On 7/14/24 04:12, Viesturs Lācis wrote:
Hello!
I was asked about possible retrofit of Deckel FP4MA milling machine.
I found several forum threads about these machines and everything
seemed clear to me except that the machine I saw has one motor for Y
and Z axis - there are hydraulic clutches that select which axis to
move, but I did not notice such a setup mentioned in other retrofits.
Yee gods. I get a headache just thinking about a 5000 line file would
need 4k fixes. Is the machine accurate enough to fool with trying to
salvage it? If it is, The first outline would be to toss the clutches
and make individual motors so that worry goes away forever. The second
pass would swap cheap steppers for stepper/servo's.
So I wanted to ask if anyone has done that previously and how to
handle that in config. Can those clutches be operated automatically or
would that require some M commands in g-code file (special attention
would be needed to make sure that g-code does not contain moves for Y
and Z simultaneously)? I cannot imagine how to handle it automatically
because there might be attempts to blend motion in YZ plane.
The stepper/servo's contain their own SMART pid's that linuxcnc need not
be aware of as they can take the step-gen output connected directly to
motion. The controller uses the error signal magnitude to adjust the
motors current on a step by step basis so they run enough cooler you can
see it in the power bill. That is advantage #1. #2 is the tightness of
control, if the motor overshoots by one micro-step, the controller will
reverse it, so accuracy at higher speeds is amazing. #3 is that if the
motor hits something that impedes its movement, the controller will see
the error and use every milliamp the supply can supply to prevent that
loss of a step. The controllers have an output that you can toggle f2
with killing linuxcnc in the next millisecond if a step is lost. And the
cost premium has jumped off a cliff in the last year, to about $20 an
axis. I have 5 of them in service in by garage, will be 8 before snow
fly's again, and 4 more driving XY on a pair of 3d printers. The
printers are 10x faster than OOTB 2 years ago.
That of coarse circles back to the machines condition. Compare that to
the cost of a machine that can replace it. Check with Hanpose for
motors and controllers. Controllers rated to 100+ volts.
Viesturs
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users
.
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
