Uncle Mud Permaculture Technology Experiments 2019 Part 7 Making Buttered Toast with the Sun

Continued from Part 2 (Sort of) where we are trying to melt glass with the sun but we got hungry. A Fresnel lens from an old TV is more than enough to melt butter on toast in about two seconds, but will it be enough to melt glass? Paul wants to recycle glass on site to make cool stuff instead of driving it to the recycler two counties over, but I think we need a bigger lens. Fortunately Josiah has some more ideas for making a solar glass furnace. This is the kind of stuff we do at the Permies.com Appropriate Technology Course (now the Permaculture Technology Jamboree) at Paul Wheaton Labs in beautiful Montana. Stay tuned as we share more clips from previous years including the rocket heater we were able to cast a glass pendant in. Or even better, join us in Montana this summer.

The purposes of the PTJ are:
1) Participants gain hands-on practice in a fully outfitted homestead fabrication and repair shop with tools from welders to sawmills to excavators under the instruction of experienced teachers--think of it as a shop class for homesteaders.
2) The PTJ is a serious research & development forum for DIY low-impact technologies such as Rocket Mass Heaters, Thermal and Photovoltaic Solar, and Local Natural Materials Building. Participants help us push the envelope on what is possible with appropriate technology.

Click below to register or to learn more. Class sizes are limited.

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PDC: https://wheaton-labs.com/permaculture-design-course?f=51
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Both PDC & PTJ
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Mix and Match
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Second half of the PTJ: https://permies.com/jforum?module=paidTopic&action=buyWithPaypal&topic_id=86659&f=51
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Did you buy the Fresnel len? If so where can I get one? And how big was the lens?

Paul bough the Fresnel lens, but if you look on Craigslist you can find people giving away Projection TVs with these lenses.