360° View - Scythe Zipang 2 Heatsink Information on Frostytech's test methodology is available here.
The 140mm fan is held in place on the Scythe Zipang 2 with a pair of wire clips. The fan spins at 1000RPM, and is powered by a standard 3-pin PWM fan header. With the fan removed we can see the large footprint of the aluminum fins (145x121mm) and the six separate rows formed by the heatpipes. Each bare aluminum fin measures 0.3mm thick and is spaced ~1.75mm apart.
The Zipang 2 heatsink stands 105mm tall and at the top about 140mm wide. The six 6mm diameter copper heatpipes are soldered to an extruded nickel-plated aluminum base cap which also doubles as the platform for CPU sockets to mount into. A benefit of the top-down design is that air is exhaust towards adjacent motherboard components. The bulk of the Zipang 2 heatsink is elevated 45mm above the CPU.
The nickel plated copper base plate on the Scythe Zipang 2 heatsink is 2mm thick and soldered to all six heat pipes. The base plate is mirror smooth and flat in both axis. Useable surface area measures 52x52mm.

Base Finish and Flatness

Flipping a heatsink over to inspect the business end is often a simple indicator of overall cooler quality. More practically speaking, a heatsink is in many ways only as effective as the contact it makes with the processor - the flatter and smoother the better. Base finish is one of the criteria that Frostytech measure in the course of evaluating heatsinks, and it involves two distinct aspects. Surface Finish is the first; this is calculated with the aid of Surface Roughness Comparator that has a cross section of common machine surface finishes and their numerical surface roughness equivalents in microinches. The second is Surface Flatness. This is tested with an engineers straight edge or proven flat surface, in two axis.

The base of the Scythe Zipang 2 heatsink has been stamped from a polished sheet of 2mm thick copper, and nickel plated. The base is smooth, with a surface roughness of ~8 microinches or better. It is flat in both axis.

Next up, sound measurements to determine how loud the Zipang 2 heatsink is when running at stock fan speeds.