Results 1 to 13 of 13

Fresnel lens

| Metal Casting
  1. #1
    Hurrikane started this thread.
    Hurrikane's Avatar
    SMF Badges of Honor


    Member since
    Jun 2011
    Location
    South Park,PA
    Posts
    172
    Thanks
    95
    Thanked 155 Times in 66 Posts

    Fresnel lens

    Anybody using a Fresnel lens burner on metals?



  2. #2
    auminer's Avatar
    SMF Badges of Honor



    Member since
    Nov 2012
    Location
    Allen, TX
    Posts
    1,233
    Thanks
    579
    Thanked 2,301 Times in 857 Posts
    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

  3. The Following 2 Users say Thank You for This Post by auminer:


  4. #3
    mthomasdev's Avatar
    SMF Badges of Honor


    Member since
    Apr 2012
    Location
    pittsfield, ma
    Posts
    1,300
    Thanks
    348
    Thanked 1,532 Times in 704 Posts
    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.

  5. #4
    travistemple202020's Avatar
    SMF Badges of Honor


    Member since
    Jul 2012
    Location
    ames iowa
    Posts
    1,326
    Thanks
    267
    Thanked 883 Times in 495 Posts
    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

  6. #5
    Evan's Avatar
    SMF Badges of Honor

    Member since
    Apr 2014
    Location
    San Jose, CA
    Posts
    87
    Thanks
    83
    Thanked 101 Times in 42 Posts
    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 05:38 PM. Reason: Spelling error

  7. The Following User Says Thank You to Evan for This Post:


  8. #6
    Hurrikane started this thread.
    Hurrikane's Avatar
    SMF Badges of Honor


    Member since
    Jun 2011
    Location
    South Park,PA
    Posts
    172
    Thanks
    95
    Thanked 155 Times in 66 Posts
    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!

  9. #7
    Hurrikane started this thread.
    Hurrikane's Avatar
    SMF Badges of Honor


    Member since
    Jun 2011
    Location
    South Park,PA
    Posts
    172
    Thanks
    95
    Thanked 155 Times in 66 Posts
    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

  10. #8
    Nerdmatt's Avatar
    SMF Badges of Honor

    Member since
    Jul 2012
    Location
    Ijamsville, MD
    Posts
    12
    Thanks
    1
    Thanked 9 Times in 6 Posts

    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

  11. #9
    jimicrk's Avatar
    SMF Badges of Honor


    Member since
    Sep 2013
    Location
    Tennessee
    Posts
    2,825
    Thanks
    2,917
    Thanked 4,838 Times in 1,877 Posts
    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!

  12. The Following User Says Thank You to jimicrk for This Post:


  13. #10
    Evan's Avatar
    SMF Badges of Honor

    Member since
    Apr 2014
    Location
    San Jose, CA
    Posts
    87
    Thanks
    83
    Thanked 101 Times in 42 Posts
    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; 06-10-2014 at 11:11 PM.

  14. The Following 3 Users say Thank You for This Post by Evan:


  15. #11
    Evan's Avatar
    SMF Badges of Honor

    Member since
    Apr 2014
    Location
    San Jose, CA
    Posts
    87
    Thanks
    83
    Thanked 101 Times in 42 Posts
    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 10:50 PM.

  16. #12
    SMF Badges of Honor

    Member since
    Oct 2012
    Location
    Alabama
    Posts
    764
    Thanks
    1,067
    Thanked 1,213 Times in 471 Posts
    Thanks for the tip on spot lenses. I was wondering why my lenses from old school overhead projectors weren't producing the desired effect.

  17. #13
    jimicrk's Avatar
    SMF Badges of Honor


    Member since
    Sep 2013
    Location
    Tennessee
    Posts
    2,825
    Thanks
    2,917
    Thanked 4,838 Times in 1,877 Posts
    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.

  18. The Following 2 Users say Thank You for This Post by jimicrk:



  19. Similar threads on the Scrap Metal Forum

    1. Reading heads, lens, eye thingy
      By scrappygirl in forum Computer Recycling
      Replies: 8
      Last Post: 05-17-2014, 05:03 PM

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

 
Browse the Most Recent Threads
On SMF In THIS CATEGORY.





OR

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

The Scrap Metal Forum

    The Scrap Metal Forum is the #1 scrap metal recycling community in the world. Here we talk about the scrap metal business, making money, where we connect with other scrappers, scrap yards and more.

SMF on Facebook and Twitter

Twitter Facebook