CNC & Machining Education Workshop
Drilling Square and Hexagonal Holes

We have covered the process for drilling square holes (with rounded corners) using the Watts drill before, but in the intervening time some cool videos demonstrating the process have surfaced on YouTube, e.g. the one I’ve embedded, above, from user jacquesmaurel.

The Watts drill is based on the Reuleaux triangle, and this promotional video for the book How Round is Your Circle? (which we covered back in 2009) animates the principle nicely.

Turns out it’s also possible to drill hexagonal hole using a very similar tool based on the Reuleaux pentagon. The video immediately above, again from jacquesmaurel, shows a tool he describes as a “Vika attachment,” mounted in a lathe, boring an hexagonal hole in a piece of stock. The video below, part of the Wolfram Demonstrations Project, illustrates the process.

These Reuleaux-polygon based drilling and boring processes should not be confused with the very similar process of rotary broaching. [via Core77]

14 thoughts on “Drilling Square and Hexagonal Holes

  1. Am I the only one who thinks that this is at best some terrible editing, and at worst, just plain deceptive? The second to last video starts out with a hex shaped hole. The second video from the top isn’t doing any cutting because there are no metal shards. And both of them would have been 100% better is they showed us the bit coming out of the hole as opposed to cutting to another shot entirely. I’m not saying this technology doesn’t exist, but why do the example videos remind me of that terrible street magic show with david blaine.

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I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I am a long-time contributor to MAKE magazine and My work has also appeared in ReadyMade, c't – Magazin für Computertechnik, and The Wall Street Journal.

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