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

Latest topics

» Chinese crossbow with auxiliary string?
by Geezer Today at 10:08 pm

» Crusader crossbow
by c sitas Today at 9:41 pm

» Yet another one
by Daniel Levesque Today at 11:51 am

» Whamo showed up, prod replacement ideas
by kenh Mon Jun 19, 2017 4:25 pm

» Renaissance Sporting crossbow
by tony a Mon Jun 19, 2017 2:10 am

» 15th century saxon prods
by Geezer Sun Jun 18, 2017 10:46 pm

» loose laminate issues
by c sitas Sun Jun 18, 2017 8:42 am

» Of Bows and Torsion Engines
by c sitas Fri Jun 16, 2017 2:55 pm

» My second crossbow
by Daniel Levesque Fri Jun 16, 2017 10:48 am

» Need to locate Windlass Crossbow, pre 1600, in Rome, Venice, or Florence
by 8fingers Tue Jun 13, 2017 11:24 pm

» Crossbow Projectiles
by Geezer Tue Jun 13, 2017 8:10 pm

» Greetings!
by OnlyHuman Mon Jun 12, 2017 7:40 am

» Anyone know what this is?
by Yuki23emma Sun Jun 11, 2017 2:54 pm

» Prod specs
by Onager Lovac Mon Jun 05, 2017 4:25 pm

» Finished Crossbow
by kenh Sat Jun 03, 2017 8:34 pm

» The Arbalist Guild - Around the World
by Turnigy Fri Jun 02, 2017 1:25 pm

» Reverse draw "compound" build
by Turnigy Fri Jun 02, 2017 1:20 pm

» Casting Resource
by White Oak Wed May 31, 2017 2:28 am

» The Road so far......
by White Oak Mon May 29, 2017 7:17 am

» GLOSSARY OF TERMS
by Onager Lovac Wed May 24, 2017 6:41 pm

» Hello from Maine
by White Oak Sun May 21, 2017 11:06 pm

» Leonardo Da Vinci string with suport-rolls
by Oppenheimer Tue May 16, 2017 11:40 am

» Compact repeating compound project
by Phil Abrahams Mon May 08, 2017 2:10 pm

» Trying to reduce the power stroke in my next project
by octavioaugusto.oliveira Thu Apr 27, 2017 1:27 pm

» Its good to be back!!
by Juan galeano Tue Apr 25, 2017 9:31 am


    Big draw length crossbow

    Share

    MRobin
    Tinkerer

    If there is a will, there is a way.


    TinkererIf there is a will, there  is a way.

    Posts : 67
    Join date : 2012-09-01
    Age : 27
    Location : Paris, France

    Big draw length crossbow

    Post by MRobin on Sat Sep 01, 2012 3:31 pm

    Hi everyone,

    New here, I'm from France, and have a long-time passion for achery, bows and crossbows though I don't have a lot of equipment. Here's a crossbow I finished some weeks ago, quite heavy one, designed so it can shoot two bows at the same time like penobscot's bows. But for now it has only one, a 50 or 55 lbs plumtree bow with a specially big draw length (22", taken from the back of the bow) which makes it quite efficient.

    As an improvement I want to craft more powerful wooden bows, using yew preferably.
    Currently it shoots a 20 gram aluminium quarrel at 140 fps, with nice accuracy. I think I can double this with a stronger bow, and get even more if I add a second one.





    At full draw (bends too much in the middle) :



    I know this is not scrupulously medieval (dacron string, screws), but I do with what I've got, while trying to get it to look good enough. Will post more pics if you want.
    avatar
    kenh
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!

    Posts : 708
    Join date : 2012-08-03
    Age : 69
    Location : Living Aboard a Sailboat in Fort Myers, FL

    Re: Big draw length crossbow

    Post by kenh on Sat Sep 01, 2012 6:06 pm

    Nice looking bow! Little things like Dacron don't matter...
    avatar
    Todd the archer
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!

    Posts : 581
    Join date : 2010-02-25
    Age : 55
    Location : sellersville,pa.

    Re: Big draw length crossbow

    Post by Todd the archer on Sat Sep 01, 2012 6:09 pm

    Pretty cool, how long is the prod?

    No doubt long draws helps performance (look at what they are doing with modern crossbows) but generally old world crossbows went with short draw/heavy weight set ups. Some are as short as 5".

    Also what release/lock are you using on your crossbow?

    Todd

    MRobin
    Tinkerer

    If there is a will, there is a way.


    TinkererIf there is a will, there  is a way.

    Posts : 67
    Join date : 2012-09-01
    Age : 27
    Location : Paris, France

    Re: Big draw length crossbow

    Post by MRobin on Sun Sep 02, 2012 12:47 am

    The prod is 45" long notch to notch, with a pretty big initial deflex.
    As for the release system, it's very traditionnal, here's a picture from earlier stage :



    I then reduced the ends of the nut and trigger's shafts (Ø5mm to Ø4mm), so they fit into the reinforcement plates, and cannot escape.

    I will probably add a spring to the trigger, it often gets half engaged which is kinda dangerous because then a very little action on the trigger is enough to release.

    This crossbow was designed to hold heavy draw weights, so if I can lay a hand on a leaf spring I will give an attempt at "big weight AND length" haha. But for now it's not likely to exceed 100 or 150 pounds.

    Sponsored content

    Re: Big draw length crossbow

    Post by Sponsored content


      Current date/time is Thu Jun 22, 2017 11:03 pm