The Light Sharpener

Intro Build Foil Mirror Burn Epilogue FAQ
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23 FAQ

More gluing. It was a lot easier to work towards the edge. When the dish surface was almost horizontal, I didn't have to worry about the tiles sliding around as much.

Sometimes I would change positions to feel the heat of a dozen suns being reflected onto my shirt and face. It was an invisible hazard, startling enough to keep my guard up.

Whenever the full sun was on the dish, I was tempted to stop and conduct a test.

Here is a photo of one test, the black coffee can full of water. It took me a while to realize this was actually a lame test, because the can was 9 feet in the air, and I couldn't see into it.

It also turned out to be a dangerous test.

Although I used an iron wire loop to keep the can on the pole, I used mere masking tape to keep the wire loop at the end of the pole. When the can and water got hot enough, the tape melted away. With no tape on top, the wire loop was untethered, and slid down the pole towards me. I dropped the pole in time, but it was scary, resulting in a big steamy splash of boiling water spraying up towards me and through the dish.

A photo of the back of the dish. 80% complete.

Tilted east, gluing more mirrors into place.

The dish was significantly heavier than when I had started. It was becoming very difficult to manipulate the orientation of the dish by myself.

On a trip to Home Depot to buy more tubes of Liquid Nails, I visited the welding supply corral and picked up some welding goggles.

These things are awesome. Forget Bono and forget his big sunglasses. Super dark welding glasses are what the kids are rocking these days.

On tiptoe, stretching to glue mirrors to every spot on the dish.

Occasionally, a mirror square with wet glue would break loose and tumble down the face of the dish, smearing adhesive across the fronts of a bunch of mirrors. Luckily, that only happened a few times.

With the last full sunlight of the weekend, I conducted another test.

These large sheets of 1/8" bark peel away from one of the trees in our yard. It was very dry wood, perfect for converting light into heat.

The hot spot is tough to reach, which is fortunate from a safety point-of-view, and it usually takes a little time to manuover the target into the brightest spot.

That bright spot was actually going to be difficult to photograph.

Here is the video.

The bark starts smoking almost immediately and is obviously well on its way to a flaming death in a few seconds.

I was thrilled. This was going to be everything I had hoped for, and probably more dangerous than I had anticipated.

Please continue reading page 15 of the Light Sharpener.

Intro Build Foil Mirror Burn Epilogue FAQ
1 2 3 4 5 6 7 8 9 10 11 12 13 14

15 16 17 18 19 20 21 22

23 FAQ

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July 17th, 2007.   Terms and Conditions  Copyright 2007