Overhead drill dust catcher

I made a "cone of shame" for my drill, the kind that you would use to keep your dog from licking his surgical stitches. Except that this is just to catch the dust from overhead drilling. There are several excellent dust catchers on Printables for drilling on the wall; this is for when you have to drill into the ceiling.

I have to install several ceiling mounted smoke alarms, which will produce a bunch of dust that will fall down. This double cone mounts on my drill to catch the dust. Just have to remember to keep the drill pointed up until I find a trash can. 

Even though I'm not very good at it I created an scad version, so you can adjust the parameters as you need. $d_ is the diameter of the drill, which is the inner diameter of the printed part. $ht_top is the height of the top cone, above the intersecting plane. $fa and $fs have been set for a pretty smooth surface. I've shown both versions on my slicer build plate. Anyone who is good with scad is invited to critique my code.

Then it occurred to me that a square top version would be better, because it would allow getting next to a wall or in a corner. Available in .3mf, or in .scad to customize.