Review, Mods and use of my cheap ($325 shipped) Laser

[Scottl]

I'm fascinated by your experience and the possibility of an affordable laser cutter.  I find it interesting that the unit seems to take raster graphics files rather than vector like DXF and SVG.  If I had the space, I think this would be a lot of fun to work with.   It would be an invaluable modelling tool.

[rodsup9000]

  I find it interesting that the unit seems to take raster graphics files rather than vector like DXF and SVG.   
It would be an invaluable modelling tool.

 The software is the weakest part of these lasers, but like they say "you get what you pay for". When you buy a top on the line laser, you're paying for their great software too. I haven't tried any rastering yet, but will try it sometime.

 To me, it's was a no brainier to get one. When I started adding up all the structures I'll be needing for the RR, it'll pay for itself easily.     

[Chris333]

How fine can you focus the laser? Meaning what is the thinnest line you can cut.

[rodsup9000]

How fine can you focus the laser? Meaning what is the thinnest line you can cut.

 I'm guessing about .003" when cutting paper. So it is fine enough to do most anything you need it to do.

[Chris333]

Guess what I really mean is if you were cutting .015" thick laserboard and drew window muntins .015" wide would they end up destroyed? Some lasers cut a nice fine line other dig a trench. Some I've seen can hold a straight line and look like they wiggle.

[rodsup9000]

After some playing, I got these. I ended up drawing the outside frames 1.2mm wide and the mullions 1mm wide. The frame measured .030 wide and the mullions are .018". Overall it measures .517" X 268".
 I used some .012" poster board to cut these out.

 

[rodsup9000]

  OK, Getting back to the subject.

 Open Inkscape and click on "file",  click on "open".






 Find the file you want and click on it, and a new "Inkscape" window will open with your drawing in it.











  Go to file again (in the new window with your drawing in it) and go down and click on "Document Properties"
It will open on the right side and have this window.








Change to measurements to "mm" (or "in" for imperial) instead of "px"  in both places.








 
  Put you "box" size in the "custom size" box and you'll have something like this. If you don't have the "handles" around your box, click on the arrow in the upper left of the left tool bar and draw a box around it.










 using the handles, move your box to line up the the inkscape box. Zoom in on the corners and make sure they are aligned like this.



   





  Zoom back out and select the whole box again. Open "object" in the toolbar and click on "fill and Stroke".
 Open the "stroke style" and change it to "mm" and width to "0.02" and hit "enter". The drawing will almost disappear.








 Unselect by clicking the mouse somewhere on the screen. Go back to "document properties" and uncheck the box "show page border". Select each line of your box and "delete" them separately. Reselect the "show page border"




 If you imported your drawing in "imperial", you need to change the "custom size" box on the 'document" page to "mm" and remember those numbers, write them down so you'll have them.


 Open "file" again and select "save as" and in that window, go to bottom to "save as type" and select "emf"
Your drawing name and size should already be the the "file name" line.   "Save" it in your "Inkscape to Laser DRW" folder.








 Open "Laser DRW" and in the upper right corner, open "Laser Out Layout". Put your metric numbers in and click "OK"








  Go to "file' again and to "open". In that window find your file and open.




 




    And it is ready to cut. Click on the blue round icon with a flash of yellow, and the cutting window opens. Most of the stuff I've been cutting at 10 to 12 mm/s.










 
 



  Now if you get one of these, I hope I've saved you some of the grief I've went through the last 2 months.

[peteski]

I have some questions:

It seems that the machine has that very precise current adjustment knob. Is that controlling the laser's power output?  Does that mean that you cannot modulate the power to the laser from the drawing (for scoring/engraving and for rastering)?

I realize that validity of this question depends on the answer for the previous question. You mention that the software accepts raster (bitmap) files like PNG.  Are those used for engraving or are those used for actual cuts too?

I also don't get the metric/imperial thing.  A the size of the drawn vectors does not change with the measurement system - only the rulers do.  A 1" long vector will always be 24.5mm long and vice versa.  I'm surprised that the software makes a distinction.

[rodsup9000]

 From what I learned from videos and reading on the net, this laser doesn't raster very well and it will not raster and cut in one operation. I'm guessing the cheap interface board will not adjust the laser power while it running, it either on or it is off. The reason for the new pot, is to be able to finely adjust the laser power to do etchings for siding and such and it works very well.

 
 As far as the metric-imperial goes, again it was I've read or heard in the videos. I haven't tried anything other than this way.


 Here is some etching for siding I've done. The top is 1mm, or about 6 1/2 scale inches, (about .040") next is 1.5mm (.059") and the bottom is 2mm (.079)

[wazzou]

It looks to me like the board spacing is not consistent but wider/narrower on every other one.
This is more apparent on the larger spaced siding but is still evident on the others. 
That might be something that you need to compensate for in your drawings as you learn the ins and outs of the machine.

[peteski]

It looks to me like the board spacing is not consistent but wider/narrower on every other one.
This is more apparent on the larger spaced siding but is still evident on the others. 
That might be something that you need to compensate for in your drawings as you learn the ins and outs of the machine.

It might be slop in the mechanical parts.

Rod,
What about the PNG (bitmaps) files?  How it the laser software supposed to handle that type of file?

[rodsup9000]

It looks to me like the board spacing is not consistent but wider/narrower on every other one.
This is more apparent on the larger spaced siding but is still evident on the others. 
That might be something that you need to compensate for in your drawings as you learn the ins and outs of the machine.

 It appears that way and probably the cutting compensation on one side of the drawn line. I'll have to play with it and see if I can get it better.

Rod,
What about the PNG (bitmaps) files?  How it the laser software supposed to handle that type of file?

 




 I don't know and when I have time to play with it, I'll load a png into it and let you know.

[rodsup9000]

    So you don't get the charring on your finish side, face it down. In some cases, you may have to select the "mirror" selection in the laser software to get your cuts to come out right.







 

[rodsup9000]

Rod,
What about the PNG (bitmaps) files?  How it the laser software supposed to handle that type of file?

 Pete,

 Here is a "png" file loaded into the laser software. The grid lines are 1mm and you can see that the windows is a lot smaller than drew them. I drew each frame 7.5 X 14mm.

 I hope this answers your question.

[peteski]

 Pete,

 Here is a "png" file loaded into the laser software. The grid lines are 1mm and you can see that the windows is a lot smaller than drew them. I drew each frame 7.5 X 14mm.

 I hope this answers your question.

Interesting . . .

I don't own a laser cutter (but I know enough about them to be semi-dangerous).    In order to move the laser in the XY directions it needs vector-based instructions. It seems that the laser cutter software auto-traces the bitmaps (like that PNG) to create vectors.  The size of your artwork will then most likely depend on the dpi resolution of the bitmap file.   I also suspect that the software will only deal with bitmap files which contains line-art (black/white with no gray shades or colors).