SummaryThe normal distribution with two channels in each side, at one and two standard deviations out from the mean. Sorry for the crappy pictures, I am really bad at judging good lighting. My other recent file should give a good reference point: http://www.thingiverse.com/thing:1381014Print SettingsPrinter Brand: LulzBotPrinter: TAZ 4Rafts: Doesn't MatterSupports: NoResolution: .5mmInfill: UnsureNotes: Brim! Use a brim. Using Cura, I just selected the Brim checkbox from the simple printing settings. I think it's 5mm.Post-PrintingRemove BrimOnce the print is done, the brim will be attache to the edges and some will fill the channels. Using tweezers to peel it off is quite easy.How I Designed ThisStepsRemixed ayoung's "Normal distribution sliced to show "68-95-99.7 Rule"" model by removing the numbers and splitting the pieces before sticking them all together. I then took this piece and used it to cut out a section from a (roughly) circumscribed rectangular prism. I then used this cut out on another rectangular prism of the same size to get back to a (now much smoother) curve piece. Then, I made a small rectangular prism (the dimensions of which I forget) and copied it six times, then used it to slice the channels in the model for the markers (cut one body using another).