The Prism Sharpener
iPhoneOgraphy – 28 Jul 2016 (Day 210/366)
A pencil sharpener (also referred to in Ireland as a parer or topper) is a device for sharpening a pencil’s writing point by shaving away its worn surface. Pencil sharpeners may be operated manually or by an electric motor.
Before the development of dedicated pencil sharpeners, a pencil was sharpened by whittling it with a knife. Pencil sharpeners made this task much easier and gave a more uniform result. Some specialized types of pencils, such as carpenter’s pencils are still usually sharpened with a knife, due to their flat shape, though since the 2000s a fixed-blade device with a rotatable collar has become available.
French mathematician Bernard Lassimonne applied for the first patent (French patent #2444) on pencil sharpeners in 1828, but it was not until 1847 that the pencil sharpener in its recognisable modern form was invented by fellow Frenchman Thierry des Estivaux. The first American pencil sharpener was patented by Walter K. Foster of Bangor, Maine in 1855. Electric pencil sharpeners for offices have been made since at least 1917.
They now come in a wide array of colors and shapes. It is common for traditional sharpeners to have a case around them to collect the shavings. It can be removed for emptying the shavings into a compost bin.
In May 2011, tourism officials in Logan, Ohio put on display, in its regional welcome center, hundreds of pencil sharpeners which had been collected by Rev. Paul Johnson, an Ohio minister who died in 2010. Johnson, a World War II veteran, had kept his collection of more than 3,400 sharpeners in a small shed, outside his home in Carbon Hill in southeast Ohio. He had started collecting after his wife gave him a few pencil sharpeners as a gift in the late 1980s. He kept them organized into categories, including cats, Christmas, and Disneyland. The oldest was 105 years old.
So-called “prism” sharpeners, also called “manual” or “pocket” sharpeners in the United States, have no moving parts and are typically the smallest and cheapest commonly used “pencil sharpener” on the market. The most simple common variety is a small and rectangular prism or block, only about 1 × 5/8 × 7/16 inch (2.5 × 1.7 × 1.1 cm) in size. The block-shaped sharpener consists of a combined point-shaping cone that is aligned to the cylindrical pencil alignment guide hole, into which the pencil is inserted. A sharp blade is mounted so that its sharp edge just enters the shaping cone. The pencil is inserted into the sharpener and rotated while the sharpener is held motionless. The body of the sharpener is often contoured, ridged or grooved to make the small block easier to firmly grip.
The blade inside the sharpener shaves the wood and graphite tip of the pencil, while the shavings emerge through a slot along the blade edge. It is important that the cylindrical alignment hole closely fit the diameter of the pencil to keep the pencil from wobbling; causing stepped or lurching cut-depths and point breakage. Another important feature is a larger clearance hole at the end of the cone allowing sections of the pencil lead which break away to be removed with only minor inconvenience. Prism sharpeners can be bare or enclosed in a container to collect the shavings. Enclosed sharpeners can be harder to clear in the event of a blockage. The base of such a sharpener is typically made of aluminium or hard plastic.
Moderate care is needed to not break the tip of the pencil being sharpened, losing the result of work immediately. However, because pencils may have different standard diameters in different nations, imported sharpeners may have non-standard-sized alignment guide-holes, — if it’s too-small the pencil cannot be inserted, while too-big (or missing,) and the tip of the pencil constantly breaks off,— making sharpening attempts futile. A few prism sharpeners are hand-cranked, as in the photo above. Prism sharpeners may be right- or left-handed, requiring clockwise or counter-clockwise rotation of the pencil being sharpened.
Posted on July 28, 2016, in iPhoneOgraphy 366, Photography and tagged #iphone6plus, #iphoneography366, #photography, pencilsharpener, photooftheday, prismsharpener. Bookmark the permalink. 2 Comments.