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

Latest topics

» Crossbow with built in lever?
by kenh Today at 6:21 am

» Chinese crossbow with auxiliary string?
by stm2010 Mon Jun 26, 2017 9:48 am

» 15th century saxon prods
by Geezer Mon Jun 26, 2017 7:34 am

» Yet another one
by jocky Sun Jun 25, 2017 7:09 am

» Crusader crossbow
by c sitas Thu Jun 22, 2017 9:41 pm

» 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

» 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


    Working with leaf springs

    Share

    Hermit
    Workshop Savvy

    Did you see my tool collection?


    Workshop SavvyDid you see my tool collection?

    Posts : 245
    Join date : 2013-09-10

    Working with leaf springs

    Post by Hermit on Thu Jan 23, 2014 10:39 am

    Many enquiries seem to come in regarding working leaf springs.The first thing to understand,is when you acquire a leaf spring,it is in it's finished condition,for the job it was designed to do.You will be wanting it to do a different job.
                                            In order to alter it to do a different job,you need to first understand how it's made.The spring starts out as a relatively soft piece of steel,it is cut to shape and then bent to the required profile.Once the spring has been cut to shape and bent,it then has to be heat treated(hardened and tempered)heat treatment gives the spring it's "springiness".Leaf springs,once hardened,cannot be bent cold without fracturing or breaking.Leaf springs,like any metal,can be bent using heat.As soon as the spring is bent with heat,it is useless,the temper has been destroyed,and the "springiness" is gone.So how can a leaf spring be worked?.If extensive shaping is required,the spring should be heated and softened(annealed)worked to the required shape,and then re-hardened and tempered.Unless you are an extremely skilled blacksmith,or have access to a highly  sophisticated(and expensive) hardenening and tempering industrial facility,forget it.You can shape,or 'tiller' the bow yourself.The best way to do this would be with an angle grinder.Grinding creates lots of heat,so excessive grinding can destroy the temper,so proceed with caution!Filing I would say,is not an option,filing heat treated steel will dull your file in record time,with little removal of metal.
                      As for using a prod with a hole in the exact centre,Would you try to use a longbow with a hole drilled right through the centre of the handle?
                                               Hermit.

    Rizzar
    Workshop Savvy

    Did you see my tool collection?


    Workshop SavvyDid you see my tool collection?

    Posts : 192
    Join date : 2012-08-11
    Location : Germany

    Re: Working with leaf springs

    Post by Rizzar on Thu Jan 23, 2014 11:14 am

    I totally agree with your points.

    If I had written about it it would have taken me a long time and I would have expressed it more complicated making it harder to follow.
    (which in fact I prepared but was not satisfied with)

    My suggestion for handling the holes still is either
    -stiffening the area with clamp plates
    -grinding the prod so low that there is no hole anymore
    -living with much efficiency loss during lower calculated tension with shorter draw
    -or completely forgetting about leaf springs with center holes cuting them into pieces to forge some beginner knives with the metal.

    btw: Hermit, you´ve got pn!!!

    Rizzar

      Current date/time is Wed Jun 28, 2017 9:44 am