It BROKE. WHY?

[Watsonjay]

So I was bending some reflex into the tips of my osage takedown. A few things happened. The top part of the form I had the tip wedged into broke of so I had to clamp it back on and reheat, then that clamp came off and I switched clamps and reheated.  Crack!!  So I am thinking these are my mistakes: heated too many times with dry heat. Didn’t use oil. Maybe left the wood too thick?  Any other suggestions for a rookie bowyer. Maybe next time use steam(but it is so hot in my shop in Florida).

[Watsonjay]

I was going for static reflex. Do you think it is repairable with a tip laminate?

[KenH]

Personally it looks as though your 'turning radius' was too small for the thickness of the wood.  You wouldn't try to bend a 90 or even a 45 degree turn in 1/4" PVC in that sort of radius.  I would have built it with siyahs rather than trying that kind of bend.   

At the very least I'd have test-bent a length of the same wood and dimensions as many times as it took to get it right before risking the bow I'd put a lot of work into... .

[Watsonjay]

It really wasn’t that sharp of a bend. It is the form I have used several times just on thinner wood. Here is the other end that worked fine

[simk]

Yes, there's a direct correlation between thickness and possible bending radius. that kind of bend is no problem if done correctly: only make it a little thicker than your final thickness  estimated.. in the bending section treat the belly as if it was the holy back of the bow: work to one continous ring, sand it, sligthly round the edges, no toolmarks, then: 1 boil (safest method, can't fail) or 2 steam (ok method if done correctly), 3 dry heat (best for slight corrections but risky method for sharper bends). good thing about dry heat is, it locks the wood and the shape, much less creeping back than steam. it also hardens the wood and gives more springyness. some may disagree but my recipe still is boiling for the bend, then dry heat to set the shape on the caul.
cheers

[Watsonjay]

Next time I’ll boil