The Light Sharpener

Intro Build Foil Mirror Burn Epilogue FAQ
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There were a lot of pieces to this project which I hadn't yet located. This steel pole, once part of the stand for a basketball hoop, was lying discarded on the side of the road by the SMUD building in Sacramento. 

On the off chance it would fit the bracket, I scooped it up and brought it home. Four inches. The diameter was perfect!

I sawed it in half and drilled some holes to attach supports. I wanted to add three legs, to make a giant tripod. This would be a more temporary structure than a pole mounted in concrete.

Can you spot my error in the drilled holes? I wanted to run three bolts through the pole, but I drilled them at the same height, where the bolts would run into each other inside.

These had to be redrilled.

I used three 8-foot 2x4s as the legs to the tripod.

Attaching the legs.

Before I got any further on the giant light sharpener, our family visited Merced, where I had some sun-tracking practice with the tiny parabola on the bottom of a can of Coke.

Fire with Coke can and toothpaste

Richard and I got our target sticks to smoke, but they did not catch fire. If this tiny, less-than-mirror polished parabola could blacken wood, imagine what a dish with 5,200 times that much surface area could do.


When the tripod was finished, and some willing friends were over for dinner, we had a go at mounting the reconstructed dish.

First we had to maneuver the dish out to the yard. It wasn't that heavy, but huge, so that when it was vertical, its center of gravity was high in the air.

Cleverly, we waited until it was night, so that the sun would not be able to see what we were up to.

It didn't work. The satellite mount was flopping around, refusing to line up with the pole.

At the same time, it became apparent that the tripod was not sturdy enough. It needed to be actually  anchored, not just sitting on the ground.

We gave up for the evening. We had been so close, but it was probably better to wait until we could mount it safely.


Please continue reading page 5 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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May 23rd, 2007.   Terms and Conditions  Copyright 2007