IKEA 365 fermenter

Description 

The airlock consists of two small chambers that are filled with water. As the sourdough ferments and produces CO₂, the gas passes through the water chambers and bubbles out. This creates a simple water barrier between the sourdough and the outside environment.

Facts

• Two water-filled chambers

• Simple design inspired by laboratory-style airlocks

• Only 2 printable parts: airlock body + nut

• Compact size: approximately 60 × 40 × 15 mm

• Prints very easily and quickly

• My version was printed in black PLA

• Simple assembly using either a 16 mm O-ring or hot glue

• The “floating” water level indicator does not actually float, as PLA has a higher density than water. I also wasn't able to design a hollow structure inside the small cavity. I decided to leave the indicator in the design anyway, as it is still useful for checking the water level. Simply grab the top corner of the indicator and pull it out to check the height of the water level.

Printing

I printed the airlock on an Adventurer 4 using PLA.

• 0.4 mm nozzle

• 0.2 mm layer height

• 5 inner and outer walls

• 5 top and bottom layers (almost solid)

The model consists of two parts:

• Airlock

• Nut

I wouldn't go higher on the layer height in order to ensure the lock remains watertight.

How to use

Drill a 16 mm hole through the lid.
Add a small amount of hot glue to the lock, or place a 16 mm O-ring around the mounting stud.
Screw the nut tightly onto the stud on the bottom side of the lid.
I clean the lock every 2–3 weeks using a 50% alcohol/water mixture to ensure that no mold builds up inside.

How to create sourdough inside the IKEA 365

Day 1

• 100 g whole wheat flour

• 50–80 g lukewarm water

Day 2

Stir the mixture 2–3 times throughout the day.

Day 5 and following

Add 50 g fresh whole wheat flour and 50 g lukewarm water.
Let it rest for 3–6 days.
Again, add 50 g fresh whole wheat flour and 50 g lukewarm water.
Check if the dough rises to 2× or 3× its original volume within a few hours after adding the fresh flour.
If yes, the starter is ready, and you can use a portion of it for your bread.
Otherwise, discard 100–150 g of the starter and repeat the feeding/discarding process every 4–7 days.