Siphoned Layers Published September 2, 2019 at 1233 × 1910 in 3D Printing a Better Black and Tan Part 2: A Testable Prototype ← Previous Next → Partial success! Guinness (upper) and Bass (lower) layers formed via siphoning. The second beer was poured into the reservoir just before the first beer finished, so a fair amount of mixing occurred. Some bass remained in the reservoir.