I've cut a lot of 3mm basswood on my last laser machine (Ortur LM 3).  I had zero flare up or fire issues cutting.  I'm guessing the air assist helped quite a bit with keeping the flames away, however, the F1U doesn't have air assist blowing directly between the laser and material to minimize the flare ups.  What are your recommendations to ensure a clean cut through the wood without it scorching or catching fire?  I used the recommended settings from xTool Library Reference, I did my test cuts and used those settings but I either get the occasional flare up or the laser doesn't cut all the way through.  This is especially frustrating when cutting smaller shapes. 

My current method is to blow out the flame, like a candle, when see it, but that negates the usefulness of the green cover to protect eyes from the lasers.