Important: Make sure to download the latest files here, I am no longer uploading to Thingiverse: https://www.printables.com/model/164510-coffee-cold-brew-filter-funnel-for-pet-bottles

I AM STILL IMPROVING THIS, FILES ARE SUBJECT TO CHANGE!

I love cold brew coffee, for that reason I like to do big badges and keep the finished coffee in PET bottles. Cold brew coffee needs to be filtered, fo that reason I was looking for coffee funnels to hold the filter.

I couldn't find one which fitted all my needs, so I came up with my own.

Features V2:

• Compatible with common coffee filters (i.e. 1x4).
• Built-in PCO1881 thread for PET bottle.
• Built-in air vent to allow air escaping from the bottle while filtering.
• Special spacers to improve filter flow.
• Built-in insulation based on infill and air.
• No o-ring or tight seal required due to built-in bottle funnel.
• Designed specifically for 3D printing.

Features V3:

• All Features of V2.
• Re-designed air-vent so that it becomes an auto-stop once liquid level in bottle reaches bottom of funnel (UNTESTED!).

Features V4:

• Much bigger but less spacers for improved flow. Target is to filter as quickly as possible, this is for cold coffee which has been soacking before.
• Bigger air vent.
• Don't expect auto stop to work!

Features V5 (RECOMMENDED):

• Improved spacers in center for better flow.
• Adjusted angles and surface on bottom for better printing.
• Improved air vent (might not be needed due to big spacers at all).

Thanks to @terahurts for the thread definition!
https://www.thingiverse.com/thing:2693686