Silly question… How do you attach the bristles to the dust shoe? Do you just glue them together?
Slide bristles into the perineter slot on underside of dust skirt part. Then clip dust skirt onto dust shoe part. No glue needed.
Video clip @ https://zoomtube.com/@azab2c/make/v1e-lr4?s=Dust&v=2_0&t=12_46_30

