Oh well, it's just a stick, right?

[jeffp51]

It broke right across a funny bump in the wood.  I thought I had violated the ring, so I took the whole back down a ring (they were pretty thin) and I left just a little around this spot just to be sure.  Maybe that is what caused the break--or maybe it was just a weak spot.  May it was just bad bowyering.  Better now than in the hands of my son--who was supposed to get it.

[sleek]

Well it wasnt your tiller. It waz looking nice. Now i have had those little bumps becore and dont know what causes them or what they are. Id be interested in learning more about them myself. Thats one hellova blow out.

[bradsmith2010]

I had a sinew bow blow a few weeks ago,,
I checked the moisture with a meter,, said 6%
I had been keeping it inside where the heater is,,,
I checked the humidity in that room it was at about 30%,,, so I moved my bows to another room that is at about 50% ,,
I think during the winter we forget how low the moisture content can get,,in a heated environment
sorry it blew,, check your relative humidity and make sure thats not part of the problem,,,

[Badger]

  It does look like a serious violation at that bump, I can't see it clearly though.

[jeffp51]

Actually left a little of the previous ring on it - trying to play it safe. It clearly broke over the top of it anyway. Here in Utah the humidity is always low, perhaps that contributed too.

[simson]

I suppose it was the right limb that broke.

1. I don't know, how the bow looked braced and unbraced. But seeing the f/d pic I see it is a very asymmetrical bow (what is doable), this presumes a positive tiller. Don't know if you had.

2. The stick did not sit right on the tree, look where the pivot point is. Left limb is long and bends the same amount as the lower, which is short. You have concentrated the stress in the lower and the position on the tree increase the stress.

3. It is a lot better when working with a tiller tree (I do not like it) let the bow rest in a hanging loop. This allows to balance out and you can see mistakes in tiller early.

4. Avoid long time fulldraw at the tiller tree while taking pics. A lot better: let an assistant do the pics while you draw short time.

[simson]

And yes it sucks, having a blow up.

 Good thing is: wood grows and we can harvest it 

[PEARL DRUMS]

Id you would have left that area about 1/2" wider, it may have lived. No promises. Just an assumption, but I'd say your fades are a bit stiff, add those two together and sh!t happens!

[jeffp51]

One of the contributing factors, was that I took another ring off the back after I started tillering because I was afraid the spot was violated- and because my son, who was helping, put a deep scratch across that same spot- that left the stave weaker and unbalanced for the draw weight. It was just starting to come around when the ticking started. In the future, maybe treating the spot more nock-like will help.

[Springbuck]

Actually left a little of the previous ring on it - trying to play it safe. It clearly broke over the top of it anyway. Here in Utah the humidity is always low, perhaps that contributed too.

YUP.  I almost NEVER have any problem with wood being too wet out here in Utah during spring and summer, and in the winter it can get awfully dry.

Was that a BL bow or what?  The tiller was looking great, but the limbs were quite a lot different lengths, and it seems much of the left side limb was very much LESS strained than the bottom.

[Springbuck]

Also, what do you mean by "nock-like"?

[jeffp51]

I meant knot-like. The bow was Osage. It had a natural reflex on one side- the side that broke- that I tried to copy on the other.  Contrary to both Springbuck and Simon, it was the stiffer left side that broke.

[George Tsoukalas]

Yes, it looks like a knot. Leave it wider and tiller that knot a bit stiffer than the rest of the limb.
That's what I do.
Jawge

[sleek]

I dont know  it is, but i always call the tiger eyes because of the appearance they have. Never had one give me trouble though.

[Joseph]

Looked nice until
*snap*
But great looking bow anyway