Reflex bracing problems

[sieddy]

Hi guys I'm working on a massively reflexed Yew stave (it seems like great wood really dense and elastic!) and I'm having big problems trying to brace it. It's definitely ready for a low brace but everytime I manage to get it braced the string whips round in the nocks so that it's strung in reverse. (the string goes from nock to nock above the back of the stave- hope that makes sense!
I did think to make the loop on the string smaller but then I will struggle to get it on and off the nock. Anybody got any ideas as to how I should progress? Thanks as always. Simon 

[simson]

I assume you have the right length of the string for brace height.

Use a ff string not B50, too much creep and stretch here
Exercise the limbs enough before bracing
When still problems, use a tiiler stick clamped in between pivot point and string. use hook for say a 10" drawlength. Now controll your limbs. When uneven quick unbrace and work on. Repeat ...

[WillS]

Very often with large amounts of reflex you need to be a bit ballsy and forget low brace.  Get confident in the tiller shape, and brace it almost at full height.  Otherwise you'll be fighting the reflex forever.  Same with heavy bows - low brace just stretches out due to the immense force acting along the string, rather than bringing the tips inwards together. 

Following the book and doing every stage you read about is fine for the basic board bow or light to medium weight straight stave bow, but once you have lots of weight or reflex you need to adopt a more... Improvised approach.

[sieddy]

Hi Simon. I'm pretty sure I've got the right length of string for the brace it's just an inch or so short of the Bows length. I haven't got any fast flight so will persevere with the B50 for now.
The limbs are moving quite smoothly now but there is still a good bit of strength in them.
I will your suggestion of clamping the roughed out bow onto a pivot point. I think that will help- thanks. 

[sieddy]

Hi Will thanks for this also. I thought that it would help if I braced it higher but was worried about overstressed the limbs. I will maybe try it a bit higher- with a crash helmet on!
Actually the stick looks pretty flexible! 

[Eric Krewson]

I started out have a terrible time stringing high poundage or highly reflexed bows to go to the short string so I added a stringing groove to my bows so I could string them with a parachute cord stringer. This made it a breeze to accomplish that initial stringing.



I always filed away the extra groove as I finished the bow but one day decided to leave it. Now I have an extra groove on the top limb and and one wide groove on the bottom limb to allow the stringer to fit over the bow string.

I think my current tips look pretty good with the extra groove.

[sieddy]

Hi Eric thanks for the advice. I agree those tips look ace!

[bradsmith2010]

that extra string groove looks great,, when I am working on a heavy or reflexed bow,, I tie a leather nock below the real nock,,
I put the long string on the leather nocks and pull the bow so I can brace it,,,as suggested,, if highly reflexed,, it will stretch the string and reverse if you are not careful,,, I hold the bow for a few minutes with the long string and braced,, if it seems like its gong to go crazy,, I unstring,, let it down and twist the string a little shorter,, finally twisting the string and no stretch left it will stay braced,,, that is when I let it stay braced for a while to calm it down a bit,,   I can usually take off the leather nocks and get it strung after tillering just a bit,, I like the extra string grooves as well,,,,

[bubbles]

An inch shorter than the bows length seems a bit too long for B50 on a highly reflexed bow.  B50 stretches a lot unless it is a very over built string. Try making it shorter in increments until it stays.

[sieddy]

Bubbles thanks for your input it's really helpful.
I've shortened the string but i'm still having a helluva time with this stick though. It's bending nicely (maybe 15") and isn't too heavy (hopefully it'll end around 50# @27"). But everytime I brace it the handle area springs back past the string and I've got a reverse braced situation (it has a nice profile actually! :-)
I'm going to try shaping the tips properly and making a proper string for it. Hopefully that will hold it in brace.

[bushboy]

It's really a worth while investment to get some ff material if building heavy and highly reflexed models.ive seen b55 stretch about 3" at first brace then reverse like yours.not the best in that the string has. To be shortened placing more stress than needed to brace because the bow has to be bent farther to be strung.i also use the step thru method (not universally accepted)so I find it easier to go over the top instead of slipping the string up unless the loops are quite large.

[sieddy]

Hi Bushboy thanks fer the tip. I am reluctant to buy fast flight string material when I have a roll of B50 sat there not earning it's keep. But I will certainly give it a try if the problem persists (which is looking likely!)

[dbb]

Regarding the string..If you gonna use dacron (B-50 or 55)make sure there is no more than nessecery twist in it and pre-stretch the crap out of it first.

[Badger]

       As far as I am concerned b 50 has no place when it comes to first braces. You need to have control over your bow here. B 50 requires way too much over bend to brace and have a decent brace height.

     I have what I call a manual bow press, just a couple of 4" wide wheels on an adjustable track for bow length. They sit up about 16" and all I do is puch the bow against the wheel to brace it. I have a lot of control because I can let it up slowly onto the string or remove it again if neccessary.

[sieddy]

Hi guys thanks for your tuppence worth! (it's the English 5 cent! )
Badger your set up sounds awesome!
I'm amazed to hear everybodys views about Dacron, I never realised it was such stretchy stuff and so unsuited to my purpose. Would I be better off with a (slightly overbuilt) linen string? I'm under the impression that Linen doesn't stretch much much?
Anyway the stick is progressing nicely I'm hopeful that I'll bring the project home!