Hi:
Lets take these one at a time...
>
I got my steppers to work with Mach2, but I'm having
dificulty 'tuning' them for speed and distance (accuracy). The
motors are 1.8 deg/step, so thats 200 steps per rev. With a
leadscrew pitch of .0625 (1/16"), then my steps per unit (inch)
should be 200 X 16 = 3200 right?? My motors' shaft only turns a tiny
bit (~30 degrees) on a .0625" MDI move. If my math is correct, the
motor should turn a full revolution to get .0625" assuming a 1 to 1
direct drive of the leadscrew and 16 revs for a 1.000" move. What am
I doing wrong?
You must be using microstep drivers of some sort. Perhaps 10 uStep woudl
explain it. Then it woudl be 2000 * 16 = 32000 / inch/ This would also
explain the 30 (36?) degree movement for 1/16".
During velocity tuning it seems that the motors stutter a bit (no
load, just sitting on the bench) at high and at very slow speeds.
Its not good to tune motors with no load. Some drivers will jitter without
a damping force of some sort..
> believe stepper speed is directly relative to Voltage (of which I'm
definitely lacking). However, I'm not sure if I'm seeing lost steps,
or if there is a timing/signal problem keeping the motion from being
smooth and consistent. This could easily be a problem with my
drives/lack of voltage, but was curious if varying frequency timings
could cause this, see next question.
Yes, next question probably explains it..
I'm also curious about the frequency settings 25,000 khz, 45,000
khz etc... Considering my low performance stepper system, but fast
1.73Ghz CPU, what frequency should I be using? How do these
frequencies affect steppers max velocity, loosing steps/stalling
etc...? Or are the faster frequencies only for running high
performance systems capable of 100+ IPM??
35K and 45K modes are used by people who need higher speeds. In other
words , when they tune, the velocity is maxed and they'd like more.
Generally, unless your velocity is Maxed when tuning, stay at 25Khz, its
less of a drain on the Windows system.
Also, I noticed at
25,000khz the OCX driver test shows wildly varying numbers, mostly
much lower than 25,000khz. Do I have a Windows/motherboard/Mach2
driver problem or something or is this normal?
How wildly?? Generally, you should be around 25000, but only vary as much
as a hundred or so. If its going from 20,000 to 25000 for example, this is
too wild a swing and somethign is interfering.. This type of swing would
generally be an application, or a network card interrupting too much. Let me
know the swing your getting, it may point us somewhere...
Thanks,
Art
