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Fresnel lens

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  1. #1
    Hurrikane started this thread.
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    Fresnel lens

    Anybody using a Fresnel lens burner on metals?



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    auminer's Avatar
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    My wife saw a youtube video about them and specifically forbade me from constructing one.

    But..... that said..... she doesn't go in the garage much...
    Out of clutter, find simplicity. --Albert Einstein

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  4. #3
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    Quote Originally Posted by Hurrikane View Post
    Anybody using a Fresnel lens burner on metals?
    Please explain. I have a friend who is looking for one, but I don't understand the use for it.

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    travistemple202020's Avatar
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    not on metals but great for solar bbqs and hot water heaters camping or for boiling fresh water depends on the set up but upwards of 3000 degrees can do alot but never seen it in person melting down stuff but the idea is there i will have to look at the youtube videos and see it

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    Here's one use for it.

    I can think of a few serious uses as well. Gold melts at 1850 degree's F so it would be a great fuel saver for people who refine it from electronics scrap. Lead melt at 621.5 F so it could be useful for molding it. Also solder melts a much lower temperatures then both of those so I bet it could be used to depopulate a circuit board really quickly although the fumes and the bright light might be a problem. Maybe it would be ok if you wore sunglasses and a Full-Face Respirator.
    Last edited by Evan; 06-08-2014 at 06:38 PM. Reason: Spelling error

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  8. #6
    Hurrikane started this thread.
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    I've been thinking about doing some casting or just plain old melting and I really don't want to pay for fuel or have a big bonfire going. I built a frame for a Fresnel lens and am ready to go. Of course now the forecast is for cloudy days for the next week. I'm thinking that unless I do just a handful of material at a time the lens couldn't do it since you have to really focus the light to a small point. I guess that I'll have to build an array of them to cover a larger area. Ok people in Pittsburgh, put out your old rear projection tvs for trash tonight!

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    Hurrikane started this thread.
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    Quote Originally Posted by mthomasdev View Post
    Please explain. I have a friend who is looking for one, but I don't understand the use for it.
    Fresnel lens is basically a 3'x5' magnifying glass that can focus sunlight and achieve awesome(dangerous!) temperatures

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    Nerdmatt's Avatar
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    Fresnel lens

    Oh man. I just saw a projection TV in a dumpster the other day. To think, I could have been melting all kinds of stuff this past weekend

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    From what I've read there are two types of these lenses. Spot and linear. The spot lens is suppose to be the better, hotter lens. I removed one from a TV last summer but it turned out to be a linear lens and while I was able to melt plastic and burn wood it would not get really hot like a spot lens. There are plenty of youtube videos of people doing some really cool things with these lenses......and then there are the others...... Hold my beer and watch this!

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  13. #10
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    Apparently not all Fresnel Lens are created equal.

    I'm still on the look out for one. Maybe I'll get lucky and get a spot lens.

    Edit: Oh, jimicrk already said it. Sorry about that jimicrk.
    Last edited by Evan; 06-11-2014 at 12:11 AM.

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  15. #11
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    Also, If you get lucky and get a spot lens you might want to consider selling it on ebay after you're done playing with it.
    Last edited by Evan; 06-10-2014 at 11:50 PM.

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    Thanks for the tip on spot lenses. I was wondering why my lenses from old school overhead projectors weren't producing the desired effect.

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    Hey Evan
    The video you posted was the one I got my info from. From what I remember he has several videos demonstrating different lenses and how to make frames/stands for them. If you get one be careful how you carry it around. Wouldn't want to get the focal point in the wrong area. I remember the guy in the video saying something about it cutting a hotdog in half. Please be careful.

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