** update september 2016 **
added two V2 components, to accommodate the new Z plate
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This dust shoe does not go up and down with the router, so there's almost no friction on the brushes, they basically are only used the accommodate space for clamping.

In the video you see the fully printed version (I'm cutting the alu part). In the pictures you see the alu version with quick release.

The tube inlet is 40mm, the size of my "triton dust collection bucket" -

You can use the fully printed version, but the version with an aluminium mounting bar is much stiffer.
As you have a shapeoko to cut the aluminium I would advice you make the aluminium version. You need 15x15mm aluminium.

The aluminium version is meant to be used with a quick release for easy adjustment of the height. You get these types of quick release at the bike store, I used one meant to clamp the saddle.
I used brushes meant to mount on a letterbox, cut to size, they snap fit, I actually had to hammer them in...