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

Latest topics

» Fish skin cover on early hornbow
by stuckinthemud1 Sat Sep 14, 2019 11:14 am

» anyone know anything about this one
by OrienM Sat Sep 14, 2019 10:16 am

» what is nordic/swedish/northern style
by stuckinthemud1 Thu Sep 12, 2019 1:09 pm

» crossbow 17136, Royal Armoury Collection, Sweden
by stuckinthemud1 Sat Sep 07, 2019 1:26 pm

» notch lock trigger mechanism
by banuvatt Sat Sep 07, 2019 12:55 pm

» how made homemade (reverse) crossbow ?
by ali.j Sat Sep 07, 2019 12:08 am

» Metal clamps for bastard string
by Geezer Thu Aug 29, 2019 11:20 am

» Goats foot leaver design
by Geezer Thu Aug 29, 2019 11:17 am

» mounting sideplates
by Geezer Tue Aug 27, 2019 12:01 pm

» Hornbeam Prod
by banuvatt Thu Aug 22, 2019 9:18 am

» Binding a prod in leather?
by Wildtech Wed Aug 21, 2019 9:08 pm

» help with patterns for my 'bow
by stuckinthemud1 Tue Aug 20, 2019 4:23 am

» Steel crossbow prods
by c sitas Mon Aug 19, 2019 9:09 am

» Yew Composite prod:help needed
by stuckinthemud1 Sat Aug 17, 2019 12:10 pm

» appalachian crossbow trigger mechanism
by OrienM Fri Aug 16, 2019 6:29 am

» home-made bolt heads
by OrienM Tue Aug 13, 2019 6:42 pm

» Knottelarmbrüste or other wooden crossbows
by stuckinthemud1 Mon Aug 12, 2019 4:01 pm

» "Cherry Red" case hardening compound?
by Andy. Sun Aug 11, 2019 1:45 am

» can you ID this crossbow?
by stuckinthemud1 Sun Aug 04, 2019 4:04 pm

» Safely un stringing / stringing powerful Medieval replica crossbow
by Geezer Sun Aug 04, 2019 3:09 pm

» crossbow stock shape
by 8fingers Fri Aug 02, 2019 11:05 pm

» How to make a slurbow?
by banuvatt Sun Jul 28, 2019 10:36 am

» installing a tickler
by stuckinthemud1 Sun Jul 28, 2019 9:21 am

» Seal lath bindings, what to use?
by DARIVS ARCHITECTVS Sun Jul 28, 2019 4:54 am

» Compound twinbow pistol (posts vs pulleys)
by c sitas Fri Jul 19, 2019 7:10 pm


    Changing brace height

    avatar
    Frode
    Techno Weeny

    Lets put a laser on it!!!


    Techno WeenyLets put a laser on it!!!

    Posts : 51
    Join date : 2011-03-17
    Location : Indianapolis, IN

    Changing brace height Empty Changing brace height

    Post by Frode on Sun Jan 29, 2012 6:56 pm

    Hello all,
    Pardons if this is covered elsewhere, but I haven't found it. I just got an Alchem steel prod and string to match. According to the web page, it wants a 3 1/2" brace, but when we (it took both Missus Frode and me, and we almost didn't get it done Embarassed) got it strung, it promptly settled to about an inch and a half or two (see below).
    Here's my question. Is raising brace height on a crossbow like a long bow, i.e., twist the string a few times and check again? It's not twisted at all, right now. Or do I have a string problem?
    Thanks,
    Frode
    Changing brace height P1010008_7
    Changing brace height P1010007_12
    Todd the archer
    Todd the archer
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!

    Posts : 581
    Join date : 2010-02-25
    Age : 57
    Location : sellersville,pa.

    Changing brace height Empty Re: Changing brace height

    Post by Todd the archer on Sun Jan 29, 2012 7:31 pm

    You are correct, remove and twist up (twist in the direction the serving is wound).

    Not unusual for a new string to stretch some untill it settles in.



    Of course this is alot of work unless you have a crossbow press. I have got to make me one, one of these days.



    Todd
    avatar
    Frode
    Techno Weeny

    Lets put a laser on it!!!


    Techno WeenyLets put a laser on it!!!

    Posts : 51
    Join date : 2011-03-17
    Location : Indianapolis, IN

    Changing brace height Empty Re: Changing brace height

    Post by Frode on Sun Jan 29, 2012 8:02 pm

    Thanks, Todd! I'm going to need one of those, too.
    Frode
    Gnome
    Gnome
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!

    Posts : 420
    Join date : 2011-10-16
    Age : 55
    Location : North Georgia

    Changing brace height Empty Re: Changing brace height

    Post by Gnome on Sun Jan 29, 2012 8:02 pm

    Did it actually stretch that much, or was it just too long to begin with? I've noticed quite a bit of variation with strings I've gotten from Alchem, I ordered a prod and two strings and the strings didn't match at all. One was fairly thick and fit pretty well, only requiring a couple of twists to get to the proper brace height. the other was about an inch longer and much thinner, so far I've only used it for a bastard string.
    I'd set up a bastard string and clamps and get a cocking rope, if I was you. You can rough cut a 2x4 to tiller dimensions with notches for the prod and string and you can span and unspan your prod to your heart's content without undue stress on the missus.
    avatar
    Frode
    Techno Weeny

    Lets put a laser on it!!!


    Techno WeenyLets put a laser on it!!!

    Posts : 51
    Join date : 2011-03-17
    Location : Indianapolis, IN

    Changing brace height Empty Re: Changing brace height

    Post by Frode on Mon Jan 30, 2012 3:29 pm

    Thanks, Gnome!
    That sounds like the way to go. The notched board is easy enough, the clamps I'll have to mull over a bit, unless there are pictures anywhere.
    Frode
    Sugarbuzz
    Sugarbuzz
    Fresh Blood

    Doesn't mean
    I'm new to crossbows


    Fresh Blood Doesn't meanI'm new to crossbows

    Posts : 23
    Join date : 2011-12-27
    Age : 44
    Location : Washington

    Changing brace height Empty Re: Changing brace height

    Post by Sugarbuzz on Mon Jan 30, 2012 5:10 pm

    I seem to recall reading somewhere about limiting the amount of twists you put into a crossbow string, for safeties sake. Maybe I am mistaking bowstrings, but I'd have sworn that putting too many twists into a string increases its chances of weakening? Maybe someone more seasoned here can shed some light on that? I would say that string looks a bit too long, in my opinion. In my experience it would take a large number of twists to bring it to the proper length. I adhere to a policy of remaking a string if I need to twist it more than 6 times. Just an idea/question I'm tossing out there.
    mac
    mac
    Master Weaponsmith
    Master Weaponsmith

    Posts : 560
    Join date : 2010-12-23
    Location : Near Philly USA

    Changing brace height Empty Re: Changing brace height

    Post by mac on Mon Jan 30, 2012 5:51 pm

    I think it would be safe enough to put as many twists in the string you want, but you will lose performance. The more the string is twisted the stretchier it becomes.

    If you have to put in more than about 4 or 5 full twists, it would be better to make a new string. If nothing else, though, you will be able to find out how long the string should be.

    Mac
    Gnome
    Gnome
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!

    Posts : 420
    Join date : 2011-10-16
    Age : 55
    Location : North Georgia

    Changing brace height Empty Re: Changing brace height

    Post by Gnome on Mon Jan 30, 2012 6:51 pm

    I've gotten away without actual clamps for a bastard string for my steel prod from Alchem, I bent some heavy guage steel wire, about 1/8" thick, to this shape:
    Changing brace height DSCN0046

    Changing brace height DSCN0047
    Sorry so blurry, but you get the idea, I hope. It fits sideways over the tip of the prod, then turns and locks into place in the thinest profile of the prod right inside the nock. I have to pinch and prod the real string a bit to fit inside it but it is pretty secure, especially with the hooks for the bastard string oriented to the outside.
    Oh, and about the "bastard stock"- don't forget some kind of foot stirrup for leverage. A well knotted, sturdy piece of rope will work. It may sound like a lot of trouble to spend all that effort building a dummy tiller, but I've found it handy to be able to string my prods while the real tiller is still in progress, to make sure I'm getting the angle of the prod socket just right.
    mac
    mac
    Master Weaponsmith
    Master Weaponsmith

    Posts : 560
    Join date : 2010-12-23
    Location : Near Philly USA

    Changing brace height Empty Re: Changing brace height

    Post by mac on Mon Jan 30, 2012 9:01 pm

    Gnome,

    Could you show us a picture of these gismos on the prod? I am having trouble understand how they attach.

    Mac
    avatar
    Frode
    Techno Weeny

    Lets put a laser on it!!!


    Techno WeenyLets put a laser on it!!!

    Posts : 51
    Join date : 2011-03-17
    Location : Indianapolis, IN

    Changing brace height Empty Re: Changing brace height

    Post by Frode on Tue Jan 31, 2012 10:32 am

    @Gnome, I think I know, how this works, but like Mac, I would benefit from a photo, if you have one.
    @Everyone/Anyone, How long should a string be? Same formula as a longbow, nock to nock distance minus 3"? Or something else? The string I have now is simply too long.
    Thanks,
    Frode
    mac
    mac
    Master Weaponsmith
    Master Weaponsmith

    Posts : 560
    Join date : 2010-12-23
    Location : Near Philly USA

    Changing brace height Empty Re: Changing brace height

    Post by mac on Tue Jan 31, 2012 11:39 am

    Frode,

    I'm not sure that it is possible to make generalizations about the string length. A lot depends on the amount of recurve, and deflex in the prod.

    Perhaps someone who has worked with these prods can make a specific recommendation.

    Failing that, you would always start by measuring what you have there, and make the new string an inch shorter. That will probably get you a usable string. You can then use the information you gained to decide if you need something different. It will be great practice making strings, and you can hang the ones you don't use up on a nail somewhere in the shop in case you need them later as bastards.

    Or, like I implied earlier; keep adding twists to your current string until the brace height looks good, and then measure the resulting string length. That should get you pretty close to the measurement you need for a new string.

    Mac
    Gnome
    Gnome
    Crossbow Junkie

    I live here!


    Crossbow JunkieI live here!

    Posts : 420
    Join date : 2011-10-16
    Age : 55
    Location : North Georgia

    Changing brace height Empty Re: Changing brace height

    Post by Gnome on Tue Jan 31, 2012 2:43 pm

    Changing brace height DSCN0048
    Changing brace height DSCN0051
    Hope this helps. In this case my bastard string is a 26" from one of my FG prods, twisted pretty extremely to get enough tension, but as you can see, you don't have to flex the prod too far to get enough slack to slip the real string over the tips. One could put a piece of cloth or leather under the "gizmo" to protect the prod from marring and scratches, since I haven't applied a final finish yet I haven't worried about it. The tension on the bastard string and the profile shape of the prod dictate that the hooks are going to stay put.
    mac
    mac
    Master Weaponsmith
    Master Weaponsmith

    Posts : 560
    Join date : 2010-12-23
    Location : Near Philly USA

    Changing brace height Empty Re: Changing brace height

    Post by mac on Tue Jan 31, 2012 5:27 pm

    Thank you, Gnome. It all makes sense now.

    Mac

    Sponsored content

    Changing brace height Empty Re: Changing brace height

    Post by Sponsored content


      Current date/time is Thu Sep 19, 2019 9:13 am