2 Liter Bottle Funnel Insert

thingiverse

Two-liter soft drink bottles in the US can be repurposed as funnels after emptying their contents. However, cutting off the bottom leaves behind very flimsy sides. To address this issue, I created a round insert designed to stiffen the cut-open end and reinforce the sides/opening of the bottle. This insert features a friction fit that may require slight adjustments based on potential differences in each bottle's dimensions. The original design for the ring was based on specifications provided for a standard 2-liter bottle with an outside diameter of 110 mm. Unfortunately, this measurement proved too large and needed to be revised. Further refinement led to a final dimension of 107.25 mm, which allows the ring to fit snugly inside the cut-off end of the bottle. If the model does not fit for you, scaling up or down by 0.5 to 1% may be necessary. A subtle 1 mm chamfer is incorporated into the part of the ring that inserts into the bottle, facilitating easy sliding on and off.