help me tiller this juniper bow

[jeffp51]

I have this juniper stave, which I sinew backed.  As I have been working it down, I have noticed that the reflex has been increasing some.  On the long string both limbs look relatively even. At this point (shown in the pics,) I normally go to a tillering string just short enough to be tight from knock to knock.  That isn't working with this bow with all of the reflex in it.  So I tried to skip a step and go to a lowish brace.  But when I did this, about 70 percent of the flexing came from just one limb.  (Was so afraid for the bow, that I didn't take time to take a picture and got it unbraced as soon as I could.  What gives?

[JoJoDapyro]

What is low brace? What limb is doing the work at low brace? How far do you have it bending on the long string? If you can bend it past low brace it should be fine. Is the sinew the same thickness on both limbs?

[bradsmith2010]

it means that one limb is flexing more,, it did not show on the long string, that can be normal with sinew back,,,take more wood off the limb not working and brace again to see if it is more even,, ,when you brace it and it looks pretty even,, tiller from there,, sometimes with a sinew bow,, when you remove wood it takes longer to show,, than a self bow,, go very slow,,,

[jeffp51]

Once this bow started bending, it lost weight quickly--and most of the reflex pulled out--I suspect the two events were related.  This is my first sinew bow.  I am already below my target weight. Tell what you think now

[russell]

First let me say that I don't have any experience with staves or sinew - yet  .  All I can tell you is what my eyes see.  That bottom limb looks weak in the middle - not quite a hinge, but a little weak.  The top limb looks pretty good. You may have to take a little wood off the bottom limb to get a more even tiller.

You say you're under your target draw weight - just chalk it up to experience and enjoy a light shooting bow.  Some guys with more experience than me may be able to tell you how to gain some draw weight back.  Good luck 

Mark

[crooketarrow]

 I have put sinew on 8 or 10 bows.

  Simple either your tillering really sucks or there's only two more things.

  Either your sinew was'nt dry. LIKELY

  Or the glue you used has given lose. Could be why you lower limbs weaker. I've had this happen twice just not as bad as yours.

  The reflexing was the sinew drying. You bent the limbs before the sinew was dry.

 Only way of really fixing it is strip off the sinew. Add enough sinew again to where your over weight that you want (need) so you can retiller the bow.

 Lot work trash it build another bow.

[bradsmith2010]

even the tiller and you will have a bow also you might weigh the sinew next time before you apply it,, if it is not enough,, it will not hold reflex,,, if you know how much you put on,, you can increase the amount next time,, I think you did great for your first bow,,, sinew bows can trick you pretty easy ,, they feel so heavy first brace,, easy to miss the weight,, you can cut the tips shorter and get more weight,, but you might loose performance if you are cutting off the recurve,,even though the weight is going up,, if the tips are not in front of the handle ,, or the bow is not holding any reflex,, it might not have the cast you want,, but it will still shoot well,,

[jeffp51]

Well, it's no bow of the month,  but I am not ready to scrap it yet, either.  What happens if you heat the belly of a sinewed bow?  It is still over 40#, so I may also leave it.

[bradsmith2010]

tie on some temporary nocks a little below your nocks,, if the weight is good and shoots good then you can make a decision about making the bow a little shorter,, leaving it is also a good option if it is shooting well for you,, I dont think heating the belly of a sinew bow is a good idea

[duke3192]

Mark your weak spots, reflex the bow backwards, put on more sinew and pay attention to the weak spots, leave it reflexed and put in a cool dry place for a month at the least. Too much of the advice you are getting is for self bows, sinew is entirely different and takes longer. When you start stringing the bow, go slow and teach the limbs to bend, the draw weight can change in the process.

[Chief RID]

Great thread! I will be watching.

[bradsmith2010]

if you even the tiller there wont be any weak spots,,

[jeffp51]

I appreciate the help from everyone.  I am still learning to see.  This is what I think is happening: the last bow I did bent badly at the fades to begin with.  I think I over-corrected here.  the first third, especially on the right (top) is stiff.  The left (bottom has a bit of hinge just before the recurve.  The recurves are pulling out too much and making the tips look stiff. Some of the reflex is gone, but still in decent shape. What do the experts see? 

[jeffp51]

Either this stick is so far off, no-one wants to say anything, or it is just wonky enough that no one knows what to say, or I have broken some PA taboo that I am unaware of--but I am a little surprised at the lack of comments. I would like to clean up the tiller a bit before I decide where to go from there, but I don't trust my own opinion at the moment. What are others seeing in this bow?

[Oglala Bowyer]

Just seen your post, but I would say take a few scrapes off the upper third bottom limb to even out the tiller and avoid the hinge area.