We have a 50w fiber laser and have an issue with consistency of depth while engraving bold text or specific large solid sections of graphics.
When lasering at 225 deg. depth is greater at the beginning then gradually a little shallower.
I have tried various angles, speeds and line resolutions... even a small fan to cool.
It seems running faster 350 speed and loosening up the resolution to .05 from .01 helps.
I an not experiencing this issue with other metals.
Is the aluminum heating up and as a result not uniformly atomizing.... I say that because on a 10 loop run, the first 5 loops have a bright white laser response..... but later in loop 8,9 and 10, there is less intense light.
To work around the issue I cheat and ad a couple of small metal pieces to shield certain spots from becoming too deep.
Thanks
John