once upon a time...a hornbow...

[simk]

yeah, its been a while since I made one horn-wood-sinew-composite. but every time I make one I'm fascinated about what this combo can do.
this one is 57" ntn and pulls 60# @ 32". the horn and the sinew both are extremly elastic materials - they are about 10 times more elastic than glass. this results in very low stress for the materials  and that is why you can achieve pretty sick designs and bends even with fairly thick bending zones....
cheers

[simk]

...goal was a shorter bow 60#-32 which can be shot without thumb-ring.
thanx for watching

[Crooked Stic]

Its a looker----

[Pat B]

Very nice bow. Tiller looks great. 

[Kirkll]

Nice work!   Love those tips!

[Mad Max]

I like it

Kind of a selfbow/laminated bow with horn and sinew added

[willi]

very nice, your attention to detail is superb.

[Buemaker]

Good looking bow for sure. What did you use for core woods?

[superdav95]

Very nice indeed Simon!

[bownarra]

To improve performance - work on your sinew backing , the sals (bending limbs) are too long. Try concentrating the bend in a smaller area. Study the old hornbow designs to get the idea. This is tillered like a wooden bow ok but you are under straining the materials and thus losing efficiency.

[Buemaker]

I am thinking  that simk know most likely all this, but wanted to make a different kind of horn-sinew bow. Beautiful work, well done.

[simk]

Hey Folks - glad you like it 

Hey Bue -  the two core-woods I used are maple and french pear + there's a thin "backing" under the sinew from hickory. And you know, if you are a little weird like I am and make a little weird bows like I do, you  sometimes get these weird comments like I do. Nevermind. Mike probably just didn't find this model in his holy book 

[Mad Max]

1/16" Horn slat on the belly wakes up a Osage Selfbow

[simk]

1/16" Horn slat on the belly wakes up a Osage Selfbow

yeah, you can put horn on the belly of a selfbow but its not gonna make it any faster - but it is also not going to overpower the wood. I've seen people repairing a hinge on a selfbow glueing a little horn over it. for a hornbow you need at least 2mm of horn they say.

[simk]

well, I have two more orders for those weird bows - so I thought I'll show you some pics of the making....
...so first we make a lot of lams, then splice the horn with wood....then glueup the stuff...then nicely shape them....

[simk]

then we need to put on the sinew.
I here have two bows - one is planned 40# at 28" and one is planned 70+# at 32"
The small bow gets 60 gramms of sinew in total, the bigger one will get 75gramms - applied in two layers each.
sinewing is always a mess - and  even if you are well organized the whole procedure takes a little time. you start with preparing the sinew and split into even amounts. then the glue needs to be solved and warmed up which takes some time. it can only be processed well between 45-60 degrees celsius. If its hotter it will degrade, if its colder it will get sticky and finally gel - so always monitor your temp! also the bow should be warmed up, that is why I have a radiator above my workbench. once this is done you start with priming the wood with thinned glue. this should be done a few times until the wood gets shiny. then you apply the sinew. I do apply a whole course at once which saves a lots of time. once the sinew is on the bow it can be laid out more even before its gels. Once gelled and firm I do wrap the sinew firmy with elastic band. As soon as this is done I reheat the limbs with the heat gun bringing the glue into a liquid state again. At this point all excess glue is being forced out - and at the same time the sinew is formed into a nice even shape by the pressure of the elastic band. Let it cool again and unwrap. Now its time to dry - after around 10 days the equilibrium in moisture will be achieved, in other words: its dry and the bow can be worked further and you can string it.
this is what works for me.
cheers

[Mad Max]

Cool

[Buemaker]

Do you groove the horn and if so how deep are the grooves approx?

[simk]

No need for grooving bue! Mine come of the 40grit drum sander and I have reliable bond. I had hornbows failing but not in the gluelines. Grooving is for the pro's. I use my expensive 2k for the splice tough...
the whole thing really is no rocket scienece - in fact if you have minimal talent and skills its hard to screw up a hornbow