I bought a bird feeder really hard to load with seeds. 

It is kinf of a mix: spoon + slide. It can help to load seeds in tight spaced bird feeder (and any other kind of bulk materials) into a container.

Best to print it vertically (only 15cm, can go on a small printer like Prusa Mini) but horizontally is much faster.

Designed in tinkercad - nice to start after 15 years from this level, like getting back on my forgotten studies.