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  • The Sad Demise of the Brake Line
    The brake line was hard, difficult to bend smoothly, and being a tube, hollow from inside, developed sharp crease at bends, where it reached to point of breaking. It was formed into "Franklin" in such inaccurate dimensions & such a poor shape, I decided not to proceed further.
    Please see below the picture of the ill-fated brake line converted into mutilated Franklin....sigh.....another failed experiment.

    DSC03211-R.jpg

    I will now purchase from a local metal store (Metal Supermarket), a solid rod or wire of soft copper (grade C110) which is easy to bend & shape, and being solid, will not develop sharp creases at point of bending.

    Metalsupermarket branch in Mississauga (City Adjacent to Toronto, where CYYZ, the Toronto International Airport is located)
    http://metalsupermarkets.com/mississauga/metals/

    Various Grades of Copper - C110 is suitable for antenna making as it is malleable and ductile*** & is not very costly:
    http://metalsupermarkets.com/metals/...-guide/copper/

    *** ductility is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched into a wire. Malleability, a similar property, is a material's ability to deform under compressive stress; this is often characterized by the material's ability to form a thin sheet by hammering or rolling. Both of these mechanical properties are aspects of plasticity, the extent to which a solid material can be plastically deformed without fracture.
    Last edited by abcd567; 2014-08-04, 02:04.

    Comment


    • I should have purchased a tube bending tool, something like these, or better.

      NEW KD Tools # 2517 Tubing Bender 4 Size 3/16" 1/4" 5/16" 3/8" MADE IN USA!
      http://m.ebay.ca/itm?itemId=231037625683&pAction=VI
      $(KGrHqN,!ocFINGFN78lBSFS2dvJ2!~~60_12.JPG

      Brake Fuel AC Refrigerant Line Bending Pliers Tube Bender
      http://www.ebay.ca/itm/Brake-Fuel-AC...item3cd7206dcd
      $_12.JPG

      K-D 2189 Tube Bender
      http://www.ebay.ca/itm/K-D-2189-Tube...item4cf096f9c9
      !ByhyPKQEGk~$(KGrHqEOKjkEwPT!sC!TBMSH9eH1D!~~_12.JPG

      GENERAL TUBING BENDERS No. S-106 SET OF 6 NEW IN PACKAGE 1/4" THRU 5/8" U.S.A.
      http://www.ebay.ca/itm/GENERAL-TUBIN...item3392d83cf5
      $_12.JPG


      3 in 1 Pipe Tube Bender 1/4" 5/16" 3/8" OD Tubing 90 degree 11" Long Hand Tool
      http://www.ebay.ca/itm/3-in-1-Pipe-T...item56649af242


      Heavy Duty Tube Pipe Bender 3-in-1 6 8 10mm 180°Straight Angle Plumbing AC HVAC
      http://www.ebay.ca/itm/Heavy-Duty-Tu...item27e39e1db4
      $_12.JPG
      Last edited by abcd567; 2014-08-03, 08:10.

      Comment


      • Hi abcd567
        Even with a pipe bending tool, I very much doubt you would have got bends as tight as you needed. Once past about 90degrees the tube tends to collapse, and I seriously doubt a 6mm 180 degree bend would be possible (even if it was filled with sand first, or using a bending spring). Aftermarket brake pipes have always been problematic, hence so many people using the Aeroquip lines on kit/race/rally cars.
        Would braided stainless be any good as an antenna :-) ? The line itself is not TOO expensive but the fittings (anodised aircraft grade aluminium) are extortionate.
        Have fun
        Terry
        Last edited by Teecee; 2014-08-03, 09:32.

        Comment


        • Originally posted by abcd567 View Post
          Today I again visited Canadian Tier & Home Depots, which were open today.
          From Canadian Tier, I purchased 3/16" dia, 4' long brake line. It is coated black from outside, but when I looked to it's end, the inside material is silver/aluminum/steel color.
          When I brought it home, I checked it with a Magnet, and the magnet cling to it. Sure, it is made of a magnetic material (steel/steel alloy/nickle alloy etc etc). I am not sure how the magnetic material will affect the phasing & matching stub's performance. Anyway, I want give it a try.

          Below are some photos of the Brake Line I have purchased:

          [ATTACH=CONFIG]4537[/ATTACH] . [ATTACH=CONFIG]4539[/ATTACH] . [ATTACH=CONFIG]4538[/ATTACH]

          It will be copper coated steel.... fine for antennae, but as you found - very brittle... to get the tight bends you require fill the tube with fine sand, and heat the bend with a blow lamp.

          Comment


          • Originally posted by Rooster View Post
            It will be copper coated steel.... fine for antennae, but as you found - very brittle... to get the tight bends you require fill the tube with fine sand, and heat the bend with a blow lamp.
            someone said seal the pipe end (bend it over), fill with salt, vibrate the pipe with an engraver or something to get the filling to pack down, then bend the other end over tight - then it might bend ok.

            I like the idea of heating it (to red heat) to bend it - only problem is not making it hot enough to make glass or something else out of the filling inside the tube.

            I'll have to make up a template on a board with some 6mm bolts stuck up in crucial places

            The pipe I have says 'Saville copper tubing to BS EN 12449 seamless 22 gauge' and is non-magnetic.

            Comment


            • Originally posted by peterhr View Post
              someone said seal the pipe end (bend it over), fill with salt, vibrate the pipe with an engraver or something to get the filling to pack down, then bend the other end over tight - then it might bend ok.

              I like the idea of heating it (to red heat) to bend it - only problem is not making it hot enough to make glass or something else out of the filling inside the tube.
              No problem there, melting point of copper is 1080 degrees (C), melting point of sand is 1723 degrees (C) so you'll be in trouble a long way before you make glass

              Comment


              • Originally posted by peterhr View Post
                ............I'll have to make up a template on a board with some 6mm bolts stuck up in crucial places.........
                Below is the template on a wooden board for 5mm dia wire/tube with 10mm & 16mm dia bolts fixed at crucial places.
                ALL dimensions are from "Center of Bolt" to "Center of Bolt".
                EDIT: Template Drawing replaced on Aug 17, 2014. Reason: Spacing of Phasing Stub Bolts corrected from 28mm to 18mm. Thanks to Dave ("trigger") for pointing out the mistake.




                EDIT: Computer simulation results for antenna made by above Template are added below

                franklin - 4elm-5mm wire-15mm phasing-10mm matching-round bend- Gain SWR Pattern.png . franklin - 4elm-5mm wire-15mm phasing-10mm matching-round bend- SWR Sweep.png . franklin - 4elm-5mm wire-15mm phasing-10mm matching-round bend-Wire data.png
                Last edited by abcd567; 2014-08-17, 16:29.

                Comment


                • Something that just occurred to me - in the UK certainly you can get 10mm electrical cable for use with 10Kw heating circuits (230v mains). The 10mm willl be cross sectional area and the cble will be multi-strand (quite chunky strand) and insulated.

                  mUvR3mCST8c4yFoV3B0C3Gw.jpg

                  If someone were to get a length of that, carefully strip it (straight as possible, no kinks) and run some solder into it 'bond' the cores into one stiff assembly - it would be just a shade over 3mm diameter
                  Last edited by peterhr; 2014-08-04, 08:05.

                  Comment


                  • @peterhr: Good idea

                    Comment


                    • Originally posted by peterhr View Post
                      Something that just occurred to me - in the UK certainly you can get 10mm electrical cable for use with 10Kw heating circuits (230v mains). The 10mm willl be cross sectional area and the cble will be multi-strand (quite chunky strand) and insulated.

                      [ATTACH=CONFIG]4557[/ATTACH]

                      If someone were to get a length of that, carefully strip it (straight as possible, no kinks) and run some solder into it 'bond' the cores into one stiff assembly - it would be just a shade over 3mm diameter
                      Would we need to strip it?
                      What about just using the Earth. I think it is about 2.8mm
                      Last edited by trigger; 2014-08-04, 19:10. Reason: Suggeted the Earth wire
                      T-EGUB1

                      Comment


                      • Originally posted by trigger View Post
                        Would we need to strip it?
                        What about just using the Earth. I think it is about 2.8mm
                        It Is necessary to strip insulation of the portion which makes impedance matching stub & phasing stubs.
                        Vertical parts can be with or without insulation.
                        See photo below.

                        Last edited by abcd567; 2014-08-04, 21:21.

                        Comment


                        • Originally posted by trigger View Post
                          Would we need to strip it?
                          What about just using the Earth. I think it is about 2.8mm
                          1m of cable could make 3 antenni

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                          • How about threading the multi-core wire through the pipe? It should help with kinks.
                            T-EGUB1

                            Comment


                            • Originally posted by trigger View Post
                              How about threading the multi-core wire through the pipe? It should help with kinks.
                              The pipe, if metallic, will itself form the antenna. The cable inside will be shielded from incoming signal and will not contribute to receiving the signal.

                              Comment


                              • Originally posted by abcd567 View Post
                                Below is the template on a wooden board for 5mm dia wire/tube with 10mm & 16mm dia bolts fixed at crucial places.
                                ALL dimensions are from "Center of Bolt" to "Center of Bolt".



                                EDIT: Computer simulation results for antenna made by above Template are added below

                                [ATTACH=CONFIG]4563[/ATTACH] . [ATTACH=CONFIG]4562[/ATTACH] . [ATTACH=CONFIG]4561[/ATTACH]

                                wow ! With this template, you can expect "mass production" of this popular antenna soon.
                                F-WSSS1 - Cats refused to Pee & Pooh on RadarBox - Running a FR24 Receiver & DVB-T Dongle 24/7 to piss off The Chief Thief.

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