Tree of Heaven Experiment

[lostarrow]

Just thought I would share. Tree of heaven experiment.57" NTN . 2-1/2" at the fades 1-1/4 at the tips . Even taper,slightly bendy handle to minimise stress .Tiller looked good on the long string, never pulled past 60 lbs. Just pulled past  brace height and then a bit. Light heat treating and slightly flipped tips.Left for a couple days(70% humidity around here right now). Exercised about 30-40 times after heat treating before stringing with a low brace height.Everything looked good as I was working it in just past what brace height would be by a couple of inches not more than 50 lbs. at this draw. I attempted to string it (with a long string on the nocks as a stringer to be sure not to introduce undo strain)And it failed in the most pathetic way.IMHO, the grain is too short,not intertwined, the cells themselves are too large(Grows too fast)  . I don't think you can make a decent hunting weight bow without being of ridiculous proportion from this  species. It's too bad really , as it grows so beautifully straight with no knots. Someone  please prove me wrong as I have one more nice straight log of it in the corner and it really shows nice fleck when the wood is quartered. By the way , the fumes from heat treating would best be vented outdoors as the little bit I did made me quite nauseous. Never got really sick but I wouldn't try again.

[dwardo]

Looks like a plain old tension break, doesn't look too dry, rotten or any problems at all. 

[Pappy]

How old was the wood ? How had it been cared for ?
Looks like dry rot to me jmo.
   Pappy

[SLIMBOB]

Agree with Pappy.  Looks like dry rot to me.

[lostarrow]

Yeah I know it looks like dry rot ,but I don't think it was. The wood itself is more like a plant than tree. It was about thirty feet high,maybe less and had four growth rings on the stump . Roughed out right away and sealed with shelac on the back. No signs of deterioration . Stood in the corner of the shop for about 6 months. If you look at the one picture ,the wood has huge pores throughout. I don't think it could handle the extra stress of heating.Just too week in tension. I have another stave  I may try again when I have more time to fart around. Of course I'll post the results. I can start way longer and just as wide ,with a lower weight and work it down from there to see what it can do .

[TBod]

Is it cut in spring. Looks like it, I mean the pores close to the backs surface. Maybe a reason?

[lostarrow]

Cut in Spring. Could be the problem . I'm just thinking I live in the land of bow wood, so I'm not going to go too far out of my way to try to make a bow out of something that doesn't want to participate.Just an experiment. I'll try one more to be fair.

[rossfactor]

I don't see dry rot.  This is a really low density wood, which is also probably weak in tension.  Not a good candidate for bow wood IMHO. Pine grows pretty straight to but... I believe that Good Design can only get you so far.  If a wood isn't suited to bend, it isn't suited to bend.

Gabe

[druid]

I had totaly different results.
http://www.primitivearcher.com/smf/index.php/topic,28922.0.html

[lostarrow]

Hey Druid , I checked out your link. The bow you show has a brown belly. Did you stain it? The wood I have is a pale yellow,medium density (like soft maple or willow) It has visible rays like cherry or poplar,not very big. No visible heartwood. As I said ,there were only about four rings on a four inch tree.Large Pith. The one thing you mentioned was one thing I was thinking as well. Heat treating it overpowered the tension weak back. It was bending not bad before I did it . a little spongy , but bending.I know you can make a bow out of just about anything if it's long enough but I'm curious about the longevity of such a bow. Is yours still shooting?