On this date in 1834 Sandpaper was patented by Isaac Fischer Jr, Springfield, Vermont. 10 facts about sandpaper:
Sandpaper was around long before this, of course. The first recorded instance of sandpaper was in 13th-century China.
Not only that, but there’s evidence that the engineers who built The Pyramids used it, too.
Even before this, prehistoric people knew about abrasive action. They would sharpen their tools and weapons by rubbing them together.
Early sandpaper was made from crushed shells, seeds and Fish scales from Sharks and Coelacanth. Later on, sand and glass were used. Today it’s likely to be aluminium oxide or silicon carbide.
These abrasive items were stuck to parchment using natural gum. Today, the backing may be Paper, cloth, fibre or rubber.
The coarseness or fineness of sandpaper is known as its grit. The larger the number the finer the grit. The European measurement system is known as FEPA (Federation of European Producers of Abrasives).
A 1775 instruction for making sandpaper reads “To polish wood – Take brown paper, make it wet with glue, then scatter fine sand thereon, through a hair sifter – Sandpaper is equal to fish skins.”
The stuff that gets shaved off by sanding is called swarf. Some sandpapers have gaps between the grit particles which catch and hold the swarf so the item you’re sanding doesn’t get clogged up with it.
As well as grit size, another thing to take into account when selecting sandpaper is friability. This means the tendency of the grit material to break when exposed to heat and pressure. This is actually a good thing, as it creates new edges on the paper, so it lasts longer.
It’s also known as coated abrasive or emery paper.
Beta
(Combat Team Series #2)
Steff was abducted by an evil alien race, the Orbs, at fourteen. Used as a weapon for years, he eventually escapes, but his problems are just beginning. How does a man support himself when his only work experience is a paper round and using an Orb bio-integrated gun?
Warlord is an alien soldier who knows little but war. When the centuries-old conflict which ravaged his planet ends, he seeks out another world where his skills are still relevant. There are always wars on Earth, it seems. However, none of Earth's powerful armies want him.
Natalie has always wanted to visit England and sees a chance to do so while using her martial arts skills, but there are sacrifices she must make in order to fulfil her dream.
Maggie resorted to crime to fund her sister's medical care. She uses her genetic variant abilities to gain access to the rooms of wealthy hotel guests. The Ballards look like rich pickings, but they are not what they seem. When Maggie targets them, little does she know that she is walking into a trap.
Hotel owner Hamilton Lonsdale puts together a combat team to pit against those of other multi-millionaires. He recruits Warlord, Natalie, Maggie and Steff along with a trained gorilla, a probability-altering alien, a stockbroker whose work of art proved to be much more than he'd bargained for, a marketing officer who can create psionic forcefields, a teleporting member of the landed gentry, and a socially awkward fixer. This is Combat Team Beta.
Steff never talks about his time with the Orbs, until he finds a woman who lived through it, too. Steff believes he has finally found happiness, but it is destined to be short-lived. He is left with an unusual legacy which he and Team Beta struggle to comprehend; including why something out there seems determined to destroy it.
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