First-Surface Drain

Summary This is a bulkhead fitting I designed to add drains to a series of buckets/troughs. It is designed to attach lengths of (garden) hose to the outlet barbs. . The drain can fit through a 3/4 to 1 inch hole through any flat container wall up to 1 inch thick. (Swimming pools, barrels, ponds, fish tanks, or whatever you've got.) . The drain is what I call "first surface" (more on that in the instructions tab) which basically means it looks interesting and is printable without additional supports. Instructions This model was successfully printed on Makerbot using PLA with 20% infill, 2 shells,, 0.30 layer height. . You'll need to cut the support fin(s) off the barbs with a razor blade and/or file after printing. (See photo.) . "First surface"? The original design was the obvious solution of a dome with holes in it. The hollow cavity inside led to printing problems and attempts at slicing were messy and cumbersome. Then I got the idea of using a set of vertical fins to prevent material from dropping down inside, and thus providing their own support. . The algorithm for this is pretty fun too. What I did was, knowing the maximum hole size I wanted (2mm), I determined that circumference=num_fins*(fin_width+min_hole). Therefore, I just back-calculated at what radius the gap would be too big and doubled the number of fins at that point. (Interesting geometry problem that makes an interesting design. What more does a nerd need, right?)