Slingshots with epoxy, polyester and glassfibre

Discussion in 'General Slingshot Discussions' started by G_Y, May 29, 2013.

  1. G_Y

    G_Y aiming the less

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    Glassfibre mats with polyester or epoxy are common as base material in boats, airplanes and for racing sports. Great because not so heavy as steel, good resistance against moist, hard and a bit flexible.

    Has anybody experience to use these materials for repairing wooden ss forks, glueing metal or wooden slingshot parts together or laminating whole ss from scratch?

    Read about cold steel for repairing on metal parts and suppose it is an epoxy type glue, too.
     
  2. jt-1911

    jt-1911 Senior Member ProPlatinum

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    Allways whanted to try it and I have all the materials here so I might give it a try. No prior experience though
     

  3. Laminating of fibreglass and coal fibre is not easy.
    You need a press and a heat and a vacuuum to make a very heavy laminate without any air between the layers.

    Joe
     
  4. Ravensbull

    Ravensbull New Member

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    Very interesting question. I've been considering buying a Bondo fiberglass patch kit that has the resin,catalyst,n glass matting to make a rectangular block of it and cut a tester out of... As far as wood repair, I've found that JB woodweld is very strong,cures quickly,fills small voids n chips well,BUT I wouldn't rely on it too heavily in the event of say a broken fork on a board cut with strong bands for obvious safety reasons. I've used it alot for fill in cracks in naturals too as long as it's not structural. Works for belly fill in through-wire construction of pike fishing lures and spearing decoys too
     
  5. Ravensbull

    Ravensbull New Member

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  6. G_Y

    G_Y aiming the less

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    Nice ideas, thank you.

    It is not so hard to laminate with minor failures. If there is a form, maybe made from plaster, silicone or a wooden negative Y-form. First paint separating wax, then paint the coating first, so there is no need for sandpaper etc. Then wet-in-wet resin, then the well cutted first matting dipping with a paintbrush in the resin and then the next layer. The mat must be completely wet, but not more resin then necessary for best stability.

    In factorys they often use long glass or textile fibres instead of mats, airblown together with resin. A bit less dense and stability, but an idea to do it without mats.

    I would not make a block for cutting and shaping, it is very hard and laminated glassfibres can sting like thornes. Dust and gas are bad for health, too.

    Unfortunately it stinks like gas when laminating for a few days, because the chemical reaction resin-catalyst/hardener. So do it outside the house. Catalyst/Hardener (3%) is important: Too much and it is hard in no time, too less and it will not harden. Sometimes it is possible to harden it anyway in an oven at 70 degrees C and also for more stability 2 hours with this temperature.
     
    Last edited: May 30, 2013
  7. G_Y

    G_Y aiming the less

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    Wood often gets rotten when totally covered, depending on moisture.
     
    Last edited: Jun 13, 2013
  8. Brazilviking

    Brazilviking Thread Hijacker

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    My opinion: The best way to repair a broken wodden fork is by replacing it.....Ok, you love the fork and still want it! So you must get a steel rod that is thinner than the broken part of the fork. Drill the core of your fork and insert the rod with epoxy glue. But as Ravensbull said, be carefull with strong bands.

    Dry wood totally sealed doesn't get rotten.....you can meke it free from bacteria putting it into alchool and letting it dry before sealing it.
     
  9. sureshot_slingshot

    sureshot_slingshot Sureshot

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    Very nice discussion about vacuum forming with fiberglass. I have vacuum formed foam planes before and it was not all that hard, but the planes were made of foam and they had very smooth edges. When you vacuum form something with fiberglass and resin the object needs to have no sharp edges. And the foam planes are not like wood in the since that the wood would probably soak up some of the resin which is Ok but don't expect to get your slingshot back unless you seal your slingshot with epoxy. I do not know if any of this is helpful to you all, and I do not know for sure if this statement is 100% correct but I have a little bit of experience and this is what I can tell you from doing vacuum forming. :)