I've created an insert for food contasiners, holding the tons of yarn spindles. The design is for 'Lock & Lock 1.1l' container, but easily adjustable in the Fusion 360 file. Just enter the size and count of poles.

There's a small descent around the pole, as some spindlecores rise outside. If the box is closed everything keeps it place - even if you shake the box.

I uploaded two versions (3x5 and 4x6 poles) as seen in the pictures and the Fusion 360 file.

The container we used is “Lock & Lock 253843” (https://www.amazon.de//dp/B0000AN4CH)