2L soda bottle spill prevention base

I use soda and juice bottles as a cheap container for Kratky-style hydroponics. The problem with most of the soda bottles that I have is that they have a bumpy base that is narrower than the bottle width, and because the bumps are rounded, it makes the bottles much easier to knock over with a very slight tap, especially if they are placed on an uneven or sloped surface. This has happened enough times to bug me into designing a fix for the problem.

The bottle base helps to avoid spills and waste, or the annoying CO2 explosion that happens when you knock a soda bottle over.  It does this by giving a soda bottle a slightly flared base (and effectively a lower center of gravity if you add a little extra infil), providing added stability and making the bottle less likely to be tipped over if casually bumped. This would also be useful at a table or when placing a bottle on the ground, to avoid the usual spills that happen at a kids party or at a picnic.

I've created this model to be a tight fit for a standard 2L bottle. It prints without supports and should fit most FDM printer beds.

I hope that you find this useful.

EDIT

I added a vase mode model as well, just for those of you who like that sort of thing, and it prints a tiny bit faster and smoother than the hex patterned version does.

My vase mode settings use a 0.6mm line width, and you will want at least 7 layers to strengthen the base and prevent the bottom becoming slightly bowed. 

I used a 0.2mm layer height in the pictured vase mode print, and with the speckled filament and vertical lines, you can't really see the layer lines. What can I say, I have acquired enough vanity over the last couple of years to want a purely functional item to also look nice. ;-)