We have to say that we are impressed. Some of you are getting pretty sharp.
All of the suggestions made are valid and do come into play at varying degrees.
In essence what appears to be happening is that the slight resistance of the wire against the metal while burning at such a low feedrate simply make the machine run out of steam so to say. There's not enough velocity to counter the resistance. Voltage amounts sent to the amps are determined by gain settings which apply to a direct correlation between servo tuning and amp pot adjustments. So one solution is to get Galil's WSDK kit for tuning, If you haven't already done so.
In drymode there's no resistance.
In a perfect world you could afford gear reducers as already mentioned since servos do have the least torque at low rpm's. This is the opposite for steppers were there torque is best at low rpm's and drops significantly at higher cutting feedrate rates. Servos need a spinning action to maintain smooth motion. The higher the better. Applications such as Wire EDM that are highly accurate and slow burning need their servo's to maintain a higher rpm for the best cut quality.
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