Wire size and Wire slot size(Length,width and depth), the wire slot should have enough space for the wire to stay inside.

For an example: Wire size 17AWG (1.15 mm), Slot: blade width 1.143, length=7.14 mm, depth= 5.95 mm

and we think if the depth is bigger, the wire can acquire more space to stay inside slot, while depth is more, length is more too,

Could you please check if the commutator was pressed consistanctly each time at same location according armature stack? The push pin witness marks on the commutator are consistent.

Because armature commutator and stack position is very important for indexing consistantly

Fully automatic winding machine with Japan as the pioneer, the rising demand for high quality products and low labor cost, operator only need to ensure enough raw materials, and replace them in time without workpiece or copper wire, so that continuous production can be ensured. The number of shaft is usually high, so as to achieve high efficiency production. A machine with enough automation can meet the requirements of an employee handle two or three winding machines at the same time.

Machine tooling composition, refer to following photo.