Filament spool end for laser cut 8mm board

This was made to counteract the large hole in laser cut cardboard spools for holding plastic filament. This Thing reduces the hole size from 54mm to 24mm (the size of the section broom handle that my spools sit on) and provides a more durable bearing surface than the 8mm card, which was a bicycle box in its previous life.

Although this Thing is functional and fit for purpose, I wasn't entirely pleased with the circles on this model, as Tinkercad composed them of a series short straight lines.