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FrozenGate by Avery

Sun + Magnifying Glass = ?mw

[highlight][move]AWESOME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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Well that definitely was interesting...

I finally dug out my old screen and took the fresnel out of it, then rigged the fresnel only back into the frame. I took it out in the sun, and after finding just the right angle/focal point(not an easy task while freehandedly holding it), I managed to instantly ignite cardboard ;D. The best focal point I could get was about 25x25mm.

I tried a 2x4.. it only took about 5-6 seconds before I had a flame:)I couldn't manage to hold it steady for long though..

I hope to rig a nice solid frame/ mount to it, and see what kind of practical uses I can find for this setup:)

EDIT: For safety, anyone trying this will definitely need good eye protection... All I have is a couple pair of sunglasses doubled up, and I was still seeing spots for a couple minutes:(
 
This giant-fresnel fire starting stuff almost requires a video. I'm going to have to find somewhere to get one of these huge lenses. Jamil, did you just walk into a tv repair shop and ask for one, and they gave one to you? Thats pretty awesome! You should probably try to make some kind of frame to mount it in, then you could attach it to some kind of handle and walk around roasting entire anthills in one pass. 8-)
 
It is kind of tricky to get a huge lens like that in just the right position.. so frying anthills will require some finesse. Also the frame is definitely required, as the fresnel is flimsy, and needs to be flat to work correctly.

I'll try to post a video, if I can fin a suitable filter for my camera.. the spot these create is BRIGHT :o.
 
jdub said:
This giant-fresnel fire starting stuff almost requires a video. I'm going to have to find somewhere to get one of these huge lenses. Jamil, did you just walk into a tv repair shop and ask for one, and they gave one to you? Thats pretty awesome! You should probably try to make some kind of frame to mount it in, then you could attach it to some kind of handle and walk around roasting entire anthills in one pass. 8-)
Click to expand...
i called first and will make a frame
 
dude i cant believe you got that for free, wth!!

in argentina not even the air is free :P



oh, and how do you do that scrolling text (html cmd?)
 
Niko said:
dude i cant believe you got that for free, wth!!

in argentina not even the air is free :P



oh, and how do you do that scrolling text (html cmd?)
Click to expand...
yeah i never get anything for free except this and a laser from dave.
 
i got a reply."Dear Jamil

Thank you for your inquiry.
The 1040mm x 780mm size lens,the price is FOB Nanjing USD100/pc.
Please inform us your order quantity of the 1040x780 lens and your address include your telephone number. I could calculate the total price include the express charge for you.

Best Regards
Ms Sun"
i wonder why her name is ms sun
 
I want to try and get a fresnel lens now after reading this thread. I went to order that 13" fresnel lens from edmund optics, they are only $8, spent like $10 on some other things, but shipping to australia worked out well over $80! :o
 
I was in the dollar store and there they were ! Fresnel lenses 8.5 x 11 inches for 1$ each.
I got a fresnel 29 x 38 inches from a projection TV in the garbage at work. These lenses are worth the effort to look around for. (And I thought that my 4 inch lens was a good burner) In the photo, the dollar store fresnel in in its package, with a 40 inch metal ruler beside it, are leaning on the big fresnel from the garbage. Total cost for both - $1 .
 

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