5L glass jar lid for fermentation airlock

Disclaimer: Fermentation/Homebrewing can vary in legality from country to country. Check local laws before attempting to do so. Consume alcoholic beverages responsibly and only according to local laws. I will not be responsible for any illegal use or misuse of my prints. Print/use at your own risk/responsibility. 

Fermenters for homebrewing can be difficult or expensive to get. This print can be used to easily convert Bormioli Rocco "Fido" 5L glass jars into fermenters by fitting them with an airlock. Here in Europe, these glass jars are available in supermarkets and stores or online, and can be as cheap as €9,10 per piece. A fermentation grade airlock can easily be bought for about €1,10 per piece. The lid can be printed for about €1,20 in material cost, bringing the total fermenter to about €11,40, which is the cheapest setup for a complete fermenter I could find. Let's dive into it.

The lid replaces the standard glass lid that comes with the glass jar. it is designed to use the standard rubber gasket that comes with the jar. An airlock is still required for this print. 

How to print correctly: 

The lid: print in PLA, with at least 7 wall loops, bottom and top shell layers to ensure an airtight seal. Must be printed with good layer adhesion/flow settings. If the lid is not airtight, check these settings first. As for infill: 15% is more than enough to make a solid print. It is important to print the piece lying flat on the bed, upside down for best results. 

The sealing tube: print out of TPU A82, or any other very flexible material that can be used for gasket making. Print standing up, with a brim securing the piece for bed adhesion. Must also have good layer adhesion to ensure an airtight seal. 

How to assemble correctly: 

1) remove the glass lid by removing the metal ring that holds the lid, then gently opening the ring and taking the lid out.

2) prepare the printed lid by washing it thoroughly, then sanitize it. Insert the cleaned and sanitized sealing tube into the hole of the printed lid. Clean and sanitize the rubber gasket that comes with the jar, and put it on the sealing surface at the bottom of the printed lid

3) snap the metal ring around the printed lid, and gently reattach to the glass jar

4) Squeeze a cleaned and sanitized airlock into the hole with the inserted sealing tube and check if the seal is airtight.

All siphon-type airlocks I got have about 9,2mm diameter at the bottom end, and work great for this setup. 3-piece airlocks probably work just as well if the dimensions are correct. 

Have fun making beer, wine, cider or fermented foods using this setup!