I like eating sunflower seed in my house, but I always run in to the problem of where to spit the shells. I decided to take it upon myself to design this tray. It has a big dish to hold old seeds and a small dish on top to hold new seeds. I recommend you use supports on the small dish and you can scale it to the size you like. I ended up liking around 35% scale. 

P.S. If you like my work check out more here! https://www.printables.com/@ATrain08_611047

Bambu lab A1

.4mm nozzle 

USE SUPPORTS!!