The details about my CNC saga can be seen here but I doubt it's worth a complete read but it does set the stage and possibly make me look less stupid than the description below.
http://www.hobby-machinist.com/show...se-help-This-stopped-being-fun-a-few-days-ago
The mill I have has to go through a process when you first start it up to calibrate the axis. Part of that process involves running each axis (in order of Z, Y, X) to one of the limit switches. Z axis is fine and as it goes through the process I can see the value changing on the screen. When it goes to the next axis, Y, it moves but no values change on the screen and then I get a fault. Checked all the connections and everythings fine so that leads me to believe it the encoder. If you filter through the above thread you can see that my theories havn't worked out for the best with this thing. I would rather check parts before I start replacing them so that lead me to an oscilloscope.
That process of homing using a switch then rotating until an index is found is pretty much the standard all VMC's use going back decades..its how my Japanese CNC mill works and how a Fadal 3016 works.
I would definitely hold off on buying the oscilloscope until further notice. You can confirm encoder output in a gross sense by setting your multimeter to the Hz/Frequency measurement and measuring the encoder pulses at a known feedrate, and calculating what the frequency should be. I assume that encoder is a +5V with quadrature output and an index.
Or you could try swapping encoders between X and Y axis and see if the problem follows the encoder.
Does your mill use servomotors with encoder feedback to close the loop? If so, its unlikely there would be any control of the Y axis if the encoder was bad. What does the fault error say?
That thread is definitely TL;DR, but I skimmed through it..I would highly recommend dropping the idea of a retrofit or changing Hurco's design. If you arent prepared to troubleshoot a problem like this, retrofitting is an order of magnitude more difficult and expensive.
So lets get down to basics, the homing problem.
I take it at this time, the machine homes on all axis correctly, except Y axis?
Questions:
Can you feed the Y axis without homing (watch out, dont hit the physical stops)?
And if so, does it move smoothly and at the selected feedrate?
)