Characterizing The Laser Cutter

Here are my main takeaways from the group assignment for this week. Here is the group documentation.

Kerf

Kerf is the material that is obliterated when the laser vector cuts. We measured kerf by cutting out 1in X 1in squares and measuring their dimensions. Here are my major takeaways:

  • kerf is different for different places in the material - more energy from the laser is applied to the top of the material, removing more of it
  • the difference in kerf for cardboard and wood is within ~0.05in, though the average kerf for cardboard is higher than that for wood

Dithering

Dithering is an error diffusion algorithm that works to diffuse errors in shading and colors. We tested five different dithering algorithms on cardboard, plywood, and acryllic by printing out the same image on all three. Here are my major takeaways:

  • Stucki and Jarvis dithering appear the most consistent with the original image
  • Floyd-Steinberg dithering has more intense and contrasting colors
  • Standard dithering has deeper and more well-defined shadows and darker areas
  • Bayer dithering looks more saturated than the other dithering types

Power

Power is the amount of energy in the laser. We vector cut 10 different lines with different power settings. Here are my major takeaways:

  • lower power makes the cuts smaller and doesn't go all the way through the material
  • too much power creates a lot of soot and a larger hole

Speed

Speed is how fast the laser cutter moves. We vector cut 10 different lines with different speeds. Here are my major takeaways:

  • similar to the inverse of power -- lower speed makes larger cuts with more soot -- probably because more energy spent in each place
  • higher speeds create thinner lines that may not cut all the way through

Frequency

Frequency is the amount of laser pulses over a given distance. We vector cut 10 different lines with different frequences. Here are my major takeaways:

  • out of all the settings, frequency has the least obvious impact on line weight and debris
  • higher frequency create slightly thicker lines with a little more soot

Joint Clearance

Joint Clearance is the amount off from the thickness of a material that a joint is. We tested three different cardboard press-fit joints with different joint clearances. Here are my major takeaways:

  • too large of a joint clearance allows the joint to fall out
  • even without chamfers, a carboard press-fit joint is fairly effective with no joint clearance
  • a negative joint clearance combined with chamfers can make a very sturdy press-fit joint out of cardboard