At 100% scale each sugar bomb is 24.8mm tall, or the size of a very large Corn Pop.
These were designed for a 0.4mm diameter nozzle. The tail section has a constant width of 0.8mm FYI.
Cereal should be light weight, so consider keeping that infill as sparse as you can. Maybe 10% or less. These are technically small enough for 0% infill if you want to try it.
I've provided .3mf files with multiple instances of the same sugar bomb to keep the file size down, yet allow for up to 120 sugar bombs on one print bed of a Mk3-Mk4 printer without too much issue.
(On the flip side, an .stl file with 120 sugar bombs is considerably large and may slow down some computers, so I left it out)
I will include an .stl file of a single sugar bomb for those who prefer it.
The cereal box in the photos was made by this artist if you want to go check them out:
Splemsby
