Topics

1

Mach3 and G-Rex / more issues with Grex

« on: November 16, 2013, 02:52:31 PM »

Im trying to set up G100, with latest mach3, latest firmware, latest fpga ....
something wired is happening
I cant set up active low, or active high on step pin, it is working random, some time stop at high, some time low level
also moving axis is strange
if X is 0 and I type X1 it go to 0.87 or similar, then I type second time X1 and then finally go to X1
later I type X0 and it go to X 0.14
at this point if I move axis Z manually then X go to 0 by itself

charge pump is very low frequency, about 2-3-4 Hz, cant enable the controller, need few Khz

why so many strange things happening?

 

2

Mach3 and G-Rex / G100 + step/dir spindle and rotating axis

« on: November 13, 2013, 05:35:59 AM »

currently Im using parallel port with step/dir spindle, where I have identical port/pin settings for spindle and axis A so I can use it as spindle or rotating axis same time, it is working fine, just need to pay attention at G code, while one is used the other must be zero speed
I have one G100 sitting around and I thought I can use it for more stable pulsing for step motors, but I cant make same setting
anyone can help?
thanks

3

General Mach Discussion / how to avoid T/M commands execution delay

« on: March 08, 2013, 08:22:08 AM »

hello everyone
currently Im trying to optimize very short lathe G code
total time 40 seconds then a bar puller is used to continue again and repeated many times
in that G code I have several times tool change and several times coolant on/off
I noticed that tool change and M8/M9 commands delay slightly but when many times used cause significant delay
I think currently I loose about 5-6 seconds total,  which is 10-15% time waste, how to avoid that delay?
thanks

4

General Mach Discussion / mach3 turn - changing front/rear post wrong offset

« on: April 08, 2012, 02:10:21 PM »

Im I something wrong? it looks like when I change front/rear tool post something wrong is going on with the offset
when I set tools from front post only - working
when I set tools from rear post only - working
BUT when I change front and rear post - something terribly wrong happened

the only way I found to change front and rear is to change first to a tool with zero offset from front post, then to a tool with zero offset from rear post, and then I can use tools from rear post, then to go back to front post I have to change tools with zero offset in opposite way
why is that ?!?

5

Feature Requests / CV bad behaviour need improvement

« on: March 07, 2012, 08:50:37 AM »

hello
finally I found a spindle with higher RPM and endmill which allow me to increase the feedrate
unfortunately I found several problems with CV mode when feedrate increased over 3m/min
in some situations it have terribly badly behavior where step motors will definitely loose position
Im using servo drive where sudden stop with lower speed is executed relatively well, the whole machine is shaking and vibrating badly where high elastic deformation occur in my construction but the machine continue and I can observe what is happening

so here is my configuration
maximum speed on X and Y axis - 15 m/min
acceleration - 0.4s to reach maximum speed
CV distance 1mm
CV angle 10 degrees

what I found is that CV angle in not as shown in CV notes

please see the attached file

on second and third image Gcode points are shown with circles, where the distance between each point is slightly lower than CV distance - 1mm
if no sudden stop occur then the rounding is obvious

after sudden stop is fixed I think rounding can be reduced significantly and keep high speed if more options are added:

if CV angle < 1 degrees then CV distance = 10mm
if CV angle < 2 degrees then CV distance = 5mm
if CV angle < 5 degrees then CV distance = 2mm
if CV angle < 10 degrees then CV distance = 1mm
if CV angle < 20 degrees then CV distance = 0.1mm
if CV angle > 45 degrees then CV off - exact stop or plasma mode
if not possible to keep same speed in next 10 or 50 lines then start deceleration early or exact stop on next point and then start over with CV or any similar algorithm

all numbers need to be entered manually for any specific machine and configuration


I guess even if you found a good ideas will take long time to fix it
is there any chance I can improve it myself? probably with custom brain or something else which can be done quickly than waiting for next release?
please advice
thanks

6

General Mach Discussion / mach on neoware PC keep crashing

« on: September 25, 2011, 04:51:04 AM »

hello everyone
I bought second hand mini PC
neoware CA19 or C50
it is a very small PC but it is complete with all needed, it is 400mhz processor but also 400 FSB which make it really fast when no calculations needed, because it is small I thought I can use it for driving one mini cnc machine, the chipset is CN700

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c01295775&lang=en&cc=us&taskId=101&prodSeriesId=3638790&prodTypeId=12454

upgraded with hard drive, windows XP sp2, installed chipset and video drivers
I tried both ways to install windows, standard way and pressing F5 and all other settings explained in "optimizing" windows
but mach cannot work properly, keep freezing and crashing
please advice what else I can try

7

General Mach Discussion / modbus schematic or similar

« on: November 11, 2008, 07:06:57 PM »

hello
Is there free or open source working schematic and firmware for Input/Output expansion board for mach3? I need more inputs on usb or serial port will be perfect
thanks

8

General Mach Discussion / vinyl cutter?

« on: July 10, 2008, 01:30:01 PM »

hello
I'm just looking for vinyl cutter blades, and they all have an offset about 0.25-0.5mm, they work in blade holder with bearings, so 4-th axis is not necessary , this offset helps blade to find the proper direction, the only problem is how to set mach3 to work with this offset. the problem appear in changing directions - on 90 degree corner the blade cut small raduis, and mach3 should compensate this
any ideas?
thanks

9

Mach3 and G-Rex / g100 and e-stop

« on: July 20, 2007, 10:40:16 AM »

hi all
i have a problem with g100, probably my mistake but if somebody can help will be nice
last lock down version mach3, with last version g100 plug in, last version firmware and fpga settings uploaded to g100,
then i set digital input 16 to be e-stop, and digital output 1 - spindle
look fine, spindle on-off-on-off no problems, then i press e-stop button ( digital input 16 connected to ground ), then release e-stop button, then with mouse i press reset button on the screen, mach3 is ready
after this i can run spindle only once, second time dwell light is on, to continue work i have to restart mach3 or g100

10

General Mach Discussion / about Z depth

« on: June 24, 2007, 07:06:19 PM »

hello everyone
i'm trying to do something unusual....
for example: wood cutting router , cutting 2.5d square on flat surface - easy
but... if the surface is not exactly flat... and z depth is 1mm - big trouble
what i can do?
for now i have 2 ideas but i dont know how to...

1. using up and down inputs ( for plasma height regulation ) but this idea need very precision switches very close to the tool where wood chops can make troubles, or when changing direction
2. using scanner - first run g-code for square with scanner,scan only the square periphery (not raster) and make corrections on z axis only, then run the new g-code with tool

i think the second one is better, also the tool and scanner could be used without changing

               tool               scanner
________________________________________________
                  |                    |
                                 ******************xx

the question is: how to realize this?