Disc sander 150mm/6" with dust vents

Disc to build DIY disc sander. 150mm diameter for 150mm sanding discs. 14 x 10mm vent holes, 8 at the outer side and 6 at the inter side, angled at 45° for easy dust removal (for clockwise rotation). They should fit to the most of the sanding discs.

3 versions for download: M10x1.5 , M12x1.75 , M14x2
I also included thread test file, so you can see if it'll fit on your thread without printing and throwing away the whole thing if something goes bad.

14x2mm thread should to fit on angle gri