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

» Troubleshooting
by Cscott Tue Nov 15, 2022 11:55 am

» Fiberglass H-bows
by c sitas Sat Nov 12, 2022 8:44 am

» Bad Antler
by drawknife Sat Nov 12, 2022 3:48 am

» Anyone make their own bolts?
by Juniper Mon Oct 17, 2022 8:20 am

» Colletiere a Charavines crossbow
by stuckinthemud1 Sun Oct 16, 2022 3:39 pm

» Josef alm in English
by Juniper Sat Oct 15, 2022 4:22 am

» Qin/Han lock drawings
by kenh Fri Sep 23, 2022 8:16 pm

» stirrup dimensions?
by stuckinthemud1 Thu Sep 01, 2022 1:49 pm

» Skane/Lillohus lockbow information needed
by stuckinthemud1 Sun Aug 14, 2022 6:23 am

» need help contacting le musee Dauphinois Grenoble
by stuckinthemud1 Sat Aug 13, 2022 3:22 pm

» Low Draw Weight Build
by stuckinthemud1 Fri Aug 12, 2022 3:09 pm

» Trigger testing Rig/Jig?
by ora8i Fri Aug 12, 2022 1:13 pm

» best type of horn to use..
by stuckinthemud1 Fri Jun 24, 2022 6:13 am

» Han Dynasty Chinese Crossbow
by hullutiedemies Fri Jun 17, 2022 1:00 pm

» Drawing of Crossbow
by stuckinthemud1 Fri Jun 03, 2022 3:01 am

» "How To Make Everything": Early Crossbow
by stuckinthemud1 Thu Jun 02, 2022 3:41 am

» Black inlay
by stuckinthemud1 Fri May 13, 2022 3:18 pm

» Roller nut details
by drawknife Thu Apr 21, 2022 2:44 pm

» 330#/7" wood bow
by Anatine Duo Tue Mar 29, 2022 11:08 am

» starting a 1400's replica
by stuckinthemud1 Thu Feb 24, 2022 1:26 pm

» 18th century German crossbow reproduction
by Fangbows Sun Feb 20, 2022 7:15 am

» replacement for baleen?
by tghsmith Mon Jan 17, 2022 9:30 am

» Medieval crossbow finished
by stuckinthemud1 Wed Jan 12, 2022 3:05 pm

» Trigger mechanisms
by stuckinthemud1 Mon Jan 03, 2022 10:23 am

» Finish wooden stock
by stuckinthemud1 Sat Dec 25, 2021 9:06 am


5 posters

    brace height and draw length for fibreglass bow

    backgardenbowyer
    backgardenbowyer
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 27
    Join date : 2013-01-13
    Location : London

    brace height and draw length for fibreglass bow Empty brace height and draw length for fibreglass bow

    Post by backgardenbowyer Sat Feb 09, 2013 6:18 am

    I'm just assembling the materials and tools for my second build - a modified medieval style using a fibre glass prod. Got a nice piece of oak, some 36mm delrin (matching forstner bit), 10mm square for the tickler is on the way. The fiber glass prod I have is marked 150lbs wit hthe trade name "Armex" and is about 27" long. I've braced it with a tillering string to about 3.25" (from the belly) and this looks about right to my longbowyer's eye. I have, however, no indication of the draw length or power stroke - any suggestions?

    My bow scales only go up to 90lbs and as far as I can tell the bow is reaching 100lbs at about 10" draw (from belly), or a power stroke of 6.75". A weight of about 125lbs will be enough for my purposes. I was thinking of going back to 12" draw and a power stroke of 8.75". Does that sound about right? Obviously once I drill the nut hole I am committed so thought it best to get some advice first!

    Thanks so much for your help to a beginner.
    stoneagebowyer
    stoneagebowyer
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!


    Posts : 490
    Join date : 2011-01-12

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by stoneagebowyer Sat Feb 09, 2013 8:02 am

    I cant off the top of my head think of the formula for calculating bow weight at a given draw, though on Primitive Archer website, you may find that answer. If you have a tillering stick and a bathroom scale, you can at least get a rough idea of weight at a given draw length.
    Dane
    Geezer
    Geezer
    Master Crossbowyer
    Master Crossbowyer


    Posts : 1194
    Join date : 2010-01-12
    Age : 74
    Location : Austin, Texas, USA

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by Geezer Sat Feb 09, 2013 8:37 am

    For Backgardenbowyer, re this:
    "The fiber glass prod I have is marked 150lbs wit hthe trade name
    "Armex" and is about 27" long. I've braced it with a tillering string
    to about 3.25""
    Your glass prod sounds suspiciously like one of the many knockoffs from the old Barnett Panther. Their glass prods are approx 1 inch wide and 27-28 inches long. They're designed to work from a brace @ 3 inches and a draw of perhaps 8.5 from there. Just off the top of my bald-head, I'd say you should be reasonably safe putting the lock 12 inches behind the belly (inside surface) of the prod. Just my two-bits. Geezer.
    Todd the archer
    Todd the archer
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!


    Posts : 581
    Join date : 2010-02-25
    Age : 60
    Location : sellersville,pa.

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by Todd the archer Sat Feb 09, 2013 8:56 am

    Made one with a similar prod it. It is set up with a total draw of 13 3/8" from inside prod to the nut, and 10 1/2" from brace to nut (powerstroke). Have shot a couple dozen times so far no problems. Guessing it is close to 150 pounds.

    I am thinking your set up will be fine.

    brace height and draw length for fibreglass bow 100_9591_zps15ff04a6

    Todd
    backgardenbowyer
    backgardenbowyer
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 27
    Join date : 2013-01-13
    Location : London

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by backgardenbowyer Sat Feb 09, 2013 10:14 am

    Thank you guys. Done a bit more research and I think this might be the same prod as found on the model sold here as an Armex "Jaguar" here which seems to have a power stroke of 10" (though one site said 16" which is clearly the bolt length.)I'll go for a power stroke of about 9", maybe a tad more.

    Todd - I like you bow: interesting way the prod is attached to the tiller: are the some wedges in the slot for the prod? It looks like less hassle than a bridle.

    I'll let you know how I get on.
    Todd the archer
    Todd the archer
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!


    Posts : 581
    Join date : 2010-02-25
    Age : 60
    Location : sellersville,pa.

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by Todd the archer Sat Feb 09, 2013 10:35 am

    Yes there are wedges in front of the prod which are held in place by the sides of the stirrup. I have come to prefer this method. Simple and secure and easy to change out.

    Todd
    Taxus
    Taxus
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 40
    Join date : 2012-10-31
    Location : England

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by Taxus Mon Feb 11, 2013 5:45 am

    backgardenbowyer: I have an Armex crossbow with the same 150lb fiberglass bow you've bought. You might find the dimensions of this bow useful for you own.
    Brace height is 3 inches
    Draw length/powerstroke is 10 1/2 inches (exactly 27cm)


    Last edited by Taxus on Mon Feb 11, 2013 5:45 am; edited 1 time in total (Reason for editing : correction)
    backgardenbowyer
    backgardenbowyer
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 27
    Join date : 2013-01-13
    Location : London

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by backgardenbowyer Tue Feb 12, 2013 12:25 pm

    Thanks Taxus, I roughed out the tiller on Sunday, and have drilled the nut socket and rough cut the bow slot. There is a little over 12" from the belly to the centre of the nut - so a power stroke of 9"with a 3" brace. I estimate weight to be around 120lbs at this point and the bow feels to be stacking here. I've only drawn the bow by putting my foot on it and and 12" total draw is as much as I can manage. Maybe it will feel easier on the stock with a stirrup. Hopefully it will be enough for my purposes.

    10mm square bar for the tickler arrived today, with a small vice and a light bench it's going to be a bit of a challenge to bend cold, but facing new problems are the fun part of a new build!
    Taxus
    Taxus
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows


    Posts : 40
    Join date : 2012-10-31
    Location : England

    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by Taxus Tue Feb 12, 2013 3:17 pm

    Sounds like your making good progress.

    A technique I use to make cold bending easier (especially with a small vice) is to use a hollow, round or square metal rod, the longer the easier it will be.
    You slide this over the trigger which is held in the vice and use the rod as a lever to bend the 10mm bar.
    Its is possible to put twists in this way but they can be undone by bending in the opposite direction.

    Sponsored content


    brace height and draw length for fibreglass bow Empty Re: brace height and draw length for fibreglass bow

    Post by Sponsored content


      Current date/time is Thu Dec 01, 2022 8:47 pm