Our first group assignment was: characterize your lasercutter's focus, power, speed, rate, kerf, joint clearance and types
We focused the laser by using the little tool and raising the bed until the lip hit the edge of laser cutter head.
For kerf we decided on .254mm based on a measurement of the material blasted away after a cut was made.
Joint clearance was simply the thickness of the cardboard 4.4mm + the kerf
We made press-fit and chamfer joints using the value for thickness to make snug fits.
For cutting we found that 100% power and 10% speed worked well for the standard "cut all the way through" setting, but we also wanted to determine the settings for scoring, i.e. cutting through most of the cardboard, but not all the way through so it can bend and fold. We ran some tests at different power/speed combinations to determine this setting for the 60W laser cutter:
| Power (%) | Speed (%) | Result |
|---|---|---|
| 100 | 13 | Very bad, cuts all the way through |
| 100 | 14 | Very bad, cuts all the way through |
| 80 | 20 | Bad, sometimes cuts all the way through, sometimes doesn't |
| 70 | 20 | Bad, very floppy folds |
| 55 | 25 | Good, easy to bend & fold |
| 45 | 25 | OK, kind of difficult to bend & fold |