Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:752129.

When food scraps pile up in the sink you need a way to push them into the garbage disposal safely, even when it's on. This "disposal plunger" will push the scraps in, but cannot be pushed all the way through the opening.

It will fit standard garbage disposal openings about 8.5 cm in diameter.
Height is approximately 13.5 cm.
UPDATE Feb 2016 Added v1.1 with smooth sides all the way around.

No supports needed. I like a shell of 2 mm for strength and waterproofing with about 15% infill.

My first design! :)