I have recently purchased the 14W Jtech laser and the air assist upgrade. I am looking for some suggestions for the best air pump to use with it. Any suggestions would be greatly appreciated.
Most of the Chinese lasers use a simple aquarium air pump. https://amzn.to/3RAkRrm
If you have a shop air compressor, you could run an air line to your Jtech. Mount a pressure regulator by the machine so you can easily adjust airflow - less air for engraving, more for cutting.
You can likely do fine with the same ones the dedicated diode machines use such as the Dewallie or XTool ones. They come with variable controls on them.