Wearing a cast is certainly a frustrating experience, but it doesn't compare to the terror some people feel when it's time for removal. High-power tools near a vulnerable area intimidate anyone; however, Steve Mould on YouTube shows us that plaster saws don't work the way our minds imagine…
Personally, I've worn enough casts to confirm two things: 1) Some people are terrified of the removal process, and 2) You never fully trust the person wielding the saw. Add to that multiple horror stories of injured patients because some intergalactic genius trusted their steady hand a bit too much and ended up causing cuts that required several stitches. A fundamental step to reduce that lingering fear is to understand how a plaster saw actually works, and Steve Mould teaches us the exact process with this video…
The Science Behind a Plaster Saw
Everything becomes clear when we watch the saw in slow motion: its blade isn't spinning but oscillating at high speed, with a travel that doesn't exceed three millimeters. In fact, slow motion is optional—a mark on the blade serves as a reference too.
The key is the elastic deformation limit of our skin. Steve demonstrates with two balloons—one half-inflated, the other fully inflated. The half-inflated balloon behaves similarly to our skin: its surface moves and stretches under the blade's teeth. The inflated balloon lacks that ability and bursts at the first sign of friction.
At the same time, Steve demonstrates why it's not a good idea to use rotary tools like a Dremel. Our skin's elastic deformation isn't broad enough to withstand the energy of a Dremel, and other oscillating tools could also be dangerous if they have too much travel or if they're sharp. Finally, Steve shows that there aren't major differences between traditional plaster of Paris and the newer fiberglass-and-resin 'casts,' except for a cleaner cut in the second case.
