In the manufacture of transformers, what are the advantages and disadvantages of coil winding and manual winding?

　The advantage of the machine-wound transformer is that it has high efficiency and beautiful appearance. However, the toroidal transformer that winds a small hole is troublesome, and the reliability of the　insulation process is not as good as manual winding. Hand-wound In order to make the leakage magnetic flux of the transformer very small, it can be adjusted at any time in the winding process for the layout of the coil turns, so the real Hi-END transformer must be hand-wound, the only disadvantage of pure hand winding is Low efficiency and slow speed.