The "Homemade Raptor"-Project: Revisited!

Discussion in 'Show off your homemades!' started by FIAAO, Jan 14, 2013.

  1. FIAAO

    FIAAO Failureisalwaysanoption

    3,648
    19
    38
    Okay, some of you guys might remember an old Project of mine:<br><br><a href="http://theslingshotforum.forumotion.com/t1489-homemade-multiplex-raptor-prototype?highlight=raptor" class="postlink">The Homemade Raptor Prototype</a><br><br>That was along time ago and I didnt have much experience. Okay, lets face it: That was a total pile of junk!<br><br>So, as prototypes is made to be improved, I decided to make something usable from this basis. First, we got to look at the problems with the old one:<br><br><ul>
    <br><li>Totally weak (Not enough rubber, didnt get stretched very far, friction etc)<br>
    </li>
    <li>Very inaccurate (Uneven Power-distribution)<br>
    </li>
    <li>To short draw (No compound system was used)<br>
    </li>
    <li>Very ugly (Ill wait to improve this Before this works...)<br>
    </li>
    </ul>
    <br>Okay, thats a lot of things to improve, and I dont think that was all. Now to the fun part, how to improve the thing. I started with the original "stock" part and saved out four new heads from 12 mm ply:<br><br><img src="http://i11.servimg.com/u/f11/17/50/40/49/img_0018.jpg" border="0" alt=""><br><br>As you see, these are much more like the real thing! Now onto the things we can do to improve.<br><br>As we all know by now, rubber works best if its stretched to a factor of around 5,5. I find that hard to achieve with a mechanism like this on, that is actually used to <i>decrease </i>the distance the power-supply (ex limbs of a bow) have to travel to get the same movement from the string/ pouch and therefore also the ammo is moving. And as Joerg earlier pointed out, a pre-stretch of more than factor 3 is not very good for power (Am I right?). Luckily, I found this rubber tubing lying around at home, wich was given to me by a teacher at school earlier last year. As its made for training purposes, it do not stretch very far; Maybefactor 2 or 3. Just what we want here! I made a ring from it just to test the power of a constrictor knot and if I could use it like this. It works! Of course I have to combine several loops on each side to get some power. <br><br><img src="http://i11.servimg.com/u/f11/17/50/40/49/img_0019.jpg" border="0" alt=""><br><br><img src="http://i11.servimg.com/u/f11/17/50/40/49/img_0020.jpg" border="0" alt=""><br><br>So that pretty much solves the rubber problem(tubes lasts longer than flatbands too! <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2"> ) When I finish this post, Im going to draw up the "cams" for the bow. <br><br>//AB
     
  2. onnod

    onnod Im from Holland, isnt that weird?

    6,001
    18
    38
    good start, if this works i'll make one to
     

  3. FIAAO

    FIAAO Failureisalwaysanoption

    3,648
    19
    38
    Why not start right away? With two brains working on it it cannot fail! <img src="http://illiweb.com/fa/i/smiles/icon_biggrin.png" alt="Very Happy" longdesc="1">
     
  4. onnod

    onnod Im from Holland, isnt that weird?

    6,001
    18
    38
    well, because 7 hours of school, homework, friends(yes i have friends), sleeping and eating take a lot of time. i haven't touched a slingshot for days <img src="http://illiweb.com/fa/i/smiles/icon_sad.gif" alt="Sad" longdesc="3">
     
  5. Saderath

    Saderath Senior Member

    906
    0
    0
    That looks promising! Cant wait to see it finished....
     
  6. FIAAO

    FIAAO Failureisalwaysanoption

    3,648
    19
    38
    <table width="90%" cellspacing="1" cellpadding="0" border="0" align="center">
    <tr><td><span class="genmed"><b>onnod wrote:</b></span></td></tr>
    <tr><td class="quote">well, because 7 hours of school, homework, friends(yes i have friends), sleeping and eating take a lot of time. i haven't touched a slingshot for days <img src="http://illiweb.com/fa/i/smiles/icon_sad.gif" alt="Sad" longdesc="3">
    </td></tr>
    </table>
    <span class="postbody"><br><br>Its pretty much the same for me... Why do they not teach <u>useful</u> things in school? (A.k.a slingshot-related stuff) <img src="http://illiweb.com/fa/i/smiles/icon_lol.gif" alt="Laughing" longdesc="7"><br><br>Saderath: Thanks <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2"></span>
     
  7. FIAAO

    FIAAO Failureisalwaysanoption

    3,648
    19
    38
    I assembled one of the heads and sawed out a cam+pulley. You may start to get a feeling of how the final weapon will look like!<br><img src="http://i11.servimg.com/u/f11/17/50/40/49/pict0011.jpg" border="0" alt=""><br>I Think I may have to change the heads a bit to get this thing working. We´ll see!<br>Also I discovered that the rubberrings dont have to be that big. This is a good size too:<br><img src="http://i11.servimg.com/u/f11/17/50/40/49/pict0012.jpg" border="0" alt=""><br>//AB
     
  8. FIAAO

    FIAAO Failureisalwaysanoption

    3,648
    19
    38
    Okay, I can sadly tell that this was a failure. The stock is too small to give any satistifying drawlength. One day I might get this to work... but that day is not today <img src="http://illiweb.com/fa/i/smiles/icon_wink.gif" alt="Wink" longdesc="15">