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Topics - ptegler

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1
General Mach Discussion / Very odd Homing event after rotary axis install
« on: October 12, 2014, 12:09:41 AM »
After installing a rotary axis on my CNC router table I ran into a BIG problem.
http://www.youtube.com/watch?v=KklafqyZpSY

I swapped out the A axis (slaved on the gantry for the Y axis) and configuring the B axis as the slave to the Y motor.
After going through the motor tuning to reconfigure the motors and set up the A axis as a rotary and matching the B motor settings to the Y axis motor settings (replacing the A as slave)  allowed me to get the A axis up and running just fine as the rotary axis.

I added an optical reflector coupler as the homing switch for the rotary axis. Works great! Painted a pulley flat black then just scratched the paint off for a shiny marker for the opto switch.

 :o NOW HERE's  THE ODD issue.  :o

After pressing the REF ALL HOME button on the main screen the Z axis homed then backed off the switch as expected.
Then the Y axis (with it's newly configured B motor as a slave) home properly.
Then the X axis homed properly, then the rotary axis rotated back towards zero and then backed off a couple degrees as expected.

BUT  and a BIG BUT.... the B motor then attempted to home by itself ...
Luckily the motors are all spring loaded against the rack and pinion drives. The B motor commenced over powering the spring (which is pretty friggin' tight)  and banging the heck out of the gantry as the gear slipped past the rack teeth trying to rack the gantry as the Y motor was not being driven.

So homing and moving the Y axis (moving the gantry down table and back jogging without issue... B as the slaved motor)
BUT the REF ALL HOME tried to home just the B axis after properly working as the slave on the Y !!!!

OK...so what did I miss not setting up correctly??? Macro under the REF ALL HOME button? some other config screen?

I've attached my  ROUTER111.XML file if some can spot something/figure out what's amiss I'd REALLY appreciated it.
Everything else seems to work as expected.

ptegler

2

...sorry for the double post....

My backlash for 1" moves of 40" moves is within 0.0002" repeatability on x and Y axiz
(on a 28" x 48" working area)  slaved 900oz/in motors on the Y axis single on the X axis.
But whether it's a 1" diameter circle or a 8" circle... they are all out of round by 0.030"
What I think is over tightening the bearings/slides/screws/R&P parts....then a retest.... it's always 0.028-0.030" out of round on the same axis, (11 o'clock down 5 o'clock is narrower by 0.030)   regardless of climbing or normal routing directions.

This was tested with several circles inside each other, each running in the opposite directions.
ALL are out of round. so I even rotated the MDF test board just to validate it was not material stress related.
There is no (zero) racking (twin 900 oz/in motors) which might have made sense if backlash on one side were greater than the other
(trapazoidal resultant motion or reversal along the X axis is  the Y axis racked)

hhhmmmm... should my dual motor Y axis acceleration setting be twice the single motor X axis?
or perhaps half the X axis to compensate for power to weight of the gantry vs just the head on the X....
(or am I over thinking all this)

Now I know I read somewhere on these forums there is a difference possibly in absolute stop vs continuous speed....circle interp etc
An example visible to anyone is while making my dust shoe, one circle seemed to start and stop a lot, while others were a continuous motion/sound
This is visible at  https://www.youtube.com/watch?v=gr6VAfZCQlo
at the 1:54 mark you can here it starting and stopping cutting hard i nthe material, yet later circles are smooth and conitnuous.
I did not do anything different.... straight conversion from VCarve Pro to g-code, yet this one circle cut with the start/stop sound.

The MDF circle tests done a couple months ago now still bugs me as I've not been able to formulate any real logistics to hunt down, other than settings for the way MACH3 should/can be config'ed to cut circles.

for reference...the whole machine...  https://www.youtube.com/watch?v=KklafqyZpSY&list=UUNTCxkF_0pxnMa-g9HTVgxA

Any clues here as to where I should start testing to re-config this machine for clean round circles?

tia

ptegler

3
*****VIDEOS***** / New Touchscreen Controller is mounted
« on: February 28, 2013, 06:27:46 AM »
Just short update on my Mach3 CNC Custom Controller running my Smithy Granite 1324 Mill/Lathe
touch screen, pokeys keyboard, 3 MPGs (two are pseed/feed controls and the mounting arm

Mach3 CNC Custom Controller running my Smithy Granite 1324 Mill/Lathe




ptegler
www.teglerizer.com

4
PoKeys / mapping to the lastest MACH3 version
« on: February 08, 2013, 09:10:06 PM »
 ???This has been my issue of late... mapping  potentiometers on the analog inputs of a Pokeys 56U to control FRO and spindle in MACH3.

MPG (on encoder #1 ins) moves the FRO (not very well...12 bit not 10 bit like the 55 so the numbers/ratios are all wrong) but not the analogs. ::)

On the 55 there are comments all over this board regarding mapping to the G100 modbuss 124-127
But on the Pokeys 56U there are more analog out ports... starting at a lower pin number.
So...WHAT is the proper mapping of the analog outs of the 56U to the ports as compared to the G100 124-127 registers comments and brains examples here.??
What is MACH3 looking at to see the analog ports of the Pokeys 56U??   ???

The analog outs of the pokeys56U are all visible (and functionally changing) within the plugin configutation screen from inside MACH3.
But MACH 3 does not see them .... the mapping is simply not controlling the FRO or spindle controls in MACH3

Can someone layout in one place, the complete info to do this mapping with the latest Pokeys 56U (and its latest plugin) and the latest version of MACH3
thanks to all of you, for all the help thus far and the fantastic resources supporting this software platform.

Apparently the mapping of the latest MACH3 is not seeing the latest plugin config.

 

Paul Tegler

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