// Simple cover for a mosquito bacillus thuringiensis trap // UV radiation may slowly kill the bt... so use an opaque container // and cover it with a lid with a smaller hole in it. Might help // control evaporation as well, and it helps not having open // containers of water around (probably don't want wild animals // drinking a soup of decaying bug larvaue). // The trap itself is just water, orange blossom water (which contains // skatole... I think) as an attractant, and some bt granules or // dunks. $fa = 0.1; $fs = 0.5; module mosquito_honeypot_lid (lid_diameter = 50, lid_depth = 15, hole_width = 20, wall_thickness = 1, bottom_thickness = 2) { total_h = lid_depth + bottom_thickness; difference () { cylinder (d = lid_diameter + wall_thickness*2, h = total_h, center = true); translate ([0, 0, bottom_thickness/2 + 1/2]) #cylinder (d = lid_diameter, h = lid_depth+1, center = true); translate ([0, 0, -lid_depth/2]) cube ([hole_width, hole_width, bottom_thickness*4], center = true); } } // wall thickness calculation halves value //mosquito_honeypot_lid (lid_diameter=72.5, lid_depth=18, wall_thickness=4, bottom_thickness=2); mosquito_honeypot_lid (lid_diameter=71, lid_depth=25, wall_thickness=2, bottom_thickness=2, hole_width=25);