On 1/11/25 20:18, John Dammeyer wrote:
Thanks Andy,
I'll try that. Just finished reworking these heat sinks to have slightly
deeper pockets to clear the capacitors on the PC board.
tps://youtu.be/tn1n2XQ3VIo
One day I must really change the spindle drive so it doesn't rattle on the
splines and changed to a toothed belt. The motor pulley that I cast and
machined is a hair too large for the motor shaft and so has the slightest
wobble. The closed loop from the spindle encoder with non-symmetrical teeth
and the wobbly motor pulley seems to make the LinuxCNC spindle closed loop
speed not great at 2950 RPM. Barely gets up to speed and then oscillates
around the set point.
All things considered at least I got the job done.
John
Another way (the rattle is often because the encoder feedback is too
coarse) is to improve the encoder definition. I had a shop made optical
with 64 slots per rev, and my spindle sounded like every ball in the
bearings was square, a very worrisome racket. So I made an extension on
the rear of the motor shaft to drive an Omron 1000 ppr encoder mounted
on the rear of the motor. But left the index on the spindle. The Omron
had a balanced output which I turned to TTL by a couple $2.00 rs485
translators. That was too fast for the parport cards opto's, so I moved
that to the 5i25's encoder which has no glacial opto's. Then I put a
couple switches on the go704's gearshift knob to tell LCNC which gear it
was in. I now get 3000 revs in high, or 1500 in low with a switch in hal
to change the scale, which is a bit over 7000 in high gear, and a bit
over 14,000 in low gear.
This totally got rid of the servo slapping the gears around, which is
what was making all the noise. Wasn't square bearings at all.
Now the only noise is the iron in the motor when the pico pwm-servo
limits motor current to 18 amps at 125 volts, around 3.5 hp out of the
motor rated for 1 hp by grizzly. That's a low level squeak I have to
listen carefully to hear. I've wore out too many rifle barrels. Been
running that way for 15 years. And still on the OEM brushes. Whats not
to like? I'd be glad to PM you my configs If you want to see them. They
may not be purty, but they work.
Cheers, Gene Heskett, CET.
--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users
