(b) Enamel is to be cleaned from coil ex-
tensions. Cleaning is to start as near sleeving as
possible. Clean a 1/2-inch section of wire end pro-
jecting from a sleeving.
Maximum uncleaned wire
projecting from a sleeving section shall be 3 inches
minimum to 5 inches maximum. Wire diameter is
to be reduced a maximum of 5 percent. Cleaned
area shall have enamel removed over 80 percent of
(c) Slot tubes should be inserted with over-
hang equally divided on ends. Minimum slot tube
overhang (distance from core to end of slut tube)
shall be 1/4 inch. Position of the tubes should be
adjusted so that height of sides is equal. (fig. 9-3)
(d) After the slot tubes have been inserted,
insulating tape shall be placed into the stator to
form a bridge between slot tubes. It will be placed
so as to bridge every other tooth in the stator core
in one continuous length by stringing it through one
slot, crossing over at the end of the slot to the next
slot, back through and on to the third slot, continu-
ing until it is back at the starting point. The start-
ing and finish ends shall be securely tied together.
This bridge is to restrain the end turn tie cord.
(e) Coils shall be inserted in slots so that
overhanging ends are equally spaced. Wire bundles
at entrance to slot should be brought out as straight
and compactly as possible to reduce side pull on over-
hanging slot tube ends.
(f) Care should be taken to see that wire in-
sulation is not scratched or otherwise damaged. Coil
wires should not be kinked or crossed in the slots.
Tools inserted into slots to adjust position of wires
or separators should be free from burrs or sharp
edges to prevent damage to wire or slot insulation.
If it is necessary to use a mallet when tamping down
wires or separators in slots, tap the slot tools light-
ly. Heavy pounding will ruin the insulation.
(g) After bottom coil sides are in the slots,
the separators are wedged in place with their over-
hanging ends equally spaced. These ends should pro-
ject approximately 1-1/2 inches from edge of core.
The separators should fit tightly enough to hold the
coils down in the slots.
(h) Phase insulating strips are placed in the
end turns to insulate between the coil groups on both
ends of the winding.
These strips should be placed so
that the back edge reaches the ends of the wedges ap-
proximately 1/2 inch from core. The strips will then
overlap the ends of the separators. After coil ends
are properly shaped, trim phase insulating strips all
around so that 1/16 to 1/4 inch of edge projects be-
yond edge of wires.
Phase insulating strips may ex-
tend 1/2 inch beyond wire on coil outer diameters.
(i) Top sticks shall be carefully inserted so
that slot fibes and wire are not damaged. The over-
hanging ends should be equal and they should be level.
Top sticks which are broken or split during insertion
should be replaced.
(j) Connections shall be twisted together
and brazed using brazing alloy. The distance from
the first twist to the film coating on the wire must
not exceed 1-1/2 inches.
End of connection forming
pigtail shall be fusion welded as much as possible
with addition of alloy.
When coil pole leads and ends
consist of multiple wires, care must be taken to in-
sure that each wire is securely connected. All sharp
wire ends or spikes of solder remaining on brazed
joints should be trimmed off or flattened down to pre-
vent puncturing of insulation tape.
(k) When connectors are used instead of
brazing connections, wire must extend completely
through the connector.
The connector should be lo-
cated as close to the insulated portion of the wire as
is possible. Connectors must be applied using a
wire crimping tool -- crimping is not to be done us-
ing pliers, hammers or other make-shift arrange-
(1) Sleeving must be positioned to cover the
coil extension from the coil to which it is attached to
a point at least 1/2 inch under two layers of tape.
The sleeving at the coil end must be positioned to
provide a minimum of 3/8-inch creepage path from
the coil extension to adjacent coils.
(m) All connections in stator winding shall
be covered-with sleeving, MIL-I-3190/3. Where tape
is wide enough to cover the uninsulated wire and extend
a minimum of 1/2 inch over insulated portion of wire,
wrap one layer of tape over the connection, pressing
the two adhesive sides together for approximately
1/4 inch. The remaining length of tape should be
long enough to make two or more wraps over the con-
nection. The connection and any uninsulated part of
the wires adjacent to the connection will be covered
with three thicknesses of tape.
(n) Where the tape is not wide enough to
provide coverage for the connection, the tape shall
be wrapped around the connection such as to provide
l/2-inch lap plus 1/8 inch (minimum). The overlap
is to be such as to provide a minimum of two layers
of tape. The double layer of tape is to extend a min-
imum of 1/2 inch over the insulated portion of wire.
(o) Stator windings will be tied on lead end
Use a hitch or chain stitch tie. Spacing be-
tween ties is not to exceed 3 inches. A tie must be
made over each connection. Tie on either side of
cable bundle will be a double lace.
Tie must pass
through space between coils bridged by tape specified
under tie cord bracing ( (d) above).
(P) End turns on opposite lead side will not
be tied. However, the string ties, placed on the in-
dividual coils during coil winding operation, will be
left on untaped coil after insertion, to help keep
wires from being displaced.
(q) Refer to table 9-1 for winding data.
(2) Stator dip and bake (50/60 Hz).