Sieg KX3

The KX3 is a relatively common mini-mill available through several distributors, including Arc Eurotrade [1] and Harbor Freight [2]

The purpose of this howto is to provide sufficient information to allow KX3 owners to control their mill using EMC2. This howto is not complete, and should be considered guidance only.

Installing EMC2

This is described under the section Installing EMC2. This howto will assume EMC version 2.2.7 is installed.

Configuring the Beast

• The KX3 uses a C11G I/O card from CNC4PC. [3]

• The I/O card utilizes a "charge pump" input signal in order to enable the motor controllers. A 12.5kHz signal from the controlling software (EMC2) must be present, or the machine is shut down. This is a useful safety feature, because it prevents a software fault or exception to accidentally activate the mill. It also prevent the mill from going crazy during the PC boot-up process, when your parallel port signals could be undefined.

• Note that the KX3 emergency stop output signal is active whenever the charge pump enable is not present. And the default configuration of STEPCONF does not enable charge pump unless the ESTOP signal is inactive. Catch-22 ensues.

• We shall correct this directly in the HAL file, were we simply allow EMC2 to to output the Charge Pump signal regardless of the ESTOP input.

• The following crude HAL and INI configuration files should work. They are not necessarily "correct", but appeared to work at the moment at the time of publication of this howto.

• I will spend more time updating this as I get more comfortable with the system. I might also do a step-by-step tutorial using STEPCONF.

Sample KX3.INI configuration file

Notes

• This assumes a default installation.
• USERNAME should be replaced with your username to obtain the correct path.
• Paste the following into a file called KX3.ini and place in the configuration file directory.
• This file was originally generated by STEPCONF.

[EMC]
MACHINE = KX3
NML_FILE = emc.nml
DEBUG = 0

[DISPLAY]
DISPLAY = axis
EDITOR = gedit
POSITION_OFFSET = RELATIVE
POSITION_FEEDBACK = ACTUAL
MAX_FEED_OVERRIDE = 1.2
INTRO_GRAPHIC = emc2.gif
INTRO_TIME = 2
PROGRAM_PREFIX = /home/USERNAME/emc2/nc_files
INCREMENTS = 5mm 1mm .5mm .1mm .05mm .01mm .005mm
PYVCP = panel.xml

[TASK]
TASK = milltask
CYCLE_TIME = 0.010

[RS274NGC]
PARAMETER_FILE = emc.var

[EMCMOT]
EMCMOT = motmod
SHMEM_KEY = 111
COMM_TIMEOUT = 1.0
COMM_WAIT = 0.010
BASE_PERIOD = 30000
SERVO_PERIOD = 600000

[HAL]
HALFILE = KX3.hal
HALFILE = custom.hal
POSTGUI_HALFILE = custom_postgui.hal

[TRAJ]
AXES = 3
COORDINATES = X Y Z
LINEAR_UNITS = mm
ANGULAR_UNITS = degree
CYCLE_TIME = 0.010
DEFAULT_VELOCITY = 7.00
MAX_LINEAR_VELOCITY = 70.00

[EMCIO]
EMCIO = io
CYCLE_TIME = 0.100
TOOL_TABLE = tool.tbl

[AXIS_0]
TYPE = LINEAR
HOME = 0.0
MAX_VELOCITY = 65.5172413793
MAX_ACCELERATION = 400.0
STEPGEN_MAXACCEL = 500.0
SCALE = 500.0
FERROR = 1
MIN_FERROR = .25
MIN_LIMIT = -2.5
MAX_LIMIT = 280.0
HOME_OFFSET = -3.000000
HOME_SEARCH_VEL = -50.000000
HOME_LATCH_VEL = 5.000000
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = 1

[AXIS_1]
TYPE = LINEAR
HOME = 0.0
MAX_VELOCITY = 65.5172413793
MAX_ACCELERATION = 400.0
STEPGEN_MAXACCEL = 500.0
SCALE = 500.0
FERROR = 1
MIN_FERROR = .25
MIN_LIMIT = -2.5
MAX_LIMIT = 110.0
HOME_OFFSET = -3.000000
HOME_SEARCH_VEL = -50.000000
HOME_LATCH_VEL = 5.000000
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = 2

[AXIS_2]
TYPE = LINEAR
HOME = 275.0
MAX_VELOCITY = 65.5172413793
MAX_ACCELERATION = 400.0
STEPGEN_MAXACCEL = 500.0
SCALE = 500.0
FERROR = 1
MIN_FERROR = .25
MIN_LIMIT = 0.0
MAX_LIMIT = 275.001
HOME_OFFSET = 275.000000
HOME_SEARCH_VEL = 50.000000
HOME_LATCH_VEL = -5.000000
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = 0

Sample KX3.HAL configuration file

Notes

• This assumes a default installation.
• Paste the following into a file called KX3.hal and place in the configuration file directory.
• This file was originally created using STEPCONF, and then modified to resolve the ESTOP issue and to add a 5th stepper generator controlling the spindle.

loadrt trivkins
loadrt [EMCMOT]EMCMOT base_period_nsec=[EMCMOT]BASE_PERIOD servo_period_nsec=[EMCMOT]SERVO_PERIOD traj_period_nsec=[EMCMOT]SERVO_PERIOD key=[EMCMOT]SHMEM_KEY num_joints=[TRAJ]AXES
loadrt probe_parport
loadrt hal_parport cfg=0x378
setp parport.0.reset-time 3000
loadrt stepgen step_type=0,0,0,0,0 ctrl_type=p,p,p,p,v
loadrt charge_pump
loadrt scale
net estop-out iocontrol.0.user-enable-out #Charge pump must not be connected to ESTOP!  
net charge-pump <= charge-pump.out


addf parport.0.read base-thread
addf stepgen.make-pulses base-thread
addf charge-pump base-thread
addf parport.0.write base-thread
addf parport.0.reset base-thread

addf stepgen.capture-position servo-thread
addf motion-command-handler servo-thread
addf motion-controller servo-thread
addf stepgen.update-freq servo-thread

setp scale.0.in 0

# adjust spindle speed here if required
setp scale.0.gain 0.9

# The suggested gain was not scientifically tested, but based on the motor speed maxing out at approx S3500, which is the theoretical maximum for a KX3. 

setp scale.0.offset -50 
# A negative offset appears to yield the best results for low speeds allowing for approx 60 rpm at S60. 

addf scale.0 servo-thread
setp stepgen.4.position-scale 1
setp stepgen.4.maxvel 3500 # maximum for standard KX3
setp stepgen.4.steplen 1
setp stepgen.4.stepspace 0
setp stepgen.4.dirhold 20000
setp stepgen.4.dirsetup 20000
setp stepgen.4.maxaccel 2000

net spindle-enable <= motion.spindle-on => stepgen.4.enable
net spindle-cmd motion.spindle-speed-out => scale.0.in 

net spindle-freq <= scale.0.out => stepgen.4.velocity-cmd 
net spindle-out <= stepgen.4.step => parport.0.pin-14-out 

net spindle-cw => parport.0.pin-16-out


net xstep => parport.0.pin-02-out
setp parport.0.pin-02-out-reset 1
net xdir => parport.0.pin-03-out
net ystep => parport.0.pin-04-out
setp parport.0.pin-04-out-reset 1
net ydir => parport.0.pin-05-out
net zstep => parport.0.pin-06-out
setp parport.0.pin-06-out-reset 1
net zdir => parport.0.pin-07-out
net astep => parport.0.pin-08-out
setp parport.0.pin-08-out-reset 1
net adir => parport.0.pin-09-out
setp parport.0.pin-14-out-invert 1
net charge-pump => parport.0.pin-17-out

net estop-ext <= parport.0.pin-10-in
net both-home-x <= parport.0.pin-11-in-not
net both-home-y <= parport.0.pin-12-in-not
net both-home-z <= parport.0.pin-13-in-not

setp stepgen.0.position-scale [AXIS_0]SCALE
setp stepgen.0.steplen 1
setp stepgen.0.stepspace 0
setp stepgen.0.dirhold 40000
setp stepgen.0.dirsetup 21000
setp stepgen.0.maxaccel [AXIS_0]STEPGEN_MAXACCEL
net xpos-cmd axis.0.motor-pos-cmd => stepgen.0.position-cmd
net xpos-fb stepgen.0.position-fb => axis.0.motor-pos-fb
net xstep <= stepgen.0.step
net xdir <= stepgen.0.dir
net xenable axis.0.amp-enable-out => stepgen.0.enable
net both-home-x => axis.0.home-sw-in
net both-home-x => axis.0.neg-lim-sw-in
net both-home-x => axis.0.pos-lim-sw-in

setp stepgen.1.position-scale [AXIS_1]SCALE
setp stepgen.1.steplen 1
setp stepgen.1.stepspace 0
setp stepgen.1.dirhold 40000
setp stepgen.1.dirsetup 21000
setp stepgen.1.maxaccel [AXIS_1]STEPGEN_MAXACCEL
net ypos-cmd axis.1.motor-pos-cmd => stepgen.1.position-cmd
net ypos-fb stepgen.1.position-fb => axis.1.motor-pos-fb
net ystep <= stepgen.1.step
net ydir <= stepgen.1.dir
net yenable axis.1.amp-enable-out => stepgen.1.enable
net both-home-y => axis.1.home-sw-in
net both-home-y => axis.1.neg-lim-sw-in
net both-home-y => axis.1.pos-lim-sw-in

setp stepgen.2.position-scale [AXIS_2]SCALE
setp stepgen.2.steplen 1
setp stepgen.2.stepspace 0
setp stepgen.2.dirhold 40000
setp stepgen.2.dirsetup 21000
setp stepgen.2.maxaccel [AXIS_2]STEPGEN_MAXACCEL
net zpos-cmd axis.2.motor-pos-cmd => stepgen.2.position-cmd
net zpos-fb stepgen.2.position-fb => axis.2.motor-pos-fb
net zstep <= stepgen.2.step
net zdir <= stepgen.2.dir
net zenable axis.2.amp-enable-out => stepgen.2.enable
net both-home-z => axis.2.home-sw-in
net both-home-z => axis.2.neg-lim-sw-in
net both-home-z => axis.2.pos-lim-sw-in

net estop-out <= iocontrol.0.user-enable-out
net estop-ext => iocontrol.0.emc-enable-in

loadusr -W hal_manualtoolchange
net tool-change iocontrol.0.tool-change => hal_manualtoolchange.change
net tool-changed iocontrol.0.tool-changed <= hal_manualtoolchange.changed
net tool-number iocontrol.0.tool-prep-number => hal_manualtoolchange.number
net tool-prepare-loopback iocontrol.0.tool-prepare => iocontrol.0.tool-prepared

Starting the Beast

That's it! You should now have basic control of the three axes and the spindle from EMC2. It is advisable to do all initial testing with a "safe" Z-axis height, and with one hand close to the emergency stop.

Contributions

This page was originally written by Thorium?. Feel free to improve the content, or contact me if you would like to discuss.