistent results, the welder jaws must be kept clean. During the welding cycle, excess metal in the form of
incandescent particles is blown out of the weld, causing a scale or flash to build up on the welder jaws. The welder will
not weld properly unless the jaws are wiped clean after every weld.
Misalignment of the weld is usually caused by worn or dirty jaws. However, if the welder jaws are clean and not worn and
the welds are out of line, then the jaws are not aligned properly. This misalignment can be determined by inspection of
the weld after the flash has been removed. After determining which jaw is not in alignment, the jaws can be adjusted as
desired. Jaw alignment instructions are given in a separate "Engineering Adjustment Summary". Replace lower jaw
inserts that are worn excessively.
CUT-OFF SWITCH AND WELD SWITCH CONTACT POINTS
If the cut-off and weld switch contact points are welded together, pitted, corroded. or covered by oxide, they must be
replaced. If the points are only dirty, clean them with a commercial point cleaner and clean, lintless cloth (such as linen
tape).
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