Hi Steve,
Excellent work with the laser building and beam alignment / setup video etc.
If I may be so bold as to make a suggestion, there is just one additional test that you perhaps may want to add to your alignment video – that the laser beam exits the nozzle at 90 degrees to the work table in both planes.
This, to a large extent, is determined by the position at which the beam hits the final mirror and it is easily checked by placing a piece of acrylic on it’s side on the work table in line with the X axis and firing the laser into it then checking that the resultant cut / hole is in fact square (and repeated again for the Y axis plane).
If this aspect is not set correctly then any thicker parts cut will not have vertical sides so IMO it is an important part of the alignment process.
Keep up the laser work and I look forward to seeing some more pictures / postings of the things that you make with it.
Tweakie.