GearHeads Corner

Hello everyone. So , is my first post here obviously , and from totaly "0" knowledge of CNC machines or GCODE i start to build my own laser engraver ,cutter, whatever will be  :o.
First thanks to Art and tweakie for first advices what i should buy and try for laser engraver. Initialy i want to build for my wife and fun but after time passing , i take it personaly, is alot of learn about CNC machines and that keep me interested on.
Good things and bad things about my start always are, of course.
Good one's has, i just start without any schematic and i just adjust everything in work procces. I buy newma 23 2.0n clossed loop stepper , pokeys57CNC and of course auggie . Start like a charm. I didn't finish to install the laser yet but i hope i managed to calibrate the steps ,axes, everything. Some limits switch missing but soon will be done too. I manage to learn how to tune and set in pokeys ......i'm up,,, i think  ::)
Bad things , i didnt realy understand how all GCODE comands work " time is to short " to much information on strange field for me .
Second , i don't manage to install augie correctly on lenovo w530 64bit win7 pack1, i7.8G ram, SSD. I got some strange error on start to install auggie " this program stop" and after windown recover the problem and install work correctly, probably my stupid antivirul open in sandbox first. But it work.
Other thing is , until 2 min of trying push Estop i got engaged, disengaget message and i need to push again Estop until 20 times to get working. That happen only on network, USB work perfectly. I try in bridge, DHCP router only and home router linksys EA6900 , fixed IP, private class, everything. Probably is misssconfiguration in profile , i dont know.
Other is PWM, i didnt manage to try on others pins, but is engaged on analog out at 17 i think 0-10v, still dont have time to measure everything correctly. That in the feature. I read here to use others pins from trusted user , tweakie.
I'm electronic engineer, ASM , C programmer but is first time on CNC mashining, is alot to learn and ...
So that's it..... i'm up
I put some pictures below , and ignore the mess, is for everyone of as who learning.....
Critics are welcome and sry for my poor english
Still i didn't figure out how to load DXF in auggie for cutting and in wich program i should use to build the vector

Bobby:

  Well , your off to a good start being that you managed to tune your steppers and such.

>>Other thing is , until 2 min of trying push Estop i got engaged, disengage t message and..

  Check your network delay setting in the final page of axis settings. Some need 1, some need 0
in that setting for network use.

>>Still i didn't figure out how to load DXF in auggie for cutting and in wich program i should use to build the vector

  You can load a dxf into Vexx and select all contours, then edit/group, then press the quickGcode button. This
will put out code for lasers from a dxf. Auggie will only load photos to make Gcode from, not dxf's. It will load
Vexx's Gcode though.


  Yell when confused..

Art

Hi Bobby,

Will it be a CO2 laser that you are installing and what is the wattage ?

Tweakie.

Hi Bobby!

Welcome to the forum!  I don't know means you realize there's always more to learn, and despite some occasional frustration that's where the fun is.  Keep us posted on how you're doing, and don't forget those safety glasses, only takes seconds to ruin your eyes.

Hi Tweakie!  When did you add a forum to your site, and is that a new host?

Kirk

Hi Tweakie!  When did you add a forum to your site, and is that a new host?

Hi Kirk,

I had to change website hosting following a change of policy by my service provider. The website was added just so that different 8 bit image laser engraving techniques could be discussed but unfortunately there has been little or no interest.

Tweakie.

tweakie wrote: Hi Bobby,

Will it be a CO2 laser that you are installing and what is the wattage ?

Tweakie.

Is 80w tube, same the source. I test recently to adjust maximum current alowed , to dont damage the laser, and i notice , the laser source on TTL input have a residual internal voltge at 600mv. That will turn laser on with alot of power(without input signal). Also at 2.4V input i reach 22mA. That is normal or the power source dont work corectly?
Thanks

Hi Bobby,

Could you perhaps post some details of your laser PSU / controller ?

Tweakie.

Hi:

yeah, its hard to tell whats up without knowing how its hooked up.
The PWM puts out a tickle voltage which yours may not need, so you may want to set tickle at 0 in the settings.
But then there should be no voltage when laser is off..

Art

tweakie wrote: Hi Bobby,

Could you perhaps post some details of your laser PSU / controller ?

Tweakie.

Yes sure. I didn't think on that, sry.  :(
The source is this one https://www.aliexpress.com/item/911254124.html?spm=a2g0o.productlist.0.0.490f6f3e9u1QMx&algo_pvid=15f05b4c-2cb1-45f9-900e-8eb87797684d&algo_expid=15f05b4c-2cb1-45f9-900e-8eb87797684d-2&btsid=c82436b8-a867-4703-8316-1c5aa42280ac&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_52

and laser is this one https://www.aliexpress.com/item/32784065931.html?spm=2114.12010612.8148356.4.2ce43a39J6FNuq

will open the source this weekend to see what is the problem , or just working like that , i dont know. But normaly , any input should offer more high impedance possible with 0 residual voltage .
Thanks

I think a simple test would be to disconnect anything connected to the TTL(H) and TTL(L) terminals of the PSU.
If the laser still fires try fitting a pull-up resistor (10k) between TTL(L) and +5V and a pull-down resistor (10k) between TTL(H) and GND.
If the laser still fires then you have a problem with the PSU.

Sounds right to me. Usually a TTL high and TTL low are just inputs to an optocoupler,
so with nothing hooked up you should get zero output..

Art

tweakie wrote: I think a simple test would be to disconnect anything connected to the TTL(H) and TTL(L) terminals of the PSU.
If the laser still fires try fitting a pull-up resistor (10k) between TTL(L) and +5V and a pull-down resistor (10k) between TTL(H) and GND.
If the laser still fires then you have a problem with the PSU.

Is not connected yet on any pin of PSU. I just made some tests. Seems the PSU input TTL \L/H are very low impedance .
Now i have two problems , First , only below 1k resistor will turn off completly the laser , and that's bad, will be necessary to change entire input circuit and design the second one.
Second is , because i want to made the limit on maxim 60w of my laser. I buy on 80w just to don't stress him on max power. So that will be a little bit tricky , wil dont work only with some resistors and transistors.
Anyway , seems to be good , i made some test on a simple square in Auggie of course, and look very nice (without cut it, are not all the mirrors placed ) , and i saw the auggie calculate the laser power according with speed and velocity on corners ,i attach a photo.
Still i have a question . Why i never reach the maximum 3V voltage during cut operation ? In pokeys work perfectly , from 0 to 2.92v and that's normal. I miss some configurations ?
And my second question  is on cutting operation, like example i cut two circles , the cutting speed is more high than travel speed between cuts . Is that normal ? Sry , i don't realy know to much about CNC , is new zone for me . :-[

Hi:

>>Why i never reach the maximum 3V voltage during cut operation ? In pokeys work perfectly , from 0 to 2.92v and that's normal. I miss some configura tions ?

  Auggie corrects for speed vs power in order to stop burning in corners. The formula though is  (actual speed) / ( feedrate commanded) * power. So if you set F50 and it reaches 50, you get 100% power. IF you command 2000 and it only reaches 100
you get very little. You adjust your feedrate command to the maximum the axis actually hit and it will hit 100% of commanded speed.


>>And my second question  is on cutting operation, like example i cut two circles , the cutting speed is more high than travel speed between cuts . Is that normal ? Sry , i don't realy know to much about CNC , is new zone for me .

  Travel speed should be the highest you can do. Its a g0 move, which means rapid. A g1 move is at feedrate and feedrate
will never go higher than rapid can. But..its hard to say how your code was written, it may be the Gcode your using is commanding it. If you show us the code I can tell you.

Art

ArtF wrote:   Travel speed should be the highest you can do. Its a g0 move, which means rapid. A g1 move is at feedrate and feedrate
will never go higher than rapid can. But..its hard to say how your code was written, it may be the Gcode your using is commanding it. If you show us the code I can tell you.

So, what i understand , i need to have at maximum desired speed feedrate "100" , and on my is 6000. That's mean , he will never reach 6000 and the power percentage will be something like 100/6000 , 1.6% of 3v  at 100 feedrate correct ? And that's mean , i need to set my motors to reach maxim speed at 100 feedrate right?
The code are just for test to understand how all that work. That settings i found to be the best move on my motors ,
I keep digging .
Thank you Art ,

Hi:

  No, you dont need to adjust motors for that, you adjust feedrate. Here is my recommended process
once you have set the proper steps/unit for your motors.

Use Jog buttons and jog axis back and forth. Adjust the max velocity and max accel in the planner config
for that axis so the jog is as fast as you think the machine should do at 100% jog speed. Adjust the accel
so the Jog take off and stop are abrupt but not too abrupt. Make sure it is very quick to start and stop
and goes fast at 100%. Then slow jog to 20% and make sure its a nice jog motion.

Now, adjust the Jerk setting to 50,000. Make a GCode program of a large square that takes up most
of your table. Run the program and see how jerky it is. If each corner seems jerky, lower the Jerk
setting, if the corners seem too slow, raise the jerk limit. Find the jerk setting for which that
square runs fast and smooth. That should make the settings proper.

Now, set a feedrate of 100 in the Feedrate DRO. Run the program and watch the tool velocity DRO.
If the tool velocity hits 100 at any time, raise the feedrate to 200 and repeat. You will find eventually
a speed where the table will not hit the actual velocity any more. That is the point where the power will
no longer hit 100% if you go faster.

  For laser burning I use the Feedrate Override checkbox so that any feedrate command in the Gcode is ignored
in favor of the feedrate and Override slider % I have set. Each program is different so I run it without laser on to
see how fast it will go as an average. If I see the speed DRO is varying around 3000 or so, I set the feedrate
to 3000 and run the program with my preferred power selected on the Laser Power slider.

  Doing all this will give you maximum performance and is important if you intend to do 3d machining by laser
which is the most complex operation you can do in Auggie.

Art