Scroll down for an important update!
So, my friend Jimmy and I saw an article on Slashdot about a "Solar Death Ray". This guy used 112 three inch mirrors. Not bad, but he mostly just melted crap.
I did some quick calculations and came to a few conclusions. First, to really burn shit you need about 300 mirrors. Second, the size of the mirrors is basically meaningless: 300 one inch mirrors will get a one inch spot just as hot as 300 three inch mirrors get a three inch spot, but need only one ninth the area.
I ordered about a thousand one inch mirror tiles on line, and Jimmy secured a 22x24 inch parabolic dish. (We both work for a company that writes middleware and applications for set top boxes. We're in the Denver area. You fill in the blanks.) I knew that we'd want to do a Mark II some day, and the mirror wasn't cheap, so we used drywall joint compound (a.k.a. "spackle"). I thought this would make it easy to remove the mirror later.
We rapidly assembled the S.D.R. MKI, with the help of J, a.k.a. Jay, a.k.a. J.W., a.k.a. John. We let the joint compound set (in the sun) for a duration of one beer. After a quick cleaning of the mirror, we drug 'er out in the sun for a test drive.
It's quite difficult to see, but this piece of paper is ablaze.
I later removed the mirror in anticipation of the Mark II. I soaked it in the tub for a couple of hours. It really wasn't much help. I counted the tiles I removed: 328.
Jimmy's dad had an old eight foot dish he wanted to get rid of anyway . . .
This is the entire ~1000 mirror set. We have a buddy, Pom, who does stained glass. Our plan is to cut a bunch of one inch tiles out of Goodwill/garage sale mirror. We haven't gotten our act together though.
(How can a handsome devil like me be single?!)
The focus really isn't nearly as good as the Mark I. On the other hand, since it has three times the mirror it was still good enough to light a 2x4!
You can't see the flames, but this 2x4 was on fire.
UPDATE: We have just received a plano-concave lens that should allow us to create a true "ray" or beam. Testing should begin in August.
UPDATE TO THE UPDATE: The lens worked, like, not at all. Obviously I am no master of Optics.
Coming Soon!
I make a t-shirt every day. Sometimes they're funny. Get the t-shirt feed.
One of my current projects is the Free
Curriculum Project. It's slow going, but I have high hopes.
The Free Software Foundation is doing very
important work for the future of computing and Freedom.
The JPFO is a fantastic organization.
Please check them out. They want me to link to them with the phrase
Jewish Firearms
for some
reason.
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me.
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What's up with those Amazon links?
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2003–2006 Peter Hutnick. All rights reserved.
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