Vector engraving lines is a faster process then raster engraving, so we decided to do a test on how far we could push the feedrate when raster engraving a Black & White ClipArt image.
In a previous test, we determined the Maximum feedrate the EmBlaser could run raster gcode was 171IPM (4343.4mm/min) when using a .006" (.1524mm) Pixel Resolution.
We edited this image in PicEdit Lite for the size, saved it, then re-oped it to Dither the image with the Threshold Algorithm to ensure it was pure Black & White.
http://etc.usf.edu/clipart/86200/86257/ ... erator.htm
In PicLaser Lite, we set the Feedrate at 170IPM (4318mm/min), Max power to "255" and min power to "0" and engraved at a 45D angle. The set feedrate in PicLaser Lite is not relative when using PicFRC and adding Feed Rate Change afterwards.
By using a Dithered image, there will only be a S power value of "255" in Black areas and S power value of "0" in white areas with no other power levels in-between. This is called TTL (pulsing) laser engraving.
We opened the file in PicFRC and set the feedrate at 170IPM (4218mm/min), Max power at "255" and Min power at "0" with a 60% Feed Rate Change. In the White areas it will run at 170IPM (4318mm/min) and Black areas it will slow to 68IPM (1727.2mm/min).
The engraving was 6.25" wide and 4.932" tall and took 1 hour 20 min to complete. This process does not replace vector engraving as it's still slower, but it will give better detail & results when using a Dithered line art or ClipArt image and raster engrave it instead.
This is the first time trying this and we could have lowered the percentage some more in PicFRC so it would have ran a little faster in the Black areas.