The breaking bad coffee maker actually makes terrible coffee,
If you are interested in a coffee extraction that is truly sophisticated and can be DIY produced via a sep funnel, a Büchner flask and some knowledge of percolation- look into Yama style slow drip coffee.
It’s a form of cold brew that is made via percolation- that is- a Chinese torture style drop by drop saturation of the mark and yields a completely different product from traditional cold brews
Yama cold brew is like champagne while traditional steeped cold brews are more like port or sherry.
Recreating gales rig will likely not yield anything at all that could be considered coffee