Hi Guys:
Well, lets see what it says..
>>Mon - 22:31:31 ---Spindle Lock: 4721 , Total Ints: 0, Total Spindle Ints: 0, Error: 728, Adder: 0 LastRot: 5830
Mon - 22:31:31 ---Spindle Lock: 4721 , Total Ints: 5221, Total Spindle Ints: 4721, Error: 500, Adder: 0 LastRot: 5964
Mon - 22:31:31 ---Spindle Lock: 4721 , Total Ints: 10606, Total Spindle Ints: 9442, Error: 1164, Adder: 0 LastRot: 5876
Mon - 22:31:31 ---Spindle Lock: 4721 , Total Ints: 15426, Total Spindle Ints: 14163, Error: 1263, Adder: 0 LastRot: 6009
Mon - 22:31:31 ---Spindle Lock: 4721 , Total Ints: 20116, Total Spindle Ints: 18884, Error: 1232, Adder: 0 LastRot: 5937
.....
Ok, so the spindle was seen to be running at 4721 interrupts per rotation with no load just prior to threading..( thats what the spindle lock means). Not sure of your interrupt freq., assume its 25K so you have
40us per int so .188 seconds per rot for 5.29 per second or approx 320RPM. ( again, assuming 25K interrupt time, always use the lowest interrupt freq you can get away with for stabilities sake..).
Then you started the trhead. Amazingly it ran slow even before it hit the material.. it took 5221 on the first pass, so Mach likely slowed the axis to compensate..it kept slowing every rotation as the
error kept building. It never really catches up to the expected time. Really, the Total Ints number should try to stay near the Total Spindle Ints. Mach tries to slow things down to make that so. The number
under Error: is the actual number Mach uses to slow down. So its slowing every rotation and by a variable amount.
Try running a thread in the air, the numbers should be much closer.( Total Ints: *********, Total Spindle Ints: yyy, ) If they are not , then you probably have either noise ( because of a 3..5 volt port maybe being ore sensitive?), or the interrupt
on that pc isnt very stable. Your driver test should display spikes or other patterns instead of a straight line if thats so. The printout seems to simply show that Mach doesnt seem to be able to track very
closely though it IS trying to. The problem seems to be there is too much variation. Id suspect noise or PC interrupt stability as the root issue if the threads wander..
Art