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Bullet proof robot.

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  • johnmciv
    Hey, I just found that I could form Lexan (polycarbonate) sheet (I was using 1/8th thick) using a regular heatgun. It takes a little time to get the Lexan hot
    Message 1 of 16 , Feb 3, 2005
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      Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
      using 1/8th thick) using a regular heatgun. It takes a little time to
      get the Lexan hot enough to bend, but once it's hot enough it bends
      really easily. I was using a pretty standard heatgun. I made a small
      box to hold a controller board, but I could see that this would be a
      great way to make an insanely tough robot body. I was thinking a good
      way to melt only a small strip along the bending seam, would be to use
      a sheet metal shield with a slot cut in it, then the heat could be
      directed more accurately. Once the Lexan gives up and starts to bend
      it seems to allow 10 seconds or so to put the heatgun down and make
      the bend, before it cools and takes on it's new shape.

      Anyway, just a thought.

      ...John
    • AJ Collins
      Sounds like a good idea -- better than gluing two pieces to make a right angle. How sharp of a bend are you able to make -- i.e. what is the radius of the bend
      Message 2 of 16 , Feb 3, 2005
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        Sounds like a good idea -- better than gluing two pieces to make a right angle.

        How sharp of a bend are you able to make -- i.e. what is the radius of the bend using the .128 thickness sheet?


        AJCollins


        johnmciv <mcivor@...> wrote:


        Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
        using 1/8th thick) using a regular heatgun. It takes a little time to
        get the Lexan hot enough to bend, but once it's hot enough it bends
        really easily. I was using a pretty standard heatgun. I made a small
        box to hold a controller board, but I could see that this would be a
        great way to make an insanely tough robot body. I was thinking a good
        way to melt only a small strip along the bending seam, would be to use
        a sheet metal shield with a slot cut in it, then the heat could be
        directed more accurately. Once the Lexan gives up and starts to bend
        it seems to allow 10 seconds or so to put the heatgun down and make
        the bend, before it cools and takes on it's new shape.

        Anyway, just a thought.

        ...John





        Visit the SRS Website at http://www.seattlerobotics.org
        Yahoo! Groups Links









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        [Non-text portions of this message have been removed]
      • johnmciv
        When it is really hot, it just flows, if you bend it over a form (edge of a board or something) the inside radius is basically zero. The bend just stretches
        Message 3 of 16 , Feb 3, 2005
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          When it is really hot, it just flows, if you bend it over a form (edge
          of a board or something) the inside radius is basically zero. The bend
          just stretches through the thickness of the material.

          --- In SeattleRobotics@yahoogroups.com, AJ Collins <ajcollins99@y...>
          wrote:
          > Sounds like a good idea -- better than gluing two pieces to make a
          right angle.
          >
          > How sharp of a bend are you able to make -- i.e. what is the radius
          of the bend using the .128 thickness sheet?
          >
          >
          > AJCollins
          >
          >
          > johnmciv <mcivor@a...> wrote:
          >
          >
          > Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
          > using 1/8th thick) using a regular heatgun. It takes a little time to
          > get the Lexan hot enough to bend, but once it's hot enough it bends
          > really easily. I was using a pretty standard heatgun. I made a small
          > box to hold a controller board, but I could see that this would be a
          > great way to make an insanely tough robot body. I was thinking a good
          > way to melt only a small strip along the bending seam, would be to use
          > a sheet metal shield with a slot cut in it, then the heat could be
          > directed more accurately. Once the Lexan gives up and starts to bend
          > it seems to allow 10 seconds or so to put the heatgun down and make
          > the bend, before it cools and takes on it's new shape.
          >
          > Anyway, just a thought.
          >
          > ...John
          >
          >
          >
          >
          >
          > Visit the SRS Website at http://www.seattlerobotics.org
          > Yahoo! Groups Links
          >
          >
          >
          >
          >
          >
          >
          >
          >
          > ---------------------------------
          > Do you Yahoo!?
          > Yahoo! Mail - now with 250MB free storage. Learn more.
          >
          > [Non-text portions of this message have been removed]
        • Jay Beavers
          Dah, I ve been doing something similar. I clamp small pieces in a metal vice and then add a 1/4 x 1 piece of wood over it to help isolate the heat. I have
          Message 4 of 16 , Feb 3, 2005
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            Dah, I've been doing something similar. I clamp small pieces in a metal
            vice and then add a 1/4" x 1" piece of wood over it to help isolate the
            heat. I have a heat gun that comes with a metal fan attachment that helps
            direct the heat away from the wood and towards the joint.

            TAP Plastics also sells a heating element that can be used to bend 36" at
            once. I 'over-engineered' the element holder to add a 90 degree bend bar
            and that seems to help get good corner bends for large chassis making. You
            might take a look at something like that if you need to get into larger
            pieces.

            (I also think polycarbonate makes for a cool robot -- it's light,
            transparent, very strong, won't crack, and can be tapped.)

            -----Original Message-----
            From: johnmciv [mailto:mcivor@...]
            Sent: Thursday, February 03, 2005 8:55 PM
            To: SeattleRobotics@yahoogroups.com
            Subject: [SeattleRobotics] Bullet proof robot.



            Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
            using 1/8th thick) using a regular heatgun. It takes a little time to
            get the Lexan hot enough to bend, but once it's hot enough it bends
            really easily. I was using a pretty standard heatgun. I made a small
            box to hold a controller board, but I could see that this would be a
            great way to make an insanely tough robot body. I was thinking a good
            way to melt only a small strip along the bending seam, would be to use
            a sheet metal shield with a slot cut in it, then the heat could be
            directed more accurately. Once the Lexan gives up and starts to bend
            it seems to allow 10 seconds or so to put the heatgun down and make
            the bend, before it cools and takes on it's new shape.

            Anyway, just a thought.

            ..John





            Visit the SRS Website at http://www.seattlerobotics.org
            Yahoo! Groups Links
          • Lee Leathers
            Man.. I wish I knew this before :) I have always thought that Lexan would have a large recoil (is that the right word?) after it cools down. Does the
            Message 5 of 16 , Feb 3, 2005
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              Man.. I wish I knew this before :) I have always thought that Lexan would
              have a large recoil (is that the right word?) after it cools down.

              Does the thickness matter that much (considering you get it to the right
              temperature point?)

              This reminds me of something like this:
              http://64.233.187.104/search?q=cache:o-1b-Q13tKkJ:www.moldcompanies.com/hooblermachine/+form+plastic+vac&hl=en

              Has anyone build a plastic forming machine? (outside of what we are talking
              about here)

              thanks-Lee


              ----- Original Message -----
              From: "Jay Beavers" <Jay_C_Beavers@...>
              To: <SeattleRobotics@yahoogroups.com>
              Sent: Friday, February 04, 2005 12:22 AM
              Subject: RE: [SeattleRobotics] Bullet proof robot.


              >
              > Dah, I've been doing something similar. I clamp small pieces in a metal
              > vice and then add a 1/4" x 1" piece of wood over it to help isolate the
              > heat. I have a heat gun that comes with a metal fan attachment that helps
              > direct the heat away from the wood and towards the joint.
              >
              > TAP Plastics also sells a heating element that can be used to bend 36" at
              > once. I 'over-engineered' the element holder to add a 90 degree bend bar
              > and that seems to help get good corner bends for large chassis making.
              > You
              > might take a look at something like that if you need to get into larger
              > pieces.
              >
              > (I also think polycarbonate makes for a cool robot -- it's light,
              > transparent, very strong, won't crack, and can be tapped.)
              >
              > -----Original Message-----
              > From: johnmciv [mailto:mcivor@...]
              > Sent: Thursday, February 03, 2005 8:55 PM
              > To: SeattleRobotics@yahoogroups.com
              > Subject: [SeattleRobotics] Bullet proof robot.
              >
              >
              >
              > Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
              > using 1/8th thick) using a regular heatgun. It takes a little time to
              > get the Lexan hot enough to bend, but once it's hot enough it bends
              > really easily. I was using a pretty standard heatgun. I made a small
              > box to hold a controller board, but I could see that this would be a
              > great way to make an insanely tough robot body. I was thinking a good
              > way to melt only a small strip along the bending seam, would be to use
              > a sheet metal shield with a slot cut in it, then the heat could be
              > directed more accurately. Once the Lexan gives up and starts to bend
              > it seems to allow 10 seconds or so to put the heatgun down and make
              > the bend, before it cools and takes on it's new shape.
              >
              > Anyway, just a thought.
              >
              > ..John
              >
              >
              >
              >
              >
              > Visit the SRS Website at http://www.seattlerobotics.org
              > Yahoo! Groups Links
              >
              >
              >
              >
              >
              >
              >
              >
              >
              > Visit the SRS Website at http://www.seattlerobotics.org
              > Yahoo! Groups Links
              >
              >
              >
              >
              >
              >
              >
              >
            • Rich Chandler
              One lexan bending tip the BattleBot guys learned (some of them the hard way). Lexan is actually hydroscopic. It absorbs a small amount of water. If you over
              Message 6 of 16 , Feb 4, 2005
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                One lexan bending tip the BattleBot guys learned (some of them the hard way).
                Lexan is actually hydroscopic. It absorbs a small amount of water. If you over
                heat it, the water will form vapor bubbles in the heated area, which also
                weakens it. A long period in a warm ovev can help drive off the water, if you
                are quick to fabricate your parts before it has a chance to absorb moisture again.
              • Jay Beavers
                I haven t used any material thicker than 1/8 yet, so I couldn t tell you. The guys at TAP plastic don t like bending polycarbonate because of the potential
                Message 7 of 16 , Feb 4, 2005
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                  I haven't used any material thicker than 1/8" yet, so I couldn't tell you.

                  The guys at TAP plastic don't like bending polycarbonate because of the
                  potential for bubbles. I'm no expert, but in ~20 bends I've done so far no
                  bubbles have formed. Perhaps I'm just lucky?

                  - jcb

                  -----Original Message-----
                  From: Lee Leathers [mailto:fredit@...]
                  Sent: Thursday, February 03, 2005 10:02 PM
                  To: SeattleRobotics@yahoogroups.com
                  Subject: Re: [SeattleRobotics] Bullet proof robot.


                  Man.. I wish I knew this before :) I have always thought that Lexan would
                  have a large recoil (is that the right word?) after it cools down.

                  Does the thickness matter that much (considering you get it to the right
                  temperature point?)

                  This reminds me of something like this:
                  http://64.233.187.104/search?q=cache:o-1b-Q13tKkJ:www.moldcompanies.com/hoob
                  lermachine/+form+plastic+vac&hl=en

                  Has anyone build a plastic forming machine? (outside of what we are talking
                  about here)

                  thanks-Lee


                  ----- Original Message -----
                  From: "Jay Beavers" <Jay_C_Beavers@...>
                  To: <SeattleRobotics@yahoogroups.com>
                  Sent: Friday, February 04, 2005 12:22 AM
                  Subject: RE: [SeattleRobotics] Bullet proof robot.


                  >
                  > Dah, I've been doing something similar. I clamp small pieces in a metal
                  > vice and then add a 1/4" x 1" piece of wood over it to help isolate the
                  > heat. I have a heat gun that comes with a metal fan attachment that helps
                  > direct the heat away from the wood and towards the joint.
                  >
                  > TAP Plastics also sells a heating element that can be used to bend 36" at
                  > once. I 'over-engineered' the element holder to add a 90 degree bend bar
                  > and that seems to help get good corner bends for large chassis making.
                  > You
                  > might take a look at something like that if you need to get into larger
                  > pieces.
                  >
                  > (I also think polycarbonate makes for a cool robot -- it's light,
                  > transparent, very strong, won't crack, and can be tapped.)
                  >
                  > -----Original Message-----
                  > From: johnmciv [mailto:mcivor@...]
                  > Sent: Thursday, February 03, 2005 8:55 PM
                  > To: SeattleRobotics@yahoogroups.com
                  > Subject: [SeattleRobotics] Bullet proof robot.
                  >
                  >
                  >
                  > Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
                  > using 1/8th thick) using a regular heatgun. It takes a little time to
                  > get the Lexan hot enough to bend, but once it's hot enough it bends
                  > really easily. I was using a pretty standard heatgun. I made a small
                  > box to hold a controller board, but I could see that this would be a
                  > great way to make an insanely tough robot body. I was thinking a good
                  > way to melt only a small strip along the bending seam, would be to use
                  > a sheet metal shield with a slot cut in it, then the heat could be
                  > directed more accurately. Once the Lexan gives up and starts to bend
                  > it seems to allow 10 seconds or so to put the heatgun down and make
                  > the bend, before it cools and takes on it's new shape.
                  >
                  > Anyway, just a thought.
                  >
                  > ..John
                  >
                  >
                  >
                  >
                  >
                  > Visit the SRS Website at http://www.seattlerobotics.org
                  > Yahoo! Groups Links
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  > Visit the SRS Website at http://www.seattlerobotics.org
                  > Yahoo! Groups Links
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                  >




                  Visit the SRS Website at http://www.seattlerobotics.org
                  Yahoo! Groups Links
                • Rob Purdy
                  Could also be you just haven t got it that hot. I haven t had any bubble appear un til it was almost floppy soft. Using a heat gun I ve never had it bubble
                  Message 8 of 16 , Feb 4, 2005
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                    Could also be you just haven't got it that hot. I haven't had any bubble
                    appear un til it was almost floppy soft. Using a heat gun I've never had it
                    bubble buti t takes a lot longer and the heat spreads a lot farther. I've
                    use a micro torch. the heat stays in a much smaller area but it takes a lot
                    more skill.

                    Rob.


                    ----Original Message Follows----
                    From: "Jay Beavers" <Jay_C_Beavers@...>
                    Reply-To: SeattleRobotics@yahoogroups.com
                    To: <SeattleRobotics@yahoogroups.com>
                    Subject: RE: [SeattleRobotics] Bullet proof robot.
                    Date: Fri, 4 Feb 2005 17:23:50 -0800


                    I haven't used any material thicker than 1/8" yet, so I couldn't tell you.

                    The guys at TAP plastic don't like bending polycarbonate because of the
                    potential for bubbles. I'm no expert, but in ~20 bends I've done so far no
                    bubbles have formed. Perhaps I'm just lucky?

                    - jcb

                    -----Original Message-----
                    From: Lee Leathers [mailto:fredit@...]
                    Sent: Thursday, February 03, 2005 10:02 PM
                    To: SeattleRobotics@yahoogroups.com
                    Subject: Re: [SeattleRobotics] Bullet proof robot.


                    Man.. I wish I knew this before :) I have always thought that Lexan would
                    have a large recoil (is that the right word?) after it cools down.

                    Does the thickness matter that much (considering you get it to the right
                    temperature point?)

                    This reminds me of something like this:
                    http://64.233.187.104/search?q=cache:o-1b-Q13tKkJ:www.moldcompanies.com/hoob
                    lermachine/+form+plastic+vac&hl=en

                    Has anyone build a plastic forming machine? (outside of what we are talking
                    about here)

                    thanks-Lee


                    ----- Original Message -----
                    From: "Jay Beavers" <Jay_C_Beavers@...>
                    To: <SeattleRobotics@yahoogroups.com>
                    Sent: Friday, February 04, 2005 12:22 AM
                    Subject: RE: [SeattleRobotics] Bullet proof robot.


                    >
                    > Dah, I've been doing something similar. I clamp small pieces in a metal
                    > vice and then add a 1/4" x 1" piece of wood over it to help isolate the
                    > heat. I have a heat gun that comes with a metal fan attachment that
                    helps
                    > direct the heat away from the wood and towards the joint.
                    >
                    > TAP Plastics also sells a heating element that can be used to bend 36" at
                    > once. I 'over-engineered' the element holder to add a 90 degree bend bar
                    > and that seems to help get good corner bends for large chassis making.
                    > You
                    > might take a look at something like that if you need to get into larger
                    > pieces.
                    >
                    > (I also think polycarbonate makes for a cool robot -- it's light,
                    > transparent, very strong, won't crack, and can be tapped.)
                    >
                    > -----Original Message-----
                    > From: johnmciv [mailto:mcivor@...]
                    > Sent: Thursday, February 03, 2005 8:55 PM
                    > To: SeattleRobotics@yahoogroups.com
                    > Subject: [SeattleRobotics] Bullet proof robot.
                    >
                    >
                    >
                    > Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
                    > using 1/8th thick) using a regular heatgun. It takes a little time to
                    > get the Lexan hot enough to bend, but once it's hot enough it bends
                    > really easily. I was using a pretty standard heatgun. I made a small
                    > box to hold a controller board, but I could see that this would be a
                    > great way to make an insanely tough robot body. I was thinking a good
                    > way to melt only a small strip along the bending seam, would be to use
                    > a sheet metal shield with a slot cut in it, then the heat could be
                    > directed more accurately. Once the Lexan gives up and starts to bend
                    > it seems to allow 10 seconds or so to put the heatgun down and make
                    > the bend, before it cools and takes on it's new shape.
                    >
                    > Anyway, just a thought.
                    >
                    > ..John
                    >
                    >
                    >
                    >
                    >
                    > Visit the SRS Website at http://www.seattlerobotics.org
                    > Yahoo! Groups Links
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    > Visit the SRS Website at http://www.seattlerobotics.org
                    > Yahoo! Groups Links
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                    >




                    Visit the SRS Website at http://www.seattlerobotics.org
                    Yahoo! Groups Links









                    Visit the SRS Website at http://www.seattlerobotics.org
                    Yahoo! Groups Links
                  • Kenneth Maxon
                    You were probably looking for the word hygroscopic with a g as opposed to a d . -Kenneth (Unit 3 s in trouble and it s scared out of its wits) -Geddy Lee
                    Message 9 of 16 , Feb 4, 2005
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                      You were probably looking for the word hygroscopic with a "g" as opposed to
                      a "d".

                      -Kenneth
                      (Unit 3's in trouble and it's scared out of its wits) -Geddy Lee
                      ----- Original Message -----
                      From: "Rich Chandler" <rchandler@...>
                      To: <SeattleRobotics@yahoogroups.com>
                      Sent: Friday, February 04, 2005 1:12 PM
                      Subject: Re: [SeattleRobotics] Bullet proof robot.


                      >
                      > One lexan bending tip the BattleBot guys learned (some of them the hard
                      way).
                      > Lexan is actually hydroscopic. It absorbs a small amount of water. If
                      you over
                      > heat it, the water will form vapor bubbles in the heated area, which also
                      > weakens it. A long period in a warm ovev can help drive off the water, if
                      you
                      > are quick to fabricate your parts before it has a chance to absorb
                      moisture again.
                      >
                      >
                      > Visit the SRS Website at http://www.seattlerobotics.org
                      > Yahoo! Groups Links
                      >
                      >
                      >
                      >
                      >
                      >
                      >
                      >
                    • Jerry Rutherford
                      Check out Spectar from Eastman Chemicals. It is less expensive than Lexan (polycarbonates) has excellent thermoforming properties, and unlike acrylic... bends
                      Message 10 of 16 , Feb 5, 2005
                      • 0 Attachment
                        Check out Spectar from Eastman Chemicals. It is less expensive than
                        Lexan (polycarbonates) has excellent thermoforming properties, and
                        unlike acrylic... bends well even at room temperature. Pretty tough
                        stuff. I am trying to get it to laser cut... but it has a tendency to
                        reseal it's self.

                        Read more here... check out the movie.
                        http://www.eastman.com/Brands/Spectar/

                        Jerry
                      • Jay Prince
                        I have a few small bubbles in the first bends I made... doesn t seem to be a problem, the part is rather rigid-- more rigid than it would be if it were
                        Message 11 of 16 , Feb 6, 2005
                        • 0 Attachment
                          I have a few small bubbles in the first bends I made... doesn't seem
                          to be a problem, the part is rather rigid-- more rigid than it would
                          be if it were straight, for instance.

                          I think the important thing, especially with thicker lexan, is to make
                          the heating even.


                          On Fri, 04 Feb 2005 17:42:34 -0800, Rob Purdy <kb7wnz@...> wrote:
                          >
                          > Could also be you just haven't got it that hot. I haven't had any bubble
                          > appear un til it was almost floppy soft. Using a heat gun I've never had it
                          > bubble buti t takes a lot longer and the heat spreads a lot farther. I've
                          > use a micro torch. the heat stays in a much smaller area but it takes a lot
                          > more skill.
                          >
                          > Rob.
                          >
                          > ----Original Message Follows----
                          > From: "Jay Beavers" <Jay_C_Beavers@...>
                          > Reply-To: SeattleRobotics@yahoogroups.com
                          > To: <SeattleRobotics@yahoogroups.com>
                          > Subject: RE: [SeattleRobotics] Bullet proof robot.
                          > Date: Fri, 4 Feb 2005 17:23:50 -0800
                          >
                          >
                          > I haven't used any material thicker than 1/8" yet, so I couldn't tell you.
                          >
                          > The guys at TAP plastic don't like bending polycarbonate because of the
                          > potential for bubbles. I'm no expert, but in ~20 bends I've done so far no
                          > bubbles have formed. Perhaps I'm just lucky?
                          >
                          > - jcb
                          >
                          > -----Original Message-----
                          > From: Lee Leathers [mailto:fredit@...]
                          > Sent: Thursday, February 03, 2005 10:02 PM
                          > To: SeattleRobotics@yahoogroups.com
                          > Subject: Re: [SeattleRobotics] Bullet proof robot.
                          >
                          > Man.. I wish I knew this before :) I have always thought that Lexan would
                          > have a large recoil (is that the right word?) after it cools down.
                          >
                          > Does the thickness matter that much (considering you get it to the right
                          > temperature point?)
                          >
                          > This reminds me of something like this:
                          > http://64.233.187.104/search?q=cache:o-1b-Q13tKkJ:www.moldcompanies.com/hoob
                          > lermachine/+form+plastic+vac&hl=en
                          >
                          > Has anyone build a plastic forming machine? (outside of what we are talking
                          > about here)
                          >
                          > thanks-Lee
                          >
                          > ----- Original Message -----
                          > From: "Jay Beavers" <Jay_C_Beavers@...>
                          > To: <SeattleRobotics@yahoogroups.com>
                          > Sent: Friday, February 04, 2005 12:22 AM
                          > Subject: RE: [SeattleRobotics] Bullet proof robot.
                          >
                          > >
                          > > Dah, I've been doing something similar. I clamp small pieces in a metal
                          > > vice and then add a 1/4" x 1" piece of wood over it to help isolate the
                          > > heat. I have a heat gun that comes with a metal fan attachment that
                          > helps
                          > > direct the heat away from the wood and towards the joint.
                          > >
                          > > TAP Plastics also sells a heating element that can be used to bend 36" at
                          > > once. I 'over-engineered' the element holder to add a 90 degree bend bar
                          > > and that seems to help get good corner bends for large chassis making.
                          > > You
                          > > might take a look at something like that if you need to get into larger
                          > > pieces.
                          > >
                          > > (I also think polycarbonate makes for a cool robot -- it's light,
                          > > transparent, very strong, won't crack, and can be tapped.)
                          > >
                          > > -----Original Message-----
                          > > From: johnmciv [mailto:mcivor@...]
                          > > Sent: Thursday, February 03, 2005 8:55 PM
                          > > To: SeattleRobotics@yahoogroups.com
                          > > Subject: [SeattleRobotics] Bullet proof robot.
                          > >
                          > >
                          > >
                          > > Hey, I just found that I could form Lexan (polycarbonate) sheet (I was
                          > > using 1/8th thick) using a regular heatgun. It takes a little time to
                          > > get the Lexan hot enough to bend, but once it's hot enough it bends
                          > > really easily. I was using a pretty standard heatgun. I made a small
                          > > box to hold a controller board, but I could see that this would be a
                          > > great way to make an insanely tough robot body. I was thinking a good
                          > > way to melt only a small strip along the bending seam, would be to use
                          > > a sheet metal shield with a slot cut in it, then the heat could be
                          > > directed more accurately. Once the Lexan gives up and starts to bend
                          > > it seems to allow 10 seconds or so to put the heatgun down and make
                          > > the bend, before it cools and takes on it's new shape.
                          > >
                          > > Anyway, just a thought.
                          > >
                          > > ..John
                          > >
                          > >
                          > >
                          > >
                          > >
                          > > Visit the SRS Website at http://www.seattlerobotics.org
                          > > Yahoo! Groups Links
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > > Visit the SRS Website at http://www.seattlerobotics.org
                          > > Yahoo! Groups Links
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          > >
                          >
                          > Visit the SRS Website at http://www.seattlerobotics.org
                          > Yahoo! Groups Links
                          >
                          > Visit the SRS Website at http://www.seattlerobotics.org
                          > Yahoo! Groups Links
                          >
                          > Visit the SRS Website at http://www.seattlerobotics.org
                          > Yahoo! Groups Links
                          >
                          >
                          >
                          >
                          >
                        • Richard Greenway
                          Speaking of heat forming polycarbonate (Lexan(TM)) you might want to look into some of the more extreme computer case mods. Many seem to be using custom bent
                          Message 12 of 16 , Feb 6, 2005
                          • 0 Attachment
                            Speaking of heat forming polycarbonate (Lexan(TM)) you might want to
                            look into some of the more extreme computer case mods. Many seem to be
                            using custom bent lexan, with a fair amount of description and
                            discussion of various heating and form suggestions. Here are a couple of
                            examples of cases using this.


                            http://bit-tech.net/article/134/3


                            http://bit-tech.net/article/114/


                            Richard, AKA Fenchurch
                            http://www.fenchurch.org


                            On Sun, 2005-02-06 at 01:48, Jay Prince wrote:
                            > I have a few small bubbles in the first bends I made... doesn't seem
                            > to be a problem, the part is rather rigid-- more rigid than it would
                            > be if it were straight, for instance.
                            <Snip>
                          • Larry Barello
                            These mod articles all deal with Acrylic (aka Plexiglas) which is *EASY* to cut, bend and weld. Acrylic also easily shatters... Glass Jaw would be an
                            Message 13 of 16 , Feb 6, 2005
                            • 0 Attachment
                              These mod articles all deal with Acrylic (aka Plexiglas) which is *EASY* to
                              cut, bend and weld. Acrylic also easily shatters...

                              "Glass Jaw" would be an appropriate substitute for "Bullet Proof" in the
                              subject if made out of Acrylic.

                              Still, pretty cool computer cases!

                              -----Original Message-----
                              From: Richard Greenway


                              Speaking of heat forming polycarbonate (Lexan(TM)) you might want to
                              look into some of the more extreme computer case mods. Many seem to be
                              using custom bent lexan, with a fair amount of description and
                              discussion of various heating and form suggestions. Here are a couple of
                              examples of cases using this.


                              http://bit-tech.net/article/134/3


                              http://bit-tech.net/article/114/


                              Richard, AKA Fenchurch
                              http://www.fenchurch.org
                            • Jay Beavers
                              Yep, I started out with acrylic, but it shatters too easily. It s actually hard to just drill acrylic without shattering it -- it turns out you need special
                              Message 14 of 16 , Feb 6, 2005
                              • 0 Attachment
                                Yep, I started out with acrylic, but it shatters too easily. It's actually
                                hard to just drill acrylic without shattering it -- it turns out you need
                                special drill bits that act more delicately upon the material to prevent
                                shattering. I also shattered it from time to time when using power saws and
                                moving along too quickly.

                                Polycarbonate is much easier to work with -- not only does it not shatter
                                but it has enough strength that I can tap threads into it. Now I have much
                                cleaner chassis where I screw my components directly into the polycarbonate
                                without needing a nut on the other side. This also makes it much easier to
                                mount & unmount things since I only need access to one side of the sheet.

                                I haven't found polycarbonate to be too expensive. I'm generally paying
                                around $7-$10 for each "cut to order" sheet, when working on ~ 3'x2' sized
                                pieces. As I mentioned before, the bends at $7.50 each (at TAP Plastics)
                                were costing me much more than the polycarbonate itself, but that's easily
                                fixed by buying your own heating element.

                                -----Original Message-----
                                From: Larry Barello [mailto:yahoo@...]
                                Sent: Sunday, February 06, 2005 7:22 AM
                                To: SeattleRobotics@yahoogroups.com
                                Subject: RE: [SeattleRobotics] Bullet proof robot.


                                These mod articles all deal with Acrylic (aka Plexiglas) which is *EASY* to
                                cut, bend and weld. Acrylic also easily shatters...

                                "Glass Jaw" would be an appropriate substitute for "Bullet Proof" in the
                                subject if made out of Acrylic.

                                Still, pretty cool computer cases!

                                -----Original Message-----
                                From: Richard Greenway


                                Speaking of heat forming polycarbonate (Lexan(TM)) you might want to
                                look into some of the more extreme computer case mods. Many seem to be
                                using custom bent lexan, with a fair amount of description and
                                discussion of various heating and form suggestions. Here are a couple of
                                examples of cases using this.


                                http://bit-tech.net/article/134/3


                                http://bit-tech.net/article/114/


                                Richard, AKA Fenchurch
                                http://www.fenchurch.org



                                Visit the SRS Website at http://www.seattlerobotics.org
                                Yahoo! Groups Links
                              • Jay Prince
                                What thickness of lexan are you working with, Jay? I ve found 1/8th to be fairly rigid, but don t think I could tap it... (I m working on an antweight
                                Message 15 of 16 , Feb 7, 2005
                                • 0 Attachment
                                  What thickness of lexan are you working with, Jay? I've found 1/8th
                                  to be fairly rigid, but don't think I could tap it... (I'm working on
                                  an antweight combat robot.) I recently saw some 1/4" lexan that
                                  someone had tapped edgewise. Doing that makes building a box pretty
                                  easy, just cut the sides, tap, and screw the tops and bottoms on.

                                  Also, I've been told that JB weld does not mix well with
                                  polycarbonate, in case anyone's tempted.


                                  On Sun, 6 Feb 2005 10:34:36 -0800, Jay Beavers <Jay_C_Beavers@...> wrote:
                                  >
                                  > Yep, I started out with acrylic, but it shatters too easily. It's actually
                                  > hard to just drill acrylic without shattering it -- it turns out you need
                                  > special drill bits that act more delicately upon the material to prevent
                                  > shattering. I also shattered it from time to time when using power saws and
                                  > moving along too quickly.
                                  >
                                  > Polycarbonate is much easier to work with -- not only does it not shatter
                                  > but it has enough strength that I can tap threads into it. Now I have much
                                  > cleaner chassis where I screw my components directly into the polycarbonate
                                  > without needing a nut on the other side. This also makes it much easier to
                                  > mount & unmount things since I only need access to one side of the sheet.
                                  >
                                  > I haven't found polycarbonate to be too expensive. I'm generally paying
                                  > around $7-$10 for each "cut to order" sheet, when working on ~ 3'x2' sized
                                  > pieces. As I mentioned before, the bends at $7.50 each (at TAP Plastics)
                                  > were costing me much more than the polycarbonate itself, but that's easily
                                  > fixed by buying your own heating element.
                                  >
                                  > -----Original Message-----
                                  > From: Larry Barello [mailto:yahoo@...]
                                  > Sent: Sunday, February 06, 2005 7:22 AM
                                  > To: SeattleRobotics@yahoogroups.com
                                  > Subject: RE: [SeattleRobotics] Bullet proof robot.
                                  >
                                  > These mod articles all deal with Acrylic (aka Plexiglas) which is *EASY* to
                                  > cut, bend and weld. Acrylic also easily shatters...
                                  >
                                  > "Glass Jaw" would be an appropriate substitute for "Bullet Proof" in the
                                  > subject if made out of Acrylic.
                                  >
                                  > Still, pretty cool computer cases!
                                  >
                                  > -----Original Message-----
                                  > From: Richard Greenway
                                  >
                                  > Speaking of heat forming polycarbonate (Lexan(TM)) you might want to
                                  > look into some of the more extreme computer case mods. Many seem to be
                                  > using custom bent lexan, with a fair amount of description and
                                  > discussion of various heating and form suggestions. Here are a couple of
                                  > examples of cases using this.
                                  >
                                  > http://bit-tech.net/article/134/3
                                  >
                                  > http://bit-tech.net/article/114/
                                  >
                                  > Richard, AKA Fenchurch
                                  > http://www.fenchurch.org
                                  >
                                  > Visit the SRS Website at http://www.seattlerobotics.org
                                  > Yahoo! Groups Links
                                  >
                                  > Visit the SRS Website at http://www.seattlerobotics.org
                                  > Yahoo! Groups Links
                                  >
                                  >
                                  >
                                  >
                                  >
                                • Jay Beavers
                                  1/8 I m not attempting to tap it edge-wise. I m bending it to form a U shell and then drilling/tapping the face rather than the edge. ... From: Jay
                                  Message 16 of 16 , Feb 7, 2005
                                  • 0 Attachment
                                    1/8" I'm not attempting to tap it edge-wise. I'm bending it to form a U shell and then drilling/tapping the face rather than the edge.
                                    ----- Original Message -----
                                    From: Jay Prince<mailto:jayprince@...>
                                    To: SeattleRobotics@yahoogroups.com<mailto:SeattleRobotics@yahoogroups.com>
                                    Sent: Monday, February 07, 2005 4:54 PM
                                    Subject: Re: [SeattleRobotics] Bullet proof robot.



                                    What thickness of lexan are you working with, Jay? I've found 1/8th
                                    to be fairly rigid, but don't think I could tap it... (I'm working on
                                    an antweight combat robot.) I recently saw some 1/4" lexan that
                                    someone had tapped edgewise. Doing that makes building a box pretty
                                    easy, just cut the sides, tap, and screw the tops and bottoms on.

                                    Also, I've been told that JB weld does not mix well with
                                    polycarbonate, in case anyone's tempted.


                                    On Sun, 6 Feb 2005 10:34:36 -0800, Jay Beavers <Jay_C_Beavers@...<mailto:Jay_C_Beavers@...>> wrote:
                                    >
                                    > Yep, I started out with acrylic, but it shatters too easily. It's actually
                                    > hard to just drill acrylic without shattering it -- it turns out you need
                                    > special drill bits that act more delicately upon the material to prevent
                                    > shattering. I also shattered it from time to time when using power saws and
                                    > moving along too quickly.
                                    >
                                    > Polycarbonate is much easier to work with -- not only does it not shatter
                                    > but it has enough strength that I can tap threads into it. Now I have much
                                    > cleaner chassis where I screw my components directly into the polycarbonate
                                    > without needing a nut on the other side. This also makes it much easier to
                                    > mount & unmount things since I only need access to one side of the sheet.
                                    >
                                    > I haven't found polycarbonate to be too expensive. I'm generally paying
                                    > around $7-$10 for each "cut to order" sheet, when working on ~ 3'x2' sized
                                    > pieces. As I mentioned before, the bends at $7.50 each (at TAP Plastics)
                                    > were costing me much more than the polycarbonate itself, but that's easily
                                    > fixed by buying your own heating element.
                                    >
                                    > -----Original Message-----
                                    > From: Larry Barello [mailto:yahoo@...]
                                    > Sent: Sunday, February 06, 2005 7:22 AM
                                    > To: SeattleRobotics@yahoogroups.com<mailto:SeattleRobotics@yahoogroups.com>
                                    > Subject: RE: [SeattleRobotics] Bullet proof robot.
                                    >
                                    > These mod articles all deal with Acrylic (aka Plexiglas) which is *EASY* to
                                    > cut, bend and weld. Acrylic also easily shatters...
                                    >
                                    > "Glass Jaw" would be an appropriate substitute for "Bullet Proof" in the
                                    > subject if made out of Acrylic.
                                    >
                                    > Still, pretty cool computer cases!
                                    >
                                    > -----Original Message-----
                                    > From: Richard Greenway
                                    >
                                    > Speaking of heat forming polycarbonate (Lexan(TM)) you might want to
                                    > look into some of the more extreme computer case mods. Many seem to be
                                    > using custom bent lexan, with a fair amount of description and
                                    > discussion of various heating and form suggestions. Here are a couple of
                                    > examples of cases using this.
                                    >
                                    > http://bit-tech.net/article/134/3<http://bit-tech.net/article/134/3>
                                    >
                                    > http://bit-tech.net/article/114/<http://bit-tech.net/article/114/>
                                    >
                                    > Richard, AKA Fenchurch
                                    > http://www.fenchurch.org<http://www.fenchurch.org/>
                                    >
                                    > Visit the SRS Website at http://www.seattlerobotics.org<http://www.seattlerobotics.org/>
                                    > Yahoo! Groups Links
                                    >
                                    > Visit the SRS Website at http://www.seattlerobotics.org<http://www.seattlerobotics.org/>
                                    > Yahoo! Groups Links
                                    >
                                    >
                                    >
                                    >
                                    >


                                    Visit the SRS Website at http://www.seattlerobotics.org<http://www.seattlerobotics.org/>
                                    Yahoo! Groups Links









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