The tube is illuminated but I don't get clear firing to the piece. This is a rastering work and I get faint results and then it will be fine, then nothing. Tube changes from pink to solid line purple

If your laser machine needs to reflect off of three mirrors before it finally passes the focal lens, then I would recommend realigning the laser. You might also want to see if the nozzle is hot. If so, then the laser energy is hitting some of the nozzle body and not all of the laser energy is exiting the small aperture of the nozzle. To determine if this is the cause, remove the nozzle and try the operation again to see if you have better results. If the results are better with the nozzle off, then realign the mirrors. If you are still having difficulty getting the laser energy to exit the nozzle, increase the diameter of the nozzle aperture. If you are still having poor results, take a look at the focal lens and the mirrors for any debris. An unclean lens and mirrors are a common cause of poor lasing performance.