Volcano Eruption Toy

This is a toy model volcano. Put several spoonfuls of bicarbonate-of-soda into the cavity and screw in the plug. Mix vinegar with some red food colouring and use a syringe to squirt it in through the top.

The plug.oring.stl can accept a 2.5mm profile o-ring to help the seal. The plug.noring.stl will probably leak but it doesn't really matter because it all makes a bit of a mess anyway. Do it all in a tray or outside.