Messages

281

General Mach Discussion / Previous Versions

« on: February 22, 2012, 02:01:43 PM »

I'm having some error message problems with Ver. 3.043.058 and Mach3 shuts down and want to send a report to MS.  I want to revert to Ver. 3.043.057 (need M10/M11 commands), but it does not show up on the FTP site.  In fact, lots of later development versions seem to not be there.

Am I missing something?

Regards All,
John Champlain
www.picengrave.com

282

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

« on: February 20, 2012, 01:03:34 PM »

OK, think now the original image will post  - got my fingers crossed 

Dan, I probably do misunderstand the way Art's plug-in works, but tried to base my explanation my personal trial and this:

"Shades are achieved within the Engraving plugin by varying the Pulse Repetition Frequency (not PWM) on the digital trigger output. A PRF of 100% would be equivalent to maximum power and a PRF of 0% would be equivalent to minimum power. In practice the Engraving plugin never gets anywhere near to a 100% PRF (see my pdf document for values related to feedrate http://www.machsupport.com/forum/index.php?action=dlattach;topic=12444.0;attach=26734 ) but manual control of the maximum tube current can, to a large extent, compensate for this.
The manual control of tube current can be adjusted at any time during operation to achieve the appropriate laser power for the job in hand. A multiturn potentiometer with calibrated dial is good because the adjustment is quite fine and the dial enables the correct settings to be recorded so that they can easily be used again at a future date for a similar job.
The Engraving plugin, as mentioned earlier, controls the laser’s output power by adjusting the PRF and this, in turn, is directionally proportional to federate and pixel value (high federate = high laser output power : low federate = low laser output power : no feed at all = laser off). It’s really just as simple as that.

I hope I have explained all your questions.

Tweakie."


At any rate, it did not work for me, hence my search for another way.

Regards,
John Champlain
www.picengrave.com
picengrave@verizon.net

283

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

« on: February 20, 2012, 12:49:28 PM »

Something ate the other two pics - trying again.

284

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

« on: February 20, 2012, 12:47:00 PM »

As examples, here are three pictures - original, grayscale, and Floyd-Steinberg dithered.  I hope this helps to clarify the process a little.

John Champlain
www.picengrave.com
picengrave@verizon.net

285

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

« on: February 20, 2012, 12:29:06 PM »

Thanks Tweakie,
I am close to a release version of PicDither, but as you know some other personal things slowed me up for a while, but I'm getting back up to speed now.  As always, your work is first-class and your pioneering work is much appreciated.  Please keep the examples coming.  Maybe someday my little laser diode will grow up into a full blown CO2 laser  

Dan, I can not use Art's plug-in as it does not work well with my lower powered, slower firing, 1 watt laser diode.  But if I understand correctly, Art's plugin varies the on/off cycle time of a laser based upon the gray value of an image pixel.  This means as a pixel goes from black towards white, the laser will fire a series of shorter bursts for each pixel to simulate a gray value.  Converting (dithering) an image changes all pixels of an image to either white (laser off) to black (laser on) according to a matrix formula, of which there are several.  This allows the laser to fire full power for each pixel that is black in a dithered image.  This is similar to the process that newsprint photos are printed (look closely at a newspaper or magazine with a magnifying glass to see the "dots" that make up an image).

My program will apply any of several different dithering matrix algorithms to an image to produce a 2-bit image suitable for impact or laser engraving.  I have not tested impact yet, but hope to do so soon.  Tweakiie has posted some great examples of of his impact work here on site.

Regards All,
John Champlain
www.picengrave.com
picengrave@verizon.net  

286

General Mach Discussion / Re: G31 Probe

« on: February 12, 2012, 04:35:09 PM »

Keith,
This is what I use.  Original version was in Digital Machinist Magazine - forgot the author's name.

' Version #1
PlateThickness = GetUserDRO(1151) 'Z-plate thickness DRO
If PlateThickness <=0 Then ' is plate thickness set?
Code "(Plate Thickness Not Set)"
Exit Sub
End If 
If GetOemLed (825)=0 Then 'Check to see if the probe is already grounded or faulty
DoOEMButton (1010) 'zero the Z axis so the probe move will start from here
Code "G4 P1" ' this delay gives me time to get from computer to hold probe in place
Code "G31 Z-1 F10" 'probing move, can set the feed rate here as well as how far to move
While IsMoving() 'wait while it happens
Wend
ZProbePos = GetVar(2002) 'get the axact point the probe was hit
Code "G0 Z" &ZProbePos 'go back to that point, always a very small amount of overrun
While IsMoving ()
Wend
Call SetDro (2, PlateThickness) 'set the Z axis DRO to whatever is set as plate thickness
Code "G4 P0.25" 'Pause for Dro to update.
Code "G0 Z0" 'put the Z retract height you want here
Code "(Z axis is now zeroed)" 'puts this message in the status bar
Else
Code "(Z-Plate is grounded, check connection and try again)" 'this goes in the status bar if aplicable
Exit Sub

End If

Hope this helps.
John Champlain
www.picengrave.com

287

General Mach Discussion / Re: Engraving stick fonts

« on: February 11, 2012, 08:51:46 AM »

Well, not knowing for sure exactly what you mean by "waver",  it could be CV action also 'contributing' to a shortening of some strokes.  It was affecting my text until I played with CV settings.  Sorry, not near my machine so can't check my settings just now.  Test in Exact Stop mode to see if it straightens out.

Regards,
John Champlain
www.picengrave.com

288

General Mach Discussion / Re: corners getting radiused at higher speed on plasma table

« on: January 30, 2012, 01:39:11 PM »

 

289

General Mach Discussion / Re: corners getting radiused at higher speed on plasma table

« on: January 30, 2012, 12:58:57 PM »

Ian,
Thanks much for the very informative post.  I'm adding you to my card list 

Regards,
John Champlain
www.picengrave.com

290

General Mach Discussion / Re: New to Mach3, would like someone to point me in the right direction

« on: January 28, 2012, 07:44:33 PM »

Well, you could look at the Nesting Wizard supplied with Mach3.  Might do what you need.  I use it.  Works great.

Regards,
John Champlain
www.picengrave.com