While drilling some holes in concrete recently, I needed to extract the resulting dust from the holes and found that my vacuum cleaner was doing a poor job of it. 3D printing to the rescue! I designed and printed this attachment out and stuck it down the holes; et voila, no more concrete dust in the holes and my expansion bolts could be hammered in.
Inner diameter of the attachment is ~31.xmm, to slip over a 31mm vacuum cleaner end. No idea if this is standard or not, this is the diameter mine has.
The tip is ~9mm diameter and ~70mm long, slips comfortably into 10mm holes and bigger.
Best printed with a less rigid material to avoid cracking, I used PETG.
The author marked this model as their own original creation.