Asiatic Composite Build-Along

[tom sawyer]

All good suggestions.

I'm not too sure that scraping horn will have much of an effect, and I need to keep a certain thickness to protect the core.  Same for thinning sinew.  As far as reducing limb width, I could maybe do a little of that.  To get from 75-80lb, down to 65 (upper end of my comfort zone) I'd need to reduce width by 19%.  I think the limbs are 1.25" wide, so I'd need to bring them down to 1" wide.  I might get away with that without losing my lateral stability.  I may also taper it in from full width at the handle and siyahs, so it bends a little harder at midlimb.  That'll take some of the pressure off the ends of the horn that are butted up against wood spacers.

I also need to do a little work on my nocks ASAP.  I cut them straight in, but the string rides on the inner side and very close to the top at brace.  I'm going to cut them at more of an angle so the string sllides down in there better.  Probably line that area of the nock with some horn too, this walnut is light enough that it might get cut into or split.  I'll probably make another string with slightly longer loops, this one's loops rub on the sides of the siyahs.  I put duct tape on the area of the lops in contact with the nocks. I bet the bowyers-of-old would have done this if they'd had access to duct tape.  They used leather, which is just duct tape with no stickum.

As for finishing touches, I was thinking of covering it in silk and wrapping some areas with thread.  I have to deal with the tiller and weight problems first of course.  Possibly painting some Chinese symbols on it, something like "Yankee Go Home" or "Communism Rocks".  But nobody will know the difference.  Actually its more of a Magyar (Czech) bow though, maybe something that says "I'd Rather Be Drinking A Good Pislner".  Pilsen is a town in the Czech Republic, after all.

Then its on to the next one, I still have the other two quarters of the gemsbok horn for another attempt and they are the better pieces.  I figured I'd practice on the second rate material first.  This time, I'll know to make the core more like 3/16" and maybe tapered a bit.  Although, you see a lot of these bows and they bend hard early, so I don't know that a tapered core is the right thing to do.  Will have to research that one a bit more.

[tom sawyer]

More pics on the photobucket website, braced, full draw and just unbraced.

OK I finished watching the Korean hornbow video and learned a lot from the part where he tillered his bows.  Basically I had not tillered mine, so it was good that it had the poundage it did.  I bevelled the edges of the horn and thinned it a bit towards the middle, also brought down the width of the limbs just a bit.  I made the thinner towards the handle, since you ewant more bend near the handle on these bows.  I sanded the siyahs and cut the nocks in so there was more of a ledge for the string to ride in.

When I strung the bow I knew it had lost some poundage.  I was able to string it using the step-through method.  I measured the poundage and found it to be in the 60's, much more comfortable.  Also, the tiller was much closer to where I wanted it, the limbs were more even and bending reasonably well.  I still need to thin the midlimb on the upper limb a bit, it is bending a bit too hard at the handle in my opinion.  I took it out and shot a few arrows out of it.  This is a really nice bow to shoot.  When first unstrung it showed equal set in each limb, another indication that it is properly balanced.

Now for the bad news.  There is always bad news isn't there.  I inspected the bow and found that the limb that was bending hard near the handle, had a little of the sinew lifting right in the beginning of the handle.  Also, there was a small crack in the spacer wood on one edge, probably from the compression stress of getting mashed by the horn.  I heated both areas and got some 2-ton epoxy in both cracks, and it is curing now.

Why did this happen?  I think I was just being in too big of a hurry.  I should have wrapped those areas with sinew as soon as I saw that the bow had a good tiller and poundage.  Instead, I had to take it out and shoot it.  Ah well, I can't help myself.  Also, I will thin the horn a bit more at midlimb and take a little of the stress off that area.

In any case, I am getting close to finishing this sucker in what I feel is record time.  I have to wrap the fades with either sinew or thread and glue, I need to cover the bow with silk and do some decorative thread wraps.  I need to put a finish on the siyahs.  And then I'm going to call it a bow.

[Roger]

Awesome bow Lennie! You quickly came up the learning curve with this one. I bet your next one will be even better. Did you see any problems with the horn splicing you were worried about? Which video did you purchase for the  construction of the bow?
Great job bud!

Sparky

[tom sawyer]

I got Duvernay's Korean Bow video on DVD from Horsefeathersranch.  I only received it a few days ago, I'd already had this thing going just based on stuff I read on the ATARN site.  The Korean hornbow is a different sort of animal, long and skinny and VERY flexible over nearly the entire bow.  Lots of the techniques can be applied to other types of Asiatics and even backed longbows.  It was worth the money.

The parallel splices have held up really well.  One has a little more of a gap than the other but there's been no sign of anything coming loose.  Im happy with that part of the project.  Although, if I'd been more careful when I was flattening the gemsbok horn,  I might not have had to split them in quarters in the first place.  I'd have had enough horn to run over the handle in that case.  That would have been better than the cut and paste approach I took, with the wooden handle piece on the belly side.  But this way, I have enough horn for two of these bows.  Its a cheap way to go, I got the gemsbok horn for $30.

I'm hopeful that with the glue, and a good solid wrap job, I'll have a shooter right out of the gate.

[PatM]

Lennie, There are plenty of examples of composite bows made with multiple strips of horn.
      I'm curious as to why you didn't reflex the bow more. According to Tim, the bow should only shoot as well as say a sinewed osage of the same profile. Unless of course you draw it much further than you normally draw to maximize the sinew /horn potential.
    The drying time seemed a bit short. Have you beeen hanging out with Thimo lately ?     Pat

[George Tsoukalas]

Lookin' good, TS. Glad you've made such phenomenal progress before the Series started-you lucky dog. I'm glad for you. Jawge

[tom sawyer]

Jawge, I just work on the bow until the game comes on.  Its a matter of time budgeting.

Pat there are composite designs that don't have that much reflex.  Honestly though, this design is more from my head than from any particular artifact.  I was thinking I'd get more reflex out of the sinew, the horn on the belly must have made it too stiff.  In any case, the bow has a good 4" of reflex and that is probably enough for my maiden voyage.  I've heard of horn being spliced, mostly I think it is butt-splicing to get more length and not parallel splicing like I did.  Most horn is wide enough, but not always as long as we'd like.  As for performance, it'll be what it is and I'm not worried about setting any records.  Just having it hold together is my goal.  It should do alright because the horn is thin now and the sinew layer isn't terribly thick either.  I chose a bamboo core and the walnut siyahs because these materials are lightweight.  Drying time on the sinew was adequate but I'm sure it'll continue to gain weight for a few months, might even show some more reflex now that the horn is thinned and the limbs are not so stiff.  In all, my guess is that this bow will slightly outperform a same-length sinewed osage bow with similar reflex, just becuase the limb mass is going to be slightly less.  And I'll look cool!

Update:

Today I wrapped both the handle/fades and the inner siyah areas where the horn terminates, with sinew.  There's a pic on the link above.  Now for more waiting.  When its dry, I'll cover the back with silk and put some finish on the siyahs.

Mims questioned my choice to cut out my siyahs rather than bending them.  IU've thought this over a bit, and examined the bow.  I kind of like how the grain is running on the walnut.  I cut the siyahs out of a board rather than bending wood.  This has the grain running parallel where the siyah is spliced to the core, and at an angle of maybe 30 degrees in the direction of the outer siyah.  This offest means that the string is not pushing straight into the grain at the nock.  I've had nocks split in the past, and I think the angle of the grain will help to prevent this.  The fact that walnut is also only semi-ring-porous is good too, theres no spring ring to be the weak link that splits when the string is pushing/cutting into the nock.  I'll put a bit of leather in the nock just in case, but I don't know that it needs it.

[PatM]

Lennie, I believe most Indo-persian bows were made with  about five strips of horn on the belly of the limbs. You can look at the Khotan bow on ATARN as another example of a multi-strip bow.    Pat

[tom sawyer]

I'll definitely check it out.  I wouldn't necessarily want to have more joints to try and get mated, than necessary.  But its nice to be abel to use these skinny strips after paying $30 for the horn.

[DCM]

Looks fantastic Lennie.  Hope the little damaged area doesn't spoil it.  Still, for a first project I'd say it turned out great.

[tom sawyer]

I'm hoping for the best, got 2-ton epoxy in there pretty good and a nice thick sinew wrap.  I'll weaken the midlimb area a bit and hopefully that'll take some of the pressure off the fade area.

I got a tip from Adam Karpowicz, to reduce mass in my siyahs.  If I cut the nocks an inch closer, I'd lose the better part of an inch of reflex.  But I'd gain from having less mass and a little more poundage to play with in tillering.  I'm not that close to being at a 90 degree styring angle at my draw, although if I were to draw to my ear I might just about get there.  Anyway, I'm considering this option while the sinew wrap dries.  The walnut siyahs aren't that heavy but they are somewhat exaggerated compared to most authentic bow designs (I think).

In fact, does anybody know if this bow looks like any of the standard ethnic designs?  So I can call it that?  The siyahs are too long for Turkish, nothing like a Korean, maybe a Chinese?  The Chinese bows have long siyahs but at more of an angle, with pads for the string to lie on the bow at the knee of the siyah.  I think this bow is most like a Magyar (Hungarian) in terms of siyah length and angle of braced bow.  Might lack a bit of reflex but otherwise it seems to be the best fit.  This is how I brew beer too, throw stuff together and then classify it after I taste it.

[PatM]

Lennie, Mini Magyar is the  classification for this one.    Pat

[tom sawyer]

True, I'm an inch or two short in siyahs, working limb and handle area.  And I don't have the reflex of the genuine bows, more like the profile of the reconstructions of Fabian Gyula (sp?).  Probably for the best, if I had much more reflex I'd likely be having more trouble with twisting of the limbs, as one of my siyahs isn't lined up quite as well as it should be.  I'll pay more attention to that on my next one.

Mini-Mag seems like a good name, if the bow survives the next week or so.

The sinew wraps are drying out quickly, the RH is low right now.  I've been fondling the bow nightly, can't wait to fine-tune the tiller and finish it up.

[venisonburger]

I've been watching from the start and this has been a fascinating project, I always wondered how these bows were constructed. thats quite an accomplishment you've made.
Can't wait to see the finished product.
VB

[tom sawyer]

I couldn't stand it, I had to string the bow this morning.  The tiller looked very even (1/8" positive), the poundage is at 60lb@27", I shot it a few times and it is performing well.

I have to do some prettying of the bow now.  A little sanding and polishing on the horn, gluing some silk on the back, sanding the siyahs and finishing them.  Some sort of handle wrap.  Then it'll be done.