On special request from my dear mother I designed a quick fill funnel. My mother makes her own kombucha tea and she does this in 5 litre glass jars. These are fairly heavy so when the time comes to bottle it she would like to transfer it into bottles as fast as possible. Most ends on funnels are fairly small and don't provide a way to let the air out when using it. So I designed the following funnel so that it just fits the bottle and that it has an unrestricted way for the air to escape when you pour the kombucha in.
The files if you want to print our own can be found on thingiverse.
George Timmermans, Research Toolmaker, Software Engineer and Tinkerer