We demonstrate that the so-called pancake bounce of millimetric water droplets on surfaces patterned
with hydrophobic posts (Liu et al 2014 Nat. Phys. 10 [http://https://doi.org/10.1038/nphys2980] 515
) can be reproduced on larger scales. In our experiment, a bed of nails plays the role of the
structured surface and a water balloon models the water droplet. The macroscopic version largely
reproduces the features of the microscopic experiment, including the Weber number dependence and the
reduced contact time for pancake bouncing. The scalability of the experiment confirms the mechanisms
of pancake bouncing, and allows us to measure the force exerted on the surface during the bounce.
The experiment is simple and inexpensive and is an example where front-line research is accessible
to student projects.