Creating a Water-Powered Hammer Using Stone Age Tools

iStock // vuk8691
iStock // vuk8691

A "Monjolo" is a water-powered hammer made from a log and some sticks. It relies on flowing water from a stream to do its work.

In the video below, the anonymous laborer who goes by Primitive Technology on YouTube creates his own Monjolo from scratch. It's effectively a hollowed-out log placed in the path of a stream, supported by a structure of skinny beams. As the log fills up with water, it rises, then the water drains out the back and it comes crashing down again. When it crashes down, that's an opportunity for a hammer head on the end to do something useful—like crushing charcoal or grain.

The creator of Primitive Technology writes:

This is the first machine I’ve built using primitive technology that produces work without human effort. Falling water replaces human calories to perform a repetitive task. A permanent set up usually has a shed protecting the hammer and materials from the weather while the trough end sits outside under the spout. This type of hammer is used to pulverise grain into flour and I thought I might use one to mill dry cassava chips into flour when the garden matures. ...

Like all the Primitive Technology videos, this is done entirely without spoken or written language, and it's DIY paradise. Tune in for a look into what one man alone in the bush can create:

The ChopBox Smart Cutting Board Has a Food Scale, Timer, and Knife Sharper Built Right Into It

ChopBox
ChopBox

When it comes to furnishing your kitchen with all of the appliances necessary to cook night in and night out, you’ll probably find yourself running out of counter space in a hurry. The ChopBox, which is available on Indiegogo and dubs itself “The World’s First Smart Cutting Board,” looks to fix that by cramming a bunch of kitchen necessities right into one cutting board.

In addition to giving you a knife-resistant bamboo surface to slice and dice on, the ChopBox features a built-in digital scale that weighs up to 6.6 pounds of food, a nine-hour kitchen timer, and two knife sharpeners. It also sports a groove on its surface to catch any liquid runoff that may be produced by the food and has a second pull-out cutting board that doubles as a serving tray.

There’s a 254nm UVC light featured on the board, which the company says “is guaranteed to kill 99.99% of germs and bacteria" after a minute of exposure. If you’re more of a traditionalist when it comes to cleanliness, the ChopBox is completely waterproof (but not dishwasher-safe) so you can wash and scrub to your heart’s content without worry. 

According to the company, a single one-hour charge will give you 30 days of battery life, and can be recharged through a Micro USB port.

The ChopBox reached its $10,000 crowdfunding goal just 10 minutes after launching its campaign, but you can still contribute at different tiers. Once it’s officially released, the ChopBox will retail for $200, but you can get one for $100 if you pledge now. You can purchase the ChopBox on Indiegogo here.

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How the Trapper Keeper Trapped the Hearts of '80s and '90s Kids

Courtesy of Cinzia Reale-Castello
Courtesy of Cinzia Reale-Castello

No matter when or where you grew up, back-to-school shopping typically revolved around two things: clothing and school supplies. And if you’re an adult of a certain age, you probably had a Trapper Keeper on that latter list of must-buy items.

Like the stickers, skins, and cases that adorn your smartphones and laptops today, Trapper Keepers were a way for kids to express their individual personalities. The three-ring binders dominated classrooms in the '80s and '90s, and featured a vast array of designs—from colorful Lisa Frank illustrations to photos of cool cars and popular celebrities—that allowed kids to customize their organizational tools. 

In this episode of "Throwback," we're ripping open the Velcro cover and digging into the history of the Trapper Keeper. You can watch the full episode below.

Be sure to head here and subscribe so you don't miss an episode of "Throwback," where we explore the fascinating stories behind some of the greatest toys and trends from your childhood.