Thoughts on sinew on black locust

[bentstick54]

I have a friend working in a piece of thin ringed black locust. It’s 63” TtT, 1-1/4” at widest point of fades. He said it’s 39# @ 27” and has taken a fair amount of set. He’s thinking about heat treating the belly, taking the set out and adding 3 layers of sinew and then rawhide, to raise draw weight.

I’ve never worked with sinew or black locust, but I’m wondering if the sinew will over power the belly, since black locust is prone to fretting anyway?

[Pat B]

First off, IMO 1 1/4" is way too narrow for black locust. Heat treating will help take out the set but that probably should have been done before the tillering went too far along. Adding sinew at this point may also help a little but again IMO it's too little too late and adding rawhide to the mix will just add excess physical weight to an already strained bow. Black locust should be a good candidate for sinew backing but it probably should be part of the original design and not an after thought to try to fix an over already strained bow.
 Unlike hard backings sinew is elastic so it shouldn't necessarily overpower the belly. Usually it's the nut behind the wheel that causes frets in sinew and I know that as a personal fact.    I have terrible luck with black locust and fretting.
 

[bentstick54]

Thanks Pat. I’ll pass the I info on.

[bradsmith2010]

   I have only made one,, but it turned out nice and did not fret,,
I usually agree with Pat,, but i think the sinew would add some weight,, even though its a bit narrow,, Im just thinking out loud here,, i would be really gentle with the heating to take out the set and not get carried away,,
  depending on the draw he wants, the bow could go shorter with the sinew,,making it more likely to gain weight,, and making the ratio of width to length better,,
   Pat may be right on ,, I am only guessing,, If I wasnt happy with the bow,, nothing to loose,, I would try it,, if the bow does turn out,, you can decide about the rawhide or not,,,sometimes I paint the back,, which does add protection,,,
   

[PEARL DRUMS]

I learned the most playing around with bows I didn't like and wouldn't have used otherwise.

[Pat B]

I agree with both Brad and Pearlie about this. But...for someone not familiar with different woods or methods a 63"x1 1/4" locust bow IMO doesn't fit in the parameters of a successful bow build. And, trying to save an already over strained bow could give false hope to a newer bow builder. If he just wants to experiment with heat treating and/or sinew backing then this bow would be a good choice instead of ruining an a perfectly good stave. We all know about sows ears and silk purses. That was my point.

[Mo_coon-catcher]

With black locusts propensity to fret not long after it takes set (Atleast what I’ve worked) I would be afraid of the collapsed wood ripping apart when the set is pulled out between heat treat and sinew backing. I’ve had sinew rip apart wood that hadn’t been stressed past bracing. Now that was Eastern red cedar. If the limbs has any fretting I wouldn’t mess with sinew backing since I feel it’ll be a waste of sinew.

Otherwise I feel that sinew and black locust will be a good combo. Black locust has good compression resistance, forcing the sinew to stretch and work more. Especially once the black locust is heat treated.

Kyle

[bentstick54]

Thanks guys. Last I heard he has decided to leave it as it. He realized after he did it he should have left it wider, but he’s the type that jumps in before doing any research lol. Sometimes he just gets ahead of himself.

[bradsmith2010]

good points,,,maybe sinew backing without trying to heat it,, would have been a safer option,, and it may have shot ok,, but I have noticed that for a sinew bow to shoot very well I need some reflex,, that being said, best to him on his next bow,,,

[M2A]

Lots of good points i'd agree with here. Compressed stressed locust does not like to forced into tension, Have proved that more than once. I dont like thin ringed locust, it has seemed to crystal easier than thicker ringed stuff. That said maybe your friend has not narrowed the handle yet and could make it a bendy, good dimensions for that. But I suppose its too late for that.  Otherwise i'd agree with it not having enough mass for what is being asked of it. hope to get the finish on a new build soon, 1 3/4 out the fades and 65" ntn for a 27"draw. That is pushing the limits for me with locust handled bow.
Mike     

[Pat B]

Mike, that design for locust sounds about right to me also.