I cut some .125" and .25" acrylic and experienced short cracks (.o625" - .25" in length) on the edge of the acrylic that were cut. The occurance of the cracking appears to have been random as it did not consistently happen on every piece.
I know the cracking is the result thermal expansion/contraction of the material. However, what I don't know is the correct % power as well as the correct speed mm/sec that would eliminate the cracks. Also, is the setting of one (either power or speed) more effective in controlling the cracking than the other?
Chinese Laser 50W, Air assist 18 psi
Setting were as follows:
.25" acrylic Power 98% Speed 3mm/sec
.125" acrylic Power 60% Speed 10 mm/sec
Thank You,
Roger