The Arbalist Guild

Would you like to react to this message? Create an account in a few clicks or log in to continue.

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

Latest topics

» starting a 1400's replica
by tghsmith Today at 1:45 pm

» replacement for baleen?
by tghsmith Mon Jan 17, 2022 1:30 pm

» Josef alm in English
by stuckinthemud1 Fri Jan 14, 2022 7:07 pm

» Medieval crossbow finished
by stuckinthemud1 Wed Jan 12, 2022 7:05 pm

» Trigger mechanisms
by stuckinthemud1 Mon Jan 03, 2022 2:23 pm

» Finish wooden stock
by stuckinthemud1 Sat Dec 25, 2021 1:06 pm

» finish prod binding
by kenh Tue Nov 30, 2021 9:26 am

» What bolts do you use?
by hullutiedemies Mon Nov 22, 2021 1:43 pm

» reinforcement Pin
by stuckinthemud1 Sat Nov 20, 2021 3:40 pm

» Ball shooting Crossbows worth the bother
by Gnome Thu Nov 18, 2021 9:14 am

» New Medieval just about finished
by Gnome Wed Nov 17, 2021 12:01 am

» 3D file medieval crossbow tiller
by crusader Tue Nov 16, 2021 5:15 pm

» Ancient Crossbow Reproduction 120lb@28"
by stuckinthemud1 Wed Oct 06, 2021 3:41 pm

» Chu Ko Nu - repeating chinese crossbow
by c sitas Fri Sep 24, 2021 11:30 am

» Skew of tiller
by drawknife Fri Aug 27, 2021 12:18 pm

» tiller desgin
by crusader Wed Aug 18, 2021 1:37 pm

» Want to build modern target crossbow
by ora8i Fri Aug 13, 2021 4:20 pm

» How do I tune this
by stuckinthemud1 Sun Jul 25, 2021 6:14 am

» Plans and materials for my first build
by c sitas Sat Jul 03, 2021 10:39 am

» Bolt rest
by stuckinthemud1 Mon Jun 14, 2021 6:24 pm

» Collotiere a Charavines crossbow
by stuckinthemud1 Sun Jun 06, 2021 5:25 pm

» ash lath and pin-lock crossbow
by stuckinthemud1 Wed Jun 02, 2021 10:56 am

» Late medieval tournament distances?
by stuckinthemud1 Thu Apr 15, 2021 11:20 am

» Cutting delrin straight by hand?
by kenh Thu Apr 01, 2021 11:24 pm

» Other forums like this one?
by stuckinthemud1 Tue Mar 30, 2021 12:23 pm


4 posters

    Draw stroke limit of a prod

    War Song
    War Song
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 31
    Join date : 2013-11-20

    Draw stroke limit of a prod Empty Draw stroke limit of a prod

    Post by War Song Sun Dec 01, 2013 2:49 am

    Are there ways to determine reasonably, the maximum stroke that you can safely operate and draw a prod back?

     I have a 28 inch loose laminate prod made from tension bars, I can't really tell if its stacking at the 9 inch stroke point, or if my muscles are just wussing out. I was really hoping for more of 10-11 inch power stroke, but afraid that might be near the limit of my prod. At 9 inches, its drawing at about 70-80 pounds.

    Suggestions?


    EDIT: I do not know why the title was "target shoting x-bow", sorry about the mislabeling. Brain is dying on me in old age.


    Last edited by War Song on Wed Dec 04, 2013 1:18 am; edited 1 time in total
    Loosenuts
    Loosenuts
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 7
    Join date : 2013-12-03

    Draw stroke limit of a prod Empty I delete and starts a new thread

    Post by Loosenuts Tue Dec 03, 2013 7:35 am

    I delete and starts a new thread.


    Last edited by Loosenuts on Tue Dec 03, 2013 11:59 am; edited 1 time in total
    avatar
    kenh
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!


    Posts : 851
    Join date : 2012-08-03
    Age : 73
    Location : Living Aboard a Sailboat in Fort Myers, FL

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by kenh Tue Dec 03, 2013 10:02 am

    Loosenuts -- Birch makes a great tiller, and it looks like you're doing good work.

    IMHO, however, it would be better for all of us if your post you work in it's own thread, rather than dumping it into War Song's thread about prod draw limits and strength...
    avatar
    kenh
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!


    Posts : 851
    Join date : 2012-08-03
    Age : 73
    Location : Living Aboard a Sailboat in Fort Myers, FL

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by kenh Tue Dec 03, 2013 10:09 am

    WarSong;  You can certainly draw more than 9 inches! 

    The loose lam tension bar prod in my Avatar pic is two lams -28" and 16" - and draws well over 200# at 13".  Bare handed I can draw it maybe 9"-10", but I need a wippe or other booster to go the distance.  If you can draw it, that prod should be able to go to 14" (half it's length).
    Loosenuts
    Loosenuts
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 7
    Join date : 2013-12-03

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by Loosenuts Tue Dec 03, 2013 11:57 am

    kenh wrote:Loosenuts -- Birch makes a great tiller, and it looks like you're doing good work.

    IMHO, however, it would be better for all of us if your post you work in it's own thread, rather than dumping it into War Song's thread about prod draw limits and strength...
    Thats so strange? I started a new topic. I dont know how it could be? How can War song have the same title? Now i got two topics with the same title ??? 

    Can a moderator delete my post here?
    avatar
    Rizzar
    Workshop Savvy

    Did you see my tool collection?


    Workshop SavvyDid you see my tool collection?


    Posts : 194
    Join date : 2012-08-11
    Location : Germany

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by Rizzar Tue Dec 03, 2013 1:46 pm

    I was trying to reply on this topic yesterday or the day before when I could not find it anymore.
    But when Loosenuts made his thread It was youst there again but unter the new title.
    Obviously some kind of Bug.


    In general it is really hard to say anything about your prod.
    You didn´t give enough information on it.

    One needs to know the measurements of the laminates, the number and length of each resulting in its alignment.

    Besides in my opinion a loose laminate prod is very hard to calculate, so you should hope to get with the above mentioned information to somebody who built a similar one.


    Concerning the alignment, those laminates can be layered together to result in an even bending or, when done wrong, with stiff areas resulting in an uneven bow with changed power draw.


    90# would be similar to a very lightweight wood prod, so relatively low.



    Rizzar
    Loosenuts
    Loosenuts
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 7
    Join date : 2013-12-03

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by Loosenuts Tue Dec 03, 2013 2:06 pm

    Thanks Rizzar. I thougt it was me or we haved the same topic title.
    War Song
    War Song
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 31
    Join date : 2013-11-20

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by War Song Wed Dec 04, 2013 1:33 am

    Maybe I copy and pasted Loosenut's title by accident? Well I fixed the title, sorry about that Loose.


    Kenh, thanks for replying! Your tension bar build was really great stuff, saved me having to tiller an oak board (which I definitely do not have the patient for Rolling Eyes ). Can't believe they had these things just lying around at Home Depot, seems wasted on fences...

    In anycase, I based my prod on yours, except I could only find the 1/2 inch ones. No problem, I cut a pair of 28 inch and 24 inch bar, taped long to short, then taped both of them side-by-side to form a wider prod. I know one 28/24 prod pulled 58 pounds at 11 inch, so two of them ought to give me ~120 pounds at 12 inch.

    If your drawing at 13 inches with the same prod length, I'm guessing I won't have to worry about the prods snapping and hitting me in the face, right? smack
    avatar
    kenh
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!


    Posts : 851
    Join date : 2012-08-03
    Age : 73
    Location : Living Aboard a Sailboat in Fort Myers, FL

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by kenh Wed Dec 04, 2013 10:09 am

    Your bars are 1/2" x 1/4"?  I think that, rather than stack two prods one atop the other to make it 1" x 1/4", I would have gone the other way -- 2, 28s, then 2, 24s, 2, 16s etc.  leaving the prod 1/2" wide and say 3/4 or 1" from back to belly.  This was very common in Chinese prods where they might layer a dozen bamboo lams together. and the prod was deeper than wide.  Take a look at the illustrations in this Chinese Crossbow manual.  The drawing are accurate -- the prod slots are deeper than they are wide: 
    http://www.atarn.net/images/ming_xbow/ming_xbow.htm
    War Song
    War Song
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 31
    Join date : 2013-11-20

    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by War Song Thu Dec 05, 2013 8:46 pm

    The first prod I had already laminated together, but the draw weight was too small, so I made an identical one and mounted them side-by-side them together. Also, I figure friction on the laminates would be lower on a side by side design than with a very deep multi-laminate prod.

    Draw stroke limit of a prod 20131205_1747111_zpsac7313b0
    Draw stroke limit of a prod 20131205_1747271_zps88451935

    Progress so far, just missing the rails and full tickler. 9 inch stroke, anymore and I can't hand draw it. On top of that, I'm using a wooden nut; risky I know, but I lack metal working tools and it happens to be a circular cut of support timber my father had drill out from the basement - too tempting for the improviser in me to pass.

    It seems strong enough, my chiesel could hardly dent it when cutting the bolt slot. Might cast a proper nut from aluminum once I get a furnace running in the spring.

    Sponsored content


    Draw stroke limit of a prod Empty Re: Draw stroke limit of a prod

    Post by Sponsored content


      Current date/time is Wed Jan 26, 2022 3:12 pm