Difference between revisions of "User:Asj/Notes about laser cutting solder stencils"

From Nottinghack Wiki
Jump to navigation Jump to search
 
(One intermediate revision by the same user not shown)
Line 1: Line 1:
 
Most pads are ok - perhaps a bit large.
 
Most pads are ok - perhaps a bit large.
  
Small pitch QFN packages are a problem. To do these,
+
* Change the pad clearance in Lightburn
 
+
** File -> Board Setup -> Solder Mask Paste
* For each QFN pad, downsize "solder paste absolute clearance" to -0.09 and produce solder mask svg
+
** "Solder paste absolute clearance" -> -0.09mm
 
* Configure Light burn to engrave at
 
* Configure Light burn to engrave at
** 100mm/s at 30%
+
** 100mm/s at 28%
 
** Line interval of 0.02mm
 
** Line interval of 0.02mm
  
It might also be a good idea to apply this globally since other pads also end up a bit large. This can be done:
+
I like to soak a piece of paper in water and put it below the mylar. This helps reduce burning and warping
 
 
* File -> Board Setup -> Solder Mask Paste
 
* "Solder paste absolute clearance" -> -0.09mm
 

Latest revision as of 21:29, 20 May 2024

Most pads are ok - perhaps a bit large.

  • Change the pad clearance in Lightburn
    • File -> Board Setup -> Solder Mask Paste
    • "Solder paste absolute clearance" -> -0.09mm
  • Configure Light burn to engrave at
    • 100mm/s at 28%
    • Line interval of 0.02mm

I like to soak a piece of paper in water and put it below the mylar. This helps reduce burning and warping