Heatsinks are great. Not only do they serve an important purpose in keeping our electronics cool and safe, but they’ve got that neat thing going on where they’re all spiky and springy. Have you ever stopped and wondered, though, how a heatsink is actually made? I never had, until today, but am now very glad I know.
Like, how do all those sharp fins come together? Are they stuck together at the bottom? Squished flat then cut out into shape, like shiny pasta? The answer is no, neither of those things. It is a process that is much more satisfying to watch.
This video, posted by a Korean account late last year (but shared this morning by rombik_su), shows the process called “skiving.” This is where a big chunk of copper is laid out and a machine, which is very wet, just slices away at it.
Every time it cuts it then gives the freshly-hewed piece a little nudge into a vertical position, and there you go. The main component of a heatsink, ready to cool.
As nice as this is to watch, it’s also kinda weird, since it’s a process that looks more like a Second World War production line than anything involved in creating modern consumer electronics. Turns out all that cutting has its advantages:
...the skiving process also increases the roughness of the fins. Unlike the underside of a heat sink, which needs to be smooth for maximum contact area with the heat source, the fins benefit from this roughness because it increases the fins’ surface area on which to dissipate heat into the air. The fins may be made much thinner and closer together than by extrusion or formed sheet processes, which can offer greater heat transfer in high-performance waterblocks for water cooling.
Because I’ve now spent my morning looking up other skiving videos on YouTube, I’ll leave you with a machine that cuts four heatsinks at once: