I built this dust collection system in my wood shop a while ago. I had always wanted a centralized system with separate lines running to all the machines.
I would have been better off using 6" pipes for the main stem but as mentioned in the video, I could not, due to the low headroom.
The fan is a beast, and I have later made a new Thien top hat separator that works fantastic.
I have posted some mages on my instagram page here: https://www.instagram.com/p/Bj2Yz_tgkvf/
The best part of the system is the automated dust collector start on the blast gates. This prevents ANY gates from being left open, and will always result in maximum airflow on the blast gate used.
The longest line has an airspeed of 33 meters/sec or approx 110 feet/sec, even with 4 sharp 90 degree bends
This is the video I made showing the different blast gate types I used, floorsweep and how I configured the system.