First Handcatapult Slingbow

Discussion in 'Show off your homemades!' started by ahlver jonsson, Oct 2, 2012.

  1. ahlver jonsson

    ahlver jonsson New Member

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    hello every body,<br><br>since sunday i'm working on this:<br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0274.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0275.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0276.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0278.jpg" border="0" alt=""><br><br>that was the work of yesterday<br><br>and tonight i've done the first testing with some rubber from a local store :<br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0279.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0281.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0280.jpg" border="0" alt=""><br><br>there's a lot more to do in the next days, but i'm pretty satisfied for the moment. <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2"><br><br>next to come : Arrow rest, rail and EOTECH, rubber stopper with foam for the noise, and some final cosmetic work....
     
  2. brat boon

    brat boon New Member

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    <div>cool</div><div class="clear"></div><div class="signature_div">
    <br><strong>at school, I am a slingshot expert</strong> <img src="http://illiweb.com/fa/i/smiles/icon_biggrin.png" alt="Very Happy" longdesc="1"><br><br>on this forum a noob <img src="http://illiweb.com/fa/i/smiles/icon_neutral.gif" alt="Neutral" longdesc="20">
    </div>
     

  3. Antraxx

    Antraxx #7

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    Looks good so far, but i would swap the three rods that rest on your forearm with two wide leatherstripes.<br>larger surface to rest on and more comfortable i bet.
     
  4. ahlver jonsson

    ahlver jonsson New Member

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    yes leather will be added <img src="http://illiweb.com/fa/i/smiles/icon_wink.gif" alt="Wink" longdesc="15"> the rodds are here for strengh <img src="http://illiweb.com/fa/i/smiles/icon_smile.gif" alt="Smile" longdesc="2">
     
  5. onnod

    onnod Im from Holland, isnt that weird?

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  6. ahlver jonsson

    ahlver jonsson New Member

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    Upgrade !<br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0283.jpg" border="0" alt=""><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0282.jpg" border="0" alt=""><br><br>arrow rest added, leather on the arm rest <img src="http://illiweb.com/fa/i/smiles/icon_wink.gif" alt="Wink" longdesc="15"><br><br>rubber change, the first one was 25 pounds, now its a 50 pounds, i'll need a quick release because now it's almost impossible to draw at full lenght with one finger in the loop.<br>the rubber is made of 3 piece of 23 cm with 5 cm at base and 3 cm at the end. on each side. so it's a 50 pounds (23 kg) at 90 cm.
     
  7. ahlver jonsson

    ahlver jonsson New Member

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    <img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0284.jpg" border="0" alt=""><br><br>today, i've made a Quick release for my slingbow, for the moment it's pretty rough, but i have to do some cosmetic action <img src="http://illiweb.com/fa/i/smiles/icon_wink.gif" alt="Wink" longdesc="15">
     
  8. onnod

    onnod Im from Holland, isnt that weird?

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  9. alpha

    alpha New Member

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    Very creative, looks very imposing and impressive. <img src="http://illiweb.com/fa/i/smiles/icon_biggrin.png" alt="Very Happy" longdesc="1">
     
  10. ahlver jonsson

    ahlver jonsson New Member

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    first real firering test today, i was quite surprise, the arrow rest is made for 8mm arrow and i fire 6 mm arrows, but i hold a circle of 30 cm at 10meters.<br>not bad for a beginner with a toy without sight.<br><br>and i'm starting to build arrows, does someone knows some cheap broadhead for aluminum shaft withot insert ?
     
  11. tokSick

    tokSick Senior Member

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    Ca a l' air d'être méchament puissant ce" joujou". I think you better take the rods for the forearm support away. If you leave only the leather it will take the shape of your arm and it will be more comfortable and stable when shootin'. That means more accurate too. Don' t you think?... Anyways, nice job mate. With that weapon you could hunt big game i guess.
     
  12. JoergS

    JoergS Administrator

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    You should think about extending the fork (the rubber attachments) forward to eliminate the dead play in the rubber bands. That would increase the power quite significantly.<br><br>
     
  13. ahlver jonsson

    ahlver jonsson New Member

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    thanks joerg, you're full of inspiration, i have a new idea because of you ! roller !!
     
  14. JoergS

    JoergS Administrator

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    As long as you have a wrist stabilizer, rollers aren't needed at all. You need rollers if you want draw length increase without wrist braces. But if you have a brace, you can simply forward extend the fork. No friction, and much less work.
     
  15. ahlver jonsson

    ahlver jonsson New Member

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    so here is i think the final design of my hand catapult, wich now look like a roman scorpio ! <br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0287.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0288.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0289.jpg" border="0" alt=""><br><br><img src="http://i303.photobucket.com/albums/nn137/gott76/slingbow/SAM_0290.jpg" border="0" alt=""><br><br>the arrow sit in the rest perfectly, it doesn't move.<br>i don't know how much power i've win.... but it's really harder than before.
     
  16. onnod

    onnod Im from Holland, isnt that weird?

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  17. ahlver jonsson

    ahlver jonsson New Member

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    made some trying tonigh with different thera band gold rubber configuration.<br>and i think i found a good compromise<br>a 26 cm long with 4 cm at the begining and 2 cm at the end.<br>with the roller system i'm winning 15 cm of draw lengh, so this rubber is a 45 lbs at 95 cm.<br>
     
  18. Theodor

    Theodor New Member

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    nice job on the design and the shape!<br><br>May I express my concern regarding the two handles of the catapult which rest on your hand? <br>I think it would be safer if they were made out of plywood, which has strength in all directions (or even whole pieces of wood) ...<br>The wood you have used is made out of small pieces glued together by finger joints...thererefore, there is no continuation of the woodgrain and thus the handles have serious weakpoints...
     
  19. ahlver jonsson

    ahlver jonsson New Member

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    yes, this modification is planned in the futur. <br>this slingbow is a try, with scrap wood from my stock.<br>now i'm working on a bow which look like a compound bow, and i'm planning to do it in marine plywood.<br><br>a question for you guys, is the Oukoumé plywood is good for making slingbow and co ?