Commercial airlocks are not expensive by any means, but if you are like me and don't live close to a home brew store, you are on your own. Ebay sellers want ~$2 plus whatever gouged shipping charges they feel like putting on top of that. I have a simple solution for you, you can make your own super cheap one for less than $2 and maybe even free if you have all the stuff lying around!
I list 2 different methods, one is the bare minimum way (~36 cents plus some spare things you probably have lying around) and the other is the recommended way (a little under $2). I only have pictures for the recommended way but the diagram I use can be altered to work for either method.
Step 1: Materials
- Plastic tubing
- Jar (clear is best)
- Something to punch a hole with
+ Hot glue gun
+ 1 Nylon barb and matching nut (I got this from the hardware store, ~$1.25)
+ Plastic tubing (~ 2 feet, depending on where you will be placing your jar)
+ Jar (clear is still best)