http://www.soliforum.com/topic/13229/lc … d-printer/

1. Make sure any images are thoroughly Black and white, it won't even read dark grey as to be engraved

2. If you plan to use the additional cut feature of it .
  2a. Make sure whatever shape on the outside is atleast 2 pixels wide and makes a complete shape around the image. Aka contagious shape for the outside, since the cut only "cuts" the outside of the shape
  2b. Make sure no stray pixels. I had a lil test file where I made a file to engrave a pattern inside a circle (which was just the pattern I wanted engrave with a circle around it to cut). I had ONE pixel outside the outer circle and it threw it off till I removed the stray pixel.
   2c. Make sure atleast a pixel or two of whitespace around your image
   2D. Seems to only take BMP files

3. Sometimes if you switch from the other options to B+W+Cut the red line indicating where the cut goes, does not show visible till you hit the generate the gcode button. Seems to be a minor glitch, but nothing major.

4. Seems the best way to control where the cut/engrave will be done on the bed of the 3D printer is to just surround your image with whitespace. I.e I made a 6 inch by 6 inch square (size of my print bed) and plopped by image in the center and saved it as a BMP file. I also have done a 12 inch by 12 inch BMP sample image, and LaserEtch has an option under "basics" named "Half Pixel Height" I checked with allowed me more resolution...maybe other ways too that I have not explored.

I have been working on a profile for LaserEtch, but of course I can't test it but I can add things to added to the gcode automatically  at the beggining(and end) etc via the software like the M302 (allow cold extrusion)...maybe I won't need that gcode, but I added it so hopefully the code wouldn’t stop on an error.

Form what I understand from the L-Cheapo Wiki "Feed rate is used to control cutting; some values for materials follow. - Paper: 12mm/sec - Acrylic: 2mm/sec - Leather: 5mm/sec ". While LaserEtch does not have a direct setting for Feed Rate, I assume something that can be done in GCode additions. Which I am guessing is the GCode F2 would be for acrylic, Paper F12, Leather F5. All seem so low, but since the laser needs to go slow, that makes sense depending on what you are cuttingI guess you can only go so slow, but that is probably why they say you need multiple passes for some materials , I am not quite sure yet if I I can just enter F12 as a gcode line, or if it needs additional parameters.

after numerous test to try to find a way to reverse the Z movement... i switched to a simple hardware solution :

i reverse all the wire that goes to the Z motor (4 wires...  1 2 3 4 , change to 4 3 2 1 ) AND i removed the Z switch and put it on a bit of wood  glued to the bottom of the SD2 under the bed (the height size of the wood will be the new ZERO. something like 70/80mm tall will be ok)..  so now the bed goes UP instead of going down

also, you need to change the PRINT AREA HEIGHT in the printer setting/printer shape of repetier-host (from something like 150, to something like 50 - it will be the max thickness of the material that you can cut and will be the max height that the bed can move up from the new ZERO))

you will change the Z offset in Printer setting/General to something that with be the THRU thickness of the material you will put on the bed surface...and this height will be where you will focus the laser -

with that, you need to adjust the speed and some other parameters (size of the nozzle.. etc etc)

i can give you my slicer profil to help as a start place...

it's a raw hacking, but it works...  it's not a definitive modification of the printer so you can reverse it to a 3d printer if you want to

I loaded that Slic3R profile prevoiusly, but it does not address the -Z issue; I am hoping the L-Cheapo people have some sort of solution or maybe the previously mentioned software will work