Crossbows - Everything about Building, Modding, and Using your Crossbow Gear

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by JacobL Tue Jan 09, 2018 6:38 pm

    Hello all!


    Fresh Blood

    Doesn't mean
    I'm new to crossbows

    Fresh Blood Doesn't meanI'm new to crossbows

    Posts : 1
    Join date : 2017-07-04

    Hello all!

    Post by Tarzan65 on Thu Jul 06, 2017 10:54 am

    Im from Sweden and tried to carve myself a longbow some years ago. I soon stated that this was not my path. Instead I started thinking alternative sources for power. I soon came up with steelsprings. Im not sure Ide never seen such konstructions at that time so I started blindly. I ended up with one maxisized crossbow, I cant decide if its a Big Bertha or just a Fat Bastard, and a mini.

    The maxi had a open stock at the rear that was supposed to contain some kind of industrial monster spring. I never found one, so after some trials I got my hands on trampolinesprings. At the frontpart of the T-shaped stock I planned to put 4 springs on either side. I tested to shoot it with 2 springs on both sides and it was obvious that maxi suffered from heave big limbs and a string that had a lot of stretch.

    The mini had 2 exhaustsprings from a endurobike. Quite hard for the slim size. I fitted small wheels on the limbs to get a slightly longer pull. It felt good when I cocked it, but when I shot it I was a little dissapointed. It works for shooting beercans from 5 meters but not more..

    Now I am eager to try to develop my crossbowbuilding. Ive read a lot on the net and Im interested in trying to build an inswinger. First I want to try to rebuild what I can from the old ones. Maxi has a doubledecker design on the upper T-part so I cant rebuild it to an inswinger whithout alter the hole stock. It will have to bend to the traditional side but I will do a string arrangement that will (hopefully) make the limbs bend all the way in to the stock like a flipper.

    The mini should be able to work in an inswingermoderation. I found some small pressuresprings Id like to try to put into the equation.

    Aside from these springprojects Ive read a lot about rubber and watched several of Jörgs films. You can have a rubber that makes drawlength infinitive. But is it always better? I You want to shot heavy objects at close range for maximal destruction ( I think that is Jörgs motto.) it works well but if You want maximum speed to a light arrow Im afraid that thick heavy rubber will make the speed suffer. In a test I found from a swedish slingshotshop, the thinnest tubes were the fastest. The setup with triple small rubbers was faster then the thickest rubbertubes, although I think that the big tube had more pounds then the tiny trippel together it was slower.

    I wonder if its enough to increas the speed of the thickest rubber by combining it to limbs or if multiple smaller tubes is the better option? One of the inswingers on this forum uses small officerubbers and that seems to work well enough.

    In contradiction to long and slow heavy rubbers we have Jörgs James Bond-gun that seems to work very well with a supershort thick rubber. It seems to be a perfect ratio in there to be found between rubber length and rubber thickness.

    I have already ordered some heavy speargun rubbers so I will try them for the next projekts.

    Can anyone tell me if its a given difference in power between springs and rubbers? Ive read quite a lot but never seen a comparizon what I can remember..

      Current date/time is Fri Mar 23, 2018 7:00 am