Messages

21

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 19, 2018, 08:41:42 AM »

 Yup, typical problem. Best to just keep playing with material and such to find one that gives a
good grey scale on your machine, then photos shoudl start to look better.

Art

22

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 19, 2018, 07:46:45 AM »

Dan:

>>There doesn't seem to be any laser control commands, just G1 moves side to side.

  Its because the Gcode loads an Augment file at the start and that sets photo mode.

   Thats standard GCode for Auggies Photo engraving setup. The laser in Auggie's photo
mode only turns on in G1 mode moves AND only when the x,y position is in the extents
of a loaded photo. This allows one to accelerate toward the photo with burning starting
automatically as the laser enters the photo and stopping as it leaves. This allows for constant speed
photo engraving which smooths out any aberrations caused by accel and decel of the laser head.
  Since power and speed are semi-linearly related in laser cnc, having a constant velocity can
help when burning a photo. Although in general use Auggie will vary the power as a linear function
of actual velocity, the correction is not quite linear enough on most lasers for photos, so for photos
we do this acceleration rejection method to make them clearer.

Art

23

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 18, 2018, 10:06:11 AM »

>>on G1 moves the laser turns ON and on G0 it turns OFF.

  Auggie works the same. It saves a lot of switching statements and I find it preferable
to other types of control statements. As your probably ocked into a set power range for a photo
unless you can set the power level range, you may want to experiment with various treatments to
the material to perhaps get a better range.

Art

24

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 18, 2018, 08:38:55 AM »

Nice photo Tweakie.

25

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 18, 2018, 08:38:00 AM »

Hi Dan:

 Variations caused by wood grain are usually desirable as they identify the wood its on. Your problem may be more
related to absorption profile. UV lasers dont work the best on organic matter. The higher the frequency
or shorter the wavelength of a laser the less it is used for organics, and more for marking metal.
  CO2 and Yag ( either end of the infra red spectrum) are easily absorbed by organic matter like wood ( or skin
or corneas) while UV  absorbs differently than the others. For example if you hit your
eye with a CO2, its probably fixable as the burn occurs on the outside of the eyeball, whereas UV will go
through the first layesr and damage the retina at the back of your eyeball, and may not be fixable.

   So while UV will burn wood, its a smaller portion of the energy that's doing the burning. Its why UV is used more for
engraving a photo on metal than wood, and you may find the photo looks better on an aluminum plate or metal
surface of some kind, though grey scale may suffer as that's a property of the surface material.

  UV lasers also suffer from optics, an LED isnt easy to focus to a tight focal spot, the optics are difficult
so the typical lower end laser dont have great optics on them usually. This can limit its ability to get sharp
results. You may want to try on a white painted surface and finding the power levels that best produce a
grey scale. Paint tends to darken on a more linear scale.

   If your using Auggie, in its config there is a setting of minimum power and max power. Setting that properly, by setting
minimum to the level at which you begin to see burn, and max to the power where its dark enough will allow Auggie
to create a grey scale that's best for that laser as it will scale power to between those two levels.

  I'm sure a UV can do photos, but I suspect you need to treat the wood with something that assists the absorption
like a resin or paint ( wood conditioner maybe), then using the proper power range should allow a grey scale.

  I don't use UV yet, I'm all CO2 here, so I'm no expert on such matters, but all this may give you some things
to consider. I'm just hooking up my third CO2 laser now ( I have a 10w and a 40w, I'm adding a 48w)
 and building a new cabinet for it, so Ill be playing more with photos myself in the future,
though I'm more interested in cutting paper with my new one, than burning it.
    

Art

26

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 14, 2018, 01:15:35 PM »

Hi Dan:

  I find its wood and focus. Being in focus sometimes hurts you, sometimes helps. Try just a bit off focus to try to
create a grey scale effect from power... In focus sometimes can just remove wood cleanly with no burn..

Art

27

Mach4 General Discussion / Re: Mach4 Printer Port Discussions

« on: January 13, 2018, 08:51:15 AM »

Hi:

  Checking the source I see its hardwired to .25 seconds. Probing wasnt used much in Darwins time.
Ive attached a build I just did today.  My development system has changed alot since last build of
darwin and I no longer run XP so I cant test this. Can you let us know if this plugin

a) works
b) fixes the probe to a faster stop.

Thanks,
Art

28

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 12, 2018, 08:17:50 AM »

Tweakie:

   I see Mach3 as the hobbyist package ( I use M3 on my workshop router still.), I have M4 setup for testing,
but I dont run it much as its pretty pure on its own, its a pro level no nonsense CNC controller.Doesnt need much
help from someone like myself.
     Auggie is for experimentation and easy access to hardware not typically supported
like a laser, and so will suit the very few of us who like to work at a lower level of access to hardware.
  Its from such things that idea get developed though, and it wouldn't surprise me if someday packages like
Mach4 support PWM as an output.  When it does its because of things like Auggie and persons like you who
play and do such nice work. I see the ESS has added PWM, so with the Pokeys and ESS now having a pwm option
it may just be a matter of time till the more pro end of software supports it, and thus more controllers. Its a circular
loop of chicken and egg.  The ability to control a PWM signal from the position within a data set virtual to the
tool location is something thats handy in a few area's, not just lasers.

{
( My suggestion for the archive..in case the M4 writers read this   )

  I think all CNC controllers should have some sort of command that attaches a datafile to a pwm signal with a
rectangular dimension settings. Like Attach( "Mydata.dat, XSize,YSize, BYTE_COLOR); The PWM would then reflect
at all G1 moves the value within that file (0-100%)  based on type of data,in this case 3 byte color data. 

}

  I always found if you offer it, people will adopt it if its a good idea. As you've mentioned before, the engraving plugin
at first was greeted with a yawn when I wrote it, but over time its been popular with a lot of people judging by the
size of this thread.

Art

29

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 11, 2018, 08:07:16 AM »

Tweaky:

  lol, you know, when I wrote Mach3, it was the result of wanting something personally to
engrave photos. The responce was so overwhelming I ended up making very few photos's over
the intervening years as Mach was built up. Ive learned to live vicariously through the
artistry of others.
 
  So it pleases me no end to see your success with it, your photos are definitely better than any
Ive output.

  Keep up the great photo work, nice to see impact is coming along and that Auggie can at
least get you started with experimenting in it..

Art

 

30

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: January 10, 2018, 07:43:52 AM »

 
Tweaky:

 >>Because I am happy that the following software is not in any way in competition with Mach

 Theres never any problem if you wish to discuss competition to Mach3, While Im proud to have written
it I have no proprietary interest in Mach3, so its just one of many options available these days. On this board nothing
is really off topic for discussion.  Im always interested in hearing the various options available to folks.


Art