Air assist nozzle to suit NEJE A40640 laser module.

Problem: The available (metal, weighty) nozzle for this laser only suits an engraving focal-length: shorter.

Plus, as engraving doesn't really benefit from Air Assist like cutting does, I'm like..... 🤷‍♂️

Cutting focal length is best set longer, to give a more narrow beam profile.

Solution: When a long cutting focal-length of 46.4mm is set, this design extends the air outlet downwards to just 2mm above the work surface, optimising the airflow into the cutting groove/kerf.

Fun part: Being a performance engine builder by trade, you know that I just had to make sure that the air flows nicely.

No designs (including NEJE's own ones) I've seen for this module had nice flow characteristics, and most involved some work or expense to produce or buy. I had to fix this issue 😇

Aside from the four screws that came with the laser module, nothing but 4mm O.D. tubing and an (aquarium) air pump is required for use.

No adapter is required for 4mm air tubing as one is built in, just press it in for a neat fit.

Feel free to adapt the interesting bits to fit other laser modules.

Alternatively you can ask me nicely to adapt it for you :)