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Follow Twitter Instagram Facebook. How does an eraser work? What is graphite? Who invented the eraser? Tags: See All Tags carbon , eraser , friction , graphite , lead , paper , pencil. Not quite… now where did I put that eraser? Wonder What's Next? Try It Out Erasers help us correct our mistakes, but did you realize they can also be used to make all sorts of interesting crafts?
Take a look at the following art projects, and choose one or more to try: When you're finished, email or send us a letter with a picture of your eraser art project! Did you get it? Test your knowledge. Wonder Words graphite logical scientific lead mineral carbon softener abrasive Take the Wonder Word Challenge. Join the Discussion. Calvin Nov 14, Nov 15, Thanks so much!
But with eraser, the graphite comes out clean. Erasers are nothing but polymerized carbon, it is synthetic rubber. When eraser is used over pencil marks, the graphite stick out from the paper fabric and strick to erasers, and it appears the pencil marks are removed, while they are just transferring into the rubber from paper fabric.
The erasing mechanism of erasers is based on the principle of friction. When the eraser is being rubbed against the paper, the heat generated cause the rubber sticky and that way it becomes more suitbale for graphite to adhere than in paper.
Erasers are mostly made up of synthetic rubber, with vegetable oil used as softner and some sulphur to make it long last. More expensive erasers are made up of vinyl, plastics or gum liked materials. The first commericial eraser was invented by Edward Nairne in for an invention competition.
He accidentialy picked rubber instead of breadcums to erase and turn out rubber could wipe out pencil marks better than the soaked breadcums used in those days to erase pencil marks.
You are commenting using your WordPress. At this point, the rubber is cured under pressure and elevated temperature. Afterward, the erasers are cut into the final shape or removed from the mold, ready to be used. For pencil erasers, cylindrical ribbons of rubber are cut into short pieces called plugs. The plugs are placed in a rotating hopper that lines the plugs up on a conveyer belt that carries them to be married up with a pencil. A band of metal called a ferrule is glued onto the end of the pencil where a recess has been cut, while at the same time a plunger presses an eraser plug into the ferrule.
When the glue dries, everything is bliss. Making your own erasers. Making your own rubber bands. Advanced Options. Safety Letters. Table of Contents. Today's Headlines. Editor's Page. ACS News. Encountering this situation more than a couple times over a week may cause the user to arrive at the ensuing question: Why are some erasers more effective at erasing pencil marks than those from other brands?
This article will attempt to address this question by analyzing the two most prevalent factors of eraser quality, namely material engineering and age. Before diving into the following analysis, we must provide a precise definition. First, what is an eraser? The definition of an eraser for the purpose of this analysis will be that of a stationery tool produced using rubber or vinyl for the application of removing marks of graphite from paper.
This definition therefore excludes kneaded erasers mouldable erasers used by artists and fibreglass erasers extremely durable erasers that can be used to erase scratches on cars. The first major factor is material engineering.
To understand why this is so important, one must consider the microscopic forces at play when an eraser rubs away graphite from paper.
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