The Concrete Lathe Project

April 15, 2012 by kris de decker Filed Under: DIY, Lathes, Metalworking, Random

concrete lathe

“Metalworking lathes are necessary to the production of almost everything but are very expensive. In 1915, special lathes made from concrete were developed to quickly and cheaply produce millions of cannon shells needed for World War I.

Lucien Yeomans, the inventor, won the nation’s highest engineering award for it but sadly the technique was almost forgotten after the war. We re-discovered it as a way to quickly make inexpensive but accurate machine tools for use in developing countries and in trade schools and shops everywhere.”

Pat Delany developed a metalworking lathe design that uses concrete parts cast in wooden molds to achieve high precision at a rock-bottom price of $150. Find the detailed building plans at Make Projects. Also check out Pat Delany’s low-cost DIY machine tools (such as a hand-powered drill and a treadle-powered generator), all built from recycled parts.

Velomobiling

March 26, 2012 by kris de decker Filed Under: Bicycles, Bikes, Pedal power, Recumbent tricycles, Travel, Tricycles, Trikes, Video

A fifteen minute ride in a velomobile. Previously: The velomobile: high-tech bike or low-tech car?

Open Source Energy Production: The Solar Fire P90

March 16, 2012 by kris de decker Filed Under: DIY, Energy, Solar

solar fire p90

Solar Fire is currently testing a larger version of its low-tech solar concentrator; the Solar Fire P90. Just like its smaller predecessor the Solar Fire P32 (which we covered before), the machine can produce heat, electricity and direct mechanical energy, making it suitable to manufacture almost anything on your roof or in the garden.

The Solar Fire P90 delivers up to 5 kW of electricity and 40 kW of thermal energy, is built using simple, abundant and non-toxic materials, and requires no foundation in the ground. The frame size is 11.5 x 11.5 metres and the machine requires an area of 16 x 16 metres for revolving.

Tracking is done by hand using a simple but ingenious system — one person can operate up to five of these solar concentrators at the same time. The Solar Fire P90 is an open source design, but it can also be bought for about $ 12,000, excluding transport costs.

A video of the tests can be found here. For more information on the workings and applications of these kinds of machines, see the article “The bright future of solar thermal powered factories“.

Picture: Solar Fire.

Dog Sulkies: Pet Powered Mobility

March 8, 2012 by kris de decker Filed Under: Animal power, Cargo, Dogs, Random, Travel

dog sulkies

Dog owners looking for a more sustainable means of personal transportation should not look any further: the dog sulky is the answer. Dog powered vehicles have been used for the transport of goods and passengers in some European countries during the nineteenth and early twentieth centuries. Compared to those vehicles, the modern dogcarts offered by ChaloSulky promise to deliver a much smoother ride. The carts benefit greatly from the use of bicycle wheels, suspension and brakes. Moreover, the dogs are not confined between two shafts. Instead, only one shaft goes over the animals’ back, making the vehicle lighter and giving the dogs more freedom of movement.

[Read more…]

Pottery Refrigerators

March 5, 2012 by kris de decker Filed Under: Food storage, Refrigeration

Zeer potNgo Practical Action is working with communities to make zeer pots – very clever fridges made using clay, water and sand. They consist of two earthenware pots of different sizes, placed one inside the other. The space between is filled with damp sand that’s kept moist by adding water, and the smaller pot is filled with food. The top is covered with a damp cloth, then as the water in the sand evaporates towards the outer surface of the larger pot, there’s a drop in temperature of several degrees. This keeps the contents of the smaller pot cool. A zeer pot can keep 10kg of food fresh for up to 20 days.

More low-tech refrigeration.

India’s Ancient Stepwell Architecture Cools Modern Building

February 28, 2012 by kris de decker Filed Under: Air conditioning, Architecture, Cooling, Pools, Water

“At the height of summer, in the sweltering industrial suburbs of Jaipur, Rajasthan in north-west India, where temperatures can hit 45C Pearl Academy of Fashion remains 20 degrees cooler inside than out, by drawing on Rajasthan’s ancient architecture. While the exterior appears very much in keeping with the trends of contemporary design, at the base of the building is a vast pool of water — a cooling concept taken directly from the stepwell structures developed locally over 1,500 years ago to provide refuge from the desert heat.”

Read more: Ancient ‘air-conditioning’ cools building sustainably.