WTB: Encoder (or complete servo) for Hurco CNC

gr8legs

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Well, MillZilla (my Wells-Index mill with a Hurco KM-3P CNC retrofit) has thrown a shoe and lost her mind on the Z-Axis.

A bit of troubleshooting reveals a non-functioning encoder on the Z-Axis Stepper motor.

Apparently Hurco used several different motors/steppers for their CNC and I need to replace the encoder with something compatible. Servo motor are Reliance Electro-Craft Model E727, P/N 727-903-0862.

Photos show servo in installed position and close-ups of encoder P/N (Renco? 77678-038), and encoder internals.

Anybody got a spare unit or a wrecked out mill with an intact servo? I am definitely willing to pay a reasonable sum as without this widget my CNC is dead, dead, dead :)

Thanks in advance

Stu

HurcoEncoderServoZ_Axis.jpgHurcoEncoder_P_N.jpgHurcoEncoderServoLabel.jpgHurcoEncoderBoard.jpg

American Airlines wants to cut costs by "simplifying" maintenance". Passengers can help by watching for falling parts
 
Stu I wonder if that encoder could be repaired? How hard is it to remove from the machine? I'm only 1 state away
Those two ICs are cheap and readily available. If you can send it to me I may be able to revive it for only parts cost and maybe a couple bucks labor
You might be able to stuff it into a small priority box
-Mark
 
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If you can figure out what the line count is, any 4 channel quadrature encoder will work. I have not be able to find the specs for that particular part number.
 
Progress (?) Report:

As the OP on this thread I spent a good deal of time twiddling with the servo and diagnosing encoder operation and associated wiring.

I determined that the processor was receiving 'count' pulses but not once-per-turn 'index' pulses - so perhaps just a loose or corroded connection somewhere between the encoder and the CPU was the problem.

Repeatedly removing and replacing the inter-board connections - perhaps cleaning them up in the process - (a tried and true troubleshooting technique) eventually returned the encoder to operating condition.

Whether this is actually a 'fix' or just a mirage is yet to be seen but for now it is working again and I am back and running. Good thing too as I was halfway through milling 1.392" diameter holes through two pieces of 1.5" CRS.

Thanks to Mark and Jim for the advice and encouragement!

Stu
 
Great news! When you get a chance go back and clean the connectors more thoroughly, probably keep it going forever
Chips seldom just fail for no reason, connectors are always prime suspects
-Mark
 
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