My recent contribution to the Make Magazine’s Blog includes our lab’s analysis of cautery pens. The Secret Life of Cautery Pens does a teardown of those handy, but pricey, surgical tools.

From Make

Soldering irons get hot. Light bulb filaments also get hot. Cautery pen filaments get so hot that they can cut through flesh effortlessly. Physicians routinely use them for small surgical procedures. Unlike a scalpel, a cautery pen uses the heat from the filament to both cut and seal bloodflow, which can minimize the risk of infection and post-op complications. They are available at most online medical suppliers for around $12 each.

[inside] I expected a transformer, some type of power converter, a super capacitor. Instead, $12 gets you the electronics complexity of a pocket flashlight. Maybe they weren’t so special after all?

Aah, the tips. Maybe the tips are in fact special, some sort of complex alloy that’s optimally designed to heat up using two AA batteries. That would justify the price, and why the manufacturers can rack up the cost of a reusable one to $24.

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