Why Some Erasers Don’t Work (And How to Find One That Does)

I’m sure we can all recall this scenario: You’re sitting in school, taking a standardized test. You know the answer is B, but for some reason you just filled in the bubble for C with your trusty No. 2 pencil, nice and dark, just like the proctor told you to. Fortunately, your pencil has an eraser. You flip that bad boy around and start scrubbing – except instead of a nice, clean C bubble, as empty as the day it was printed, you have a smear of graphite across the page, infecting the questions above and below. You look up at the clock, aware that you’re wasting valuable time as you desperately scrub at your page. The mark gets lighter, but is it enough? How sensitive will the Scantron machine be? You move on in the interest of time, but you keep revisiting that faint grey smear, and keeping your fingers crossed you won’t make another mistake.

So, why do some erasers fail? When Edward Nairne, an engineer, invented the eraser in 1770 he used the rubber from trees for his device. This worked quite well, as the rubber possessed properties that were well-suited to erasing pencil marks from paper. The exact composition of today’s erasers seems to be a well-guarded secret that varies from company to company, but according to Wikipedia, “Typical erasers are made from synthetic rubber, but more expensive or specialized erasers are vinyl, plastic, or gum-like materials. Cheaper erasers can be made out of synthetic soy-based gum.” And, as is the case with anything, as the materials get cheaper, the quality of the product degrades.

Before you launch an expedition to hunt down vintage erasers, it’s also important to understand that erasers undergo an aging process and dry out, rendering them just as problematic as modern erasers made with polymers and plastics. Even if you did manage to find an eraser from the 1770s, it would be worse than useless by now. Think about the Pink Pearl erasers you had as a kid. The ones in your pencil case were soft and gave a little when squeezed between your fingers. They warmed the pad of your thumb when you rubbed it back and forth because it created friction. The half-used ones in the junk drawer at home that had been lying around for years were a different story. They were hard, they were super-smooth, and far from being successful erasers you could write with them in dark grey-tinged pink.

Fortunately, over the years our friends at Pink Pearl have begun using better materials. No eraser is free from aging, but they last longer than they used to, and still have the beveled edges for precision and control. Art erasers are also a safe bet if you want to avoid smudging, as they are specifically designed for maximum absorbency. If you go with a kneaded art eraser you’re in even more luck – they are pliable so you won’t risk ripping the page with exuberant erasing. Another really great eraser is the Faber-Castell Dust-Free Art Eraser, which doesn’t leave behind rubber shavings when you erase that need to be brushed off the page and can smudge things you don’t want getting erased. Instead, the “dust” created by these erasers rolls together for easy removal from the page. As an added bonus, they are PVC- and latex-free, which means they are environmentally friendly!

If you’d like to find out more about why erasers often fail at their job, I highly recommend this article from The Atlantic. What kind of eraser do you use, and how do you like it? Let us know in the comments.