Effective Print Head Fan Cleaning

[AhnoldZ]

Except for perhaps this post:

Help with ideas on governing duct pressure

During Makerfaire I asked about this exact thing. The Purex filter provided was pulling ~117 CFM (it has a display that shows filter status and live CFM gauge) which then cause the Glowforge’s exhaust fan to free spin I’d guess 800~1000 RPM. I was told that was okay and not to worry. Which means they have protection diodes on leads to the fan (Or this protection is built-in the fan - I’d have to see if I can see what model fan they are using) to prevent backflow of current. (Maybe?)

There are many people who have external fans force the GF fans to spin. No one has had problems yet. Maybe doesn’t mean they won’t - but so far so good.