Used to they sold a huge fresnel lens in Edmund Scientific. It was like 3x4 feet or something. They said it would make temps of thousands of degrees from the sun, and would melt asphalt in seconds. <img src="/ubbthreads/images/graemlins/ooo.gif" alt="" /> I always wanted one when I was a kid. <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> I think they quit selling them. However, I’ve had an idea for several years but never tried. Those older big-screen TVs have a huge fresnel lens for the “screen”. That might work for some cool experiments. Those TVs are only good for 10 years or less before they go bad. I’ve seen a lot of them given away free on freecycle etc. Usually say “needs work” or something. You could pick one up free and keep the lens. I have a 8.5 x 11” fresnel lens. When I was in AZ, I tried using it as a woodburner on some old logs to write my name. Worked great. I only had to keep in in place for a second or two before moving it. Just move really slow and burn right along. <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> Imagine what fun you could have with a giant lens. Think how quick you could boil water to sterilize it for instance. All without a flame.

interesting..
yes the sun is a huge source of untapped energy.. free for the taking..
if only humans could learn to use sunlight the way plants do.. it would be amazing.

to be a plant...with arms and legs....and other stuff.

LOL.. very poetic.. that post is.. and stuff.

That's to funny

Andy that is awesome! Thanks! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" /> I want one. <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />

Cool stuff, they did one of theese on Mythbusters and lit a boat on fire on the water a couple hundred feet away . Nothi'n beats a death ray.

Any plant but brocolli. My hair looks funny enough the way it is now.

It sure would be a cool project. Or an awesome entry for a science fair!

Well, sorta. If the boat moved at all it would work. They finally decided that it was a busted myth.

they bust every myth. let em stand on a mora stuck in a tree.

if they bust that one i'm writing a letter
voicing my displeasure
which extends beyond measure
since there's no myth that can weather
the two of them together.
fortunate, however,
that i could braid a tether
that would hold like red facial hair leather
as they are tarred and feathered.
that makes it better.

Archimedes designed a sun weapon to defeat the enemy's of Greece back in the day.
Still kicks butt!. Solar power is hot!

Peace.