Here is my take on an effector for the Anycubic Predator running with Magballs.
The effector is designed to allow two 5015 radial fans pushing air directly towards the part, without any airflow directing mechanism.

I've milled the upper & lower plate from 5mm aluminium.

Used CAD models:

5015 fan: https://grabcad.com/library/radial-cooling-5015-fan-50mm-dc12v-1
4040 fan: https://grabcad.com/library/40mm-dc-fan-1
Threaded heatsink: https://grabcad.com/library/e3d-threaded-heatsink-1-75mm-with-nut-1
E3D v6: https://grabcad.com/library/e3d-v6-hotend-3
BLTouch: https://grabcad.com/library/bltouch-v3-1-2

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