Both limbs broke simultaneously

[Bryce]

This is just my opinion, but it just looks like since it broke in such a small section that it’s just a simple tillering error. And when a limb snaps it causes the other limb to fly past brace and center, into a sort of shock and often times break at its weakest point(but not always)
Grab another stick and go again!

[simk]

Bryce: Could be - OK i brought it to brace direct from floortiller - no long string - but then it looked very even and nice and also the brace-height was completly even both limbs - i checked that. Maybe yew is less forgiving to tillerfaults than other wood? The suspected hinge was at the FO not where it broke. And thanx for the explanation why they broke simultaneously.
FilipT: Could be. This one i dried in the living room to speed up.
JN: But still it makes sense. If wood is too dry, it's not good (bad) Heat treat certainly drys out the wood...thats what we know.
DC: It was my first yew chasing a ring - practiced the first 20 rings 
Cheers

[DC]

Leave the bark on. When you're floor tillering the bark will pop off as you bend it. There's your back, nice and pristine.

[Del the cat]

Badger: Why not heat treating yew?
Del: The sapwood was good, no signs of rot or fungus.
You do heat treat yew? I did it to correct a little deflex in the stave and to improve the string alignement...is this generally ok with yew in your opinion? 
You also already mentioned lately here in the forum, that you do some kind of protection whilst heat treating to prevent the heat leaking to the back...i didnt. How exactly do you do this? Are 6 sap rings enough with yew?
Thanx

I clamp thin slats of wood to the side of the bow. I often also put masking tape on the back and sides.
The pic shows what I mean.
Also this you tube video shows how the heat gets channelled along the belly giving a more even heat and speeding the process a tad (mind it is still a slow job).
https://www.youtube.com/watch?v=kM1_A2A0_TI
Del

[Hamish]

 
You have lots of pin knots on the back and it looks like you have ignored them and not compensated for them with extra width. Some people get away with them if the bow is a little longer or wider than necessary(not a good plan for success though )Add to that
the heat treatment and lack of rehydration time, a break was always on the cards. .

[High-Desert]

It could have been the heat treating, but I've never had one brake from not waiting. But this random explosion is something yew does. No signs, no warning, just boom. I had one break after shooting it quite a bit. One morning, I Went to go string it, and without even drawing it, it blew up at brace before being shot. I still don't understand.