Most of the plans I saw online for a dust shoe for a CNC router involved some sort of skirt material to keep the chips from flying away. This works pretty good but blocks the view of the cutter. Using 3 pieces of 3/4 scrap, I made scoop that redirects the suction over the spindle/collet. When used with my Harbor Freight 2HP dust collector, the air velocity is great enough that 98% of the chips are captured.

The upper layer is sized to fit the spindle and a 4" dust fitting. The middle layer is open and acts as a tunnel to redirect the air from the dust side of the shoe to the spindle side and the lower level has an opening around the collect for the air. The upper and middle layer are glued together and the middle and lower layers are held together by 1/4" rare earth magnets.

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