Starting a bamboo belly and backed bow.

[Prarie Bowyer]

Guys I had some questions.

I have a bunch of that "Lyptus" wood left.  I know it dosen't make working limbs well.  But how about using it for a riser?  I'm thinking of one of two designs.  Design one would be a single core piece of bamboo and the belly and back rinds that go from tip to tip and the segment of lyptus stuck inside. 

What I'd realy like to do is somthing more like a Fred Bear Montana with more thiner layers of core and riser stuck between them.  I'm wondering if the Lyptus would hold up to this?  I DOES NOT WORK for working limbs.  It chrysals badly, then it split along the grain layers when I tried to sandwich it before.

Thanks,
PB

[dragonman]

I've never used 'lyptus' wood for a bow, but I know it comes in a large range of hardness's, from quite light to quite heavy, cos it grows round here quite well.   I personally wouldnt use the lighter  stuff between a bamboo back and belly, harder wood works better with boo....some say the core doesnt do much and it doesnt matter , but thats not my experience...
I wonder if the ausralian aborigines made bows from lyptus?

[Prarie Bowyer]

I'm just wondering about the viability of a riser from it.

[dragonman]

I must've missundertood your question.....no reason why it wont work as a riser?

[rossfactor]

Are you talking about Eucalyptus? If so, I'd mention that there are (based ion wikipedia) 734 species of this tree. And some may be excellent for bow making.  Manny made a sweet one back in 08 or something.  You can find it with a search.   Definitely some species are lousy, (a lot of which are the kinds we have growing here in the States) but as a genus, I bet there are some underused 'lyptus that will blow peoples minds as a bow wood. 

Gabe

[Dauntless]

If it splits along the grain lines the shear strength might be too low for a core lam.

[rossfactor]

http://www.primitivearcher.com/smf/index.php?topic=7928.0

and the post

http://www.primitivearcher.com/smf/index.php/topic,7810.0.html

heres a quote

"bowmakers like Graeme know the aussie eucalypts well, some species are as good as or better than osage or yew but the trouble with them is that one tree varies such a lot from another grown just a few yards away, very dependant on growing conditions. I have made a couple of sapling bows that worked OK (to very basic standards) but I am not good at tillering yet."

not my words, but intriguing.

Gabe

[Prarie Bowyer]

I"m gonig to try it.  It's only going to cost me $12.00 in boo rinds.  And the Lyptus whouch might make a good spoke shave body.

[mikekeswick]

I've never used 'lyptus' wood for a bow, but I know it comes in a large range of hardness's, from quite light to quite heavy, cos it grows round here quite well.   I personally wouldnt use the lighter  stuff between a bamboo back and belly, harder wood works better with boo....some say the core doesnt do much and it doesnt matter , but thats not my experience...
I wonder if the ausralian aborigines made bows from lyptus?

The core isn't feeling tension or compression and is doing nothing in that sense but it certainly does feel shear. Hence maple being the choice of core for a long time in many old bows. Glues well and is diffuse porous so it just isn't going to split along earlywood rings because there aren't any!

[Prarie Bowyer]

Oh!

Verry helpful Mikeswick!  So what do you think of using the lyptus for a riser?  I'd think shear would be minimal in that region pluss I'll be sandwiching it either bamboo or maple.

[DarkSoul]

You could basically use any wood with an SG over 0.5 in my opinion. As Mike explained, there not a lot of forces on a core lamination, the handle essentially being a core here.

[vinemaplebows]

Lyptus is a hybrid, you can read about it here.... http://en.wikipedia.org/wiki/Lyptus I have a fair amount of it, but have never tried it for a bow. I think it could be a good bow wood, BUT have read it is not. Give it a shot, and let us know!

Brian

[Prarie Bowyer]

The stuff I have is definately NOT a good bow wood.  To better articulate my question I guess I should ask if shearing forces are weaker or stronger in the riser section.