Since I built my large 50L coolerbox mash tun, I have often struggled to make beers in less than 20L batches, especially when they are not strong, this is because my mash tun doesn’t work very well unless I use about 7KG of grain. But from time to time I want to mash a smaller amount, for brewing an experimental beer, or perhaps a starter beer in 5-10L batches. Here is my quick and dirty solution. It cost very little to make, and it took me about 30 minutes.
I simply cut a small hole in a 8 or 10L food grade bucket which previously held bird seed. I attached a ball valve tap to a brass threaded compression fitting, with a washer on the inside. I stuck a short length of copper pipe hammered flat at one end, with slots cut along its length (it was a bit from an old mash tun). I cut and wrapped a foam mat around the outside and attached it with silver gaffer tape, this is for insulation. I reckon it will be good to mash anything from 1-3KG. Now to mini-mash a starter beer!