Kviljos crab bows

Hey , friend- congratulation- first bow looks like Turkish :D Very short part between V splices in sal - to me.

Hehe :P

I was looking through Adams book yesterday after I published the pictures, and made the same conclusion... But I don't think I will convert it into a turkish war bow, since they did not have the extra spliced in kasan pieces. (?) I will try to make the kasan angle closer to 90 degrees and straighten the tips slightly. That ought to make it more like a crab bow. ...I hope :)

The non-spliced center part of the sals are quite short. It is made according to Retos drawings though. Perhaps the grip splices are a bit too stretched. I don't think it will matter anyway. The core won't be thick at all in this one, as I'm hoping for a draw weight of at least under 70 pounds.

Anyway - good looking bow now. Good luck .

Look at the Russian collection- Andrew Hall post Ingo Simon collection vith bigest nombers "Crab" bows what ever i see !

Thanks for the tip! Huge collection of goodies there!

I adjusted the angles a little tonight before I started glueing the parts together. When I clean up the core after glueing, I think it won't be too far from the original.

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Yes :wink: .Better angels . Good work.

These grooves may or may not be historically correct on this type of bow. As I am not an expert when it comes to glueing with hide glue, I think I might need the extra surface of the grooves to make sure the horns won't pop off when the bow is ready for tillering.

I found that my 1,5" broad grooved scraper was neither as effective or giving as good result as this four-thoothed scraper. The main advantage is that it is easier to file four teeth even, than filing 24 teeth :) - plus it is much quicker to sharpen and much more effective to work with.



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The core and horns are now drying from the first five coatings of very thin hide glue.

What is width and depth of the teeth?

I assume you made that tool yourself (and if not please tell where are they sold).

They are about 2mm deep.

A scraper and a small triangular file will give you as many of these as you will ever need :)

I think that the matching grooving affect in two ways.
1. It adds glue surface area
2. More importantly the material change is no longer instant, but happens
over distance.

I do not know about natural glues, but the general delamination with
epoxy happens not at the glue line, but in the material next to it.

I would assume that the matching grooves decease the likehood of such
thing happening.

That might be it, but according to Adam, the matching grooves have not been used in the handheld composites before 1900. It is used in the european horn crossbows, though. But the constuction of those are quite different to the asiatic composites.

- so I'm not trying to match the grooves exactly, although they will match partly anyway.

I glued the horns to the core today, by the way. This was the fourth time, and the first time I wasn't completely overstressed by the process. With a lot of preparation and re-hearsing, it went very well. Pictures to come.

Looking forward to shaping the bow and starting to lay the sinew!

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I know that they may not have been used historically.

I am primarily intrested in 'things that can be done'...

BTW:
Isn't bow with so much iron so heavy and prone to fall on the side?
I think these are much easier to use: (providing the 50mm is enough)
http://www.clasohlson.fi/Product/Produc ... =134587814

with 2.90? they are dirt cheap too.

Yep, it is a bit unsteady, but the core is quite sturdy so it didn't bend. I hope it is still standing in my workshop, though. :oops:

I've been looking for some small C-clamps, but haven't been able to find any locally.

Progress :D

Sorry for the large picture...



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A great looking bow Kviljo, hopefully I might have a look at it some day! :D Keep on gathering experience, so others in Norway can cheat on your expertise. :twisted: I now have horns (from you) and Adams book arrived yesterday, the fun can start! :shock:

Yep, from now on, every tiny bit of spare time has to be used for processing sinew. :wink:

I'm currently preparing a bunch for this one. It is taking too much time. Hopefully it will be ready for the competition in the end of august.

Dude that looks slick...very nice. I love seeing a build-along that actually has all the pieces laid out so people can see what's going on. It took me months of searching to find a picture of an unassembled bow without having to buy a whole book for it.

I can't ever get splices down, though. I'm currently building similar bow from oak and brazilian cherry. Using a few non-traditional materials to hold it all together for my first attempt. But I keep getting snagged on the splices! I apparently can't cut a splice to save my life! Nothing lines up...whole stave is ruined...so disappointing. All comes with practice I suppose...

Thanks :)

I used my bandsaw to make the splice cuts, and adjusted the male part on the belt sander to make them fit and line up good. It usually works out quite well if I don't rush it.

I've botched it with a band saw...I can get the sides to match flush but it seems that the process to get them there leaves my center line off. Or I get the center line straight, but my surfaces aren't mated smoothly. And sometimes, like the bow I just started, my line is crooked, and my center line is about 1" off, and twisted, at the limb ends. After the sayahs are on it's going to be way off. I'll have to do a lot of steaming with this bow.

I can say, though, that I modeled this bow after yours in a fashion....I usually tried 4" splices but yours seem longer...especially in the handle. I made my handle splices 8" long and it was a lot easier to get them to line up, and the handle looks so much better...nowhere near as nice as yours, but better than I have done before.

I look forward to seeing more pictures of your work!

Yes Kviljo, very clean, studied start.

Thanks guys. I'm slightly worried about the birch core and birch siyahs, but I'll wrap this one thoroughly.

I've put 20 grams of sinew onto it now. Hope to spend 80g more on it, everything included. It is following the measurements that Bede posted with the cross sections, except I hope it will be about 1mm thinner.

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:shock: top !

I found the time to lay the second layer of sinew tonight. It has gotten 57 grams of sinew now. Hoping to add one more layer, plus the final wrapping.


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Oh Crap!

During last week the horn delaminated from the core... I pulled it into too much reflex while the glue-lines in the handle got too moist from the sinewing... Not sure if I will be able to save it. I will probably soak it and re-use the horn and sinew, but untill I have a new core (this time of maple) it will have to hang shamefully on the wall together with the other expensive lesson... :roll:

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Kviljo, a I guess thats a glue- failure. I don?t think that adding the sinew could cause a dissolving of the backing. Maybe the backing was not hardened enough.
You know I?ve rediscovered selfbows and enjoy the making of them more than ever and much more worth than every other type of bow. So what?s the design of the 10th bow from the top in the background(last pic). Very interesting bows!
Michael

redhawk i think thats a Holmgard.

It's an extreme ash mollegabet/holmeg?rd - 3" wide by the fade and 5mm at the tip. Even the thick tips are bending slightly. 70# @ 28". Not too fast, but a fun experiment :)

The horn/core glue line had been drying since April, I believe, but the glue felt soft to the touch now, so it must have gotten rehydrated and failed because of the reflex I pulled into it. The crosswise shrinkage of the sinew have also done a little damage, so the glueing surface of the core is not plane anymore. If it was plane, I would probably try to reglue the horn. :x

Kviljo,
very impressive work. I do not know why i am impressed about tips, look very fine at the pic. Can you tell me dimension of tips pls?

Thanks, I think they look quite like some I have seen photos of, but they might not be exact. Have a look at what I had a look at when I was whitling them:

http://198.170.107.188/phpBB2/viewtopic.php?t=1469

Perhaps some of you have had the same happen? Is there any limit to how much sinew one should put on the bow at once, considering the danger of rehydrating the core glue-up? - or may there be another good explanation?

I does not look like too much reflex after sinew or sinew shrinkage could cause this delamination. It may be as you say the excess of moisture (humidity plus the wet sinew) plus a weak, perhaps too porous glue line betw. the horn and sinew where the water had access. I have not seen it happen before.

I would try to save the bow by dipping the limbs in glue to flood the joint and binding the horn to the core again.

Adam

I have had delaminations but never so extense.
It has always been a glue-failure. Glue to thick, temperature to low...........
warmth is the key for succesfully working with natural glues.
I would follow Adam?s advice and not give up the bow.

Michael

Hmm, I might have used too much clamping pressure when I was glueing the horns. Although the bond seems alright from midlimb and outwards.

Not sure if I will manage to save it, because the V-splices in the handle has failed too, making the core glue surface transversely convex. I would have to soften the sinew considerably first to be able to force it flat again. Or perhaps I could just force it together and hope that the horn will follow the curvature... Hmm. I'll probably just make a new one.

Just soak it untill it's in pieces, and sell it as a makeyourownhornbow kit :wink:

Kviljo; In my experience it takes three days immersion in water to loosen the bond between horn and wood or wood to wood. Are you thinking that there was too much sinew applied at one time holding in moisture? Will you change your sinewing technique?

Do others pack on sinew at one time? Or make several applications allowing drying in between applications?

Ai, three days... It might have been a porous glue line that collected some water during the sinewing, as Adam suggested. - Because the glue in the failed glue line showed signs of having been moist when it let go.

It went well during the first layer of sinew, which got two weeks drying time before the second layer. It failed when the rather thick second layer of sinew was drying.

Not sure if I will change anything, other than trying to make the horn/core bond better. Are some of you putting on all the sinew in one go? I thought tree layers was nice to have to be able to reflex the bow inbetween the layers.

For to be honest, I?ve never trusted in backing sinew like it is historically delivered and proven. I always applicate the complete backing, very carefully avoiding too much glue and squeezing out the water of the sinew.
I leave the backed bow for 1h, than I wrap it heavily with strips of a highly absorbent quality of linen(usually an old dishtowel).
Every now and then, when I?ve miscalculated the necessary amount of sinew, I add a layer or some bundles of sinew. Again I take very care of avoiding too much glue and water.
That?s it.
As I?ve mentioned earlier in this thread, any arising problems are nothing else but glue- failures.
Michael

Thanks for your honest...

I am a greenhorn..I also used only two layers: put sinew in water, comb, squeeze, put in thick hot glue, then on the bow - this starts to gel immediately and cannot wetten anything, completely dry after 12 hours .. at least this was suitable for a strong bow which did not fail on brace.
:-)

It looks like I might be able to start on a new Crab bow some time soon now. I found some nice inspiration at the Saluki-bows gallery. His work is simply stunning!


I have only seen crab bows being explained as having a wood core of seven parts: grip, lims, "kasans" and siyahs. I am not sure how this bow from Saluki was constructed, but my imagination tells me that it could be made as a five-piece construction. - with the siyah and kasan ridge as one piece, with the thinner core bent up on the sides of the kasan ridge to form the wide kasans.

With this kind of construction one would not be dependent on finding a naturally bent piece of wood for the "kasan eye"-bend.

Are there any clues on original bows that could tell us wether or not they always were made with a seven-piece core, or with five pieces the way I tried to explain?


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If you are very interesting , you can personaly talk vith Luk?? Novotn? and see , and more- shoot vith his hornbows. Luk?? come in Czechia near Prague in next 2011 "Nadaam" meeting(may/?/) vith all his last bows. If all be good vith mi last gen. composites , i be there too :lol:
I know - long distance- but closly than South Amerika :lol:

I have only seen one original crab bow dissected and it was not clear that the tip was spliced into the kasan. However it is very clear that the kasan was bent and spliced into the straight part of the bending limb.

Your suggestion for building the splice on the kasan and having the main bend in the dustar is interesting. I think someone should try it. It was an idea I had too, but I discarded it after seeing the cross section. That does not mean it was not used, just that I haven't seen any.

Jaap told me that Lukas had seen the dissected bow. That only indicates that he knew about it. He is an artist and, if something is difficult, he will do it if it achieves what he wants. It is probably best to ask him directly. he may have tried many different techniques. Edward McEwen told me that he had only seen bows spliced at the bending section in the many crab bows he dad examined.

The tip splices were common, but if you had two pieces of wood with he right grain it would be natural to use them without a splice. Since the tips were small, strength was probably an issue.

Hi Iam new to this forum, and have been reading (absorbing) all the new information like a spunge.
After purchasing Adam his book in spring I started building some hornbows.
I also started a crabbow, and did it with 5 pieces, because I thought it was costructed this way. The siyah splice runs all thw way till the kasaneye. I hope it will work. In my bow the hrorn is bended around the kasan eye and runs almost till the tip. So it only has to run untill the kasan eye in the original bows?
The wood I used is fraxinus excelsior for the sal, juniper for the siyah and yew for the grip, horn strips 45 cm long. I used the saluki crabbow as an example. One of the kasans bends abit less steep
Think I put about 80/90 grams of sinew on it.
Is it neccesary to put sinew on the belly as well?

Alex
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Kviljo wrote:

but my imagination tells me that it could be made as a five-piece construction. - with the siyah and kasan ridge as one piece, with the thinner core bent up on the sides of the kasan ridge to form the wide kasans.

Originally I thought that they might be made this way - a joint kasan/siyah piece carved out, with the limb simply bent around it (I thought the same thing about all bows with the ridged kasan, actually).

When I started coming here, I realised this was false, but never found out or thought up why. It does seem like a much simpler way of making it.

I had no idea on how to make a crabbow. Thought it was like a turkish bow, that s why I took this approach of 5 pieces.

I had some trouble bending the siyahs however, took too short pieces, and was left with to little leverage to get the right bend at the kasan/tip.
Therefore I laminated some wood on the tips to get some more reflex in the tips.

I found it much harder to get reflex in the bow, while putting sinew on. Felt as if there was more resistance. Therefore I decided not to make a full circle.

I hope its going to work in a couple of months, but if i read the other post about making a crabbow (i think the post was JJ) than its going to be not that easy....

alex

Alex I did it this way (making sal very long with the siyah bend in it). It worked but I had some problems aligning the splice; the fact that the splice is very long and extremely curved makes it difficult to handle while glueing.

After it?s done and aligned well it is very stable.

JJ

Since my original comments about the horn on crab bows, a friend found me a copy of Balfour's paper on composite bows.
Author: Henry Balfour
Source: The Journal of the Anthropological Institute of Great Britain and Ireland, Vol. 19(1890), pp. 220-250
On the STRUCTURE and AFFINITIES of the COMPOSITE Bow.
By HENRY BALFOUR, M.A., F.Z.S.

This contains a detailed discussion of a broken crab bow with some careful line drawings of the cross sections. This bow also had a narrow horn strip under the sinew on the belly.

The wood core... is deeply and
neatly grooved longitudinally towards the belly, in order to
give firm hold to the glue, which forms a fairly thick layer (h)
between the wood and the horn. The horn (b) is composed of
a single piece in each arm, and not composed of strips as in the
Persian bow; its surface is grooved towards the wood. The
horn does not extend to the edges, but is overlaid with a
stratum of longitudinally disposed sinews, similar to those on
the back, and apparently a continuation of them. The sinews
are in a double layer; one layer, n1, composed of sinews with
little glue mixed with them, does not extend over the horn, but
fills up the space between it and the edges; this is a continuation
of the inner layer of the back, c1. The outer layer, n2, overlies
both horn and inner sinew layer, n1. The shape of the belly is
thus to a great extent given by a padding out of sinews. The
outer sinew layer, n2, is mixed with glue or cement, and has a
dull grey brown colour; this is coated with a kind of red brown
cement, the surface of which is smoothed. Over this brown
cement lies the peculiar thin metallic film, which is extremely
delicate, and it is difficult to prevent its rubbing off when
exposed. To this is applied the external ornamental lacquer
coat. It is not easy to account for the substitution of the
metallic layer for the bark one, as it seems to be but an indifferent
vehicle for the lacquer, which flakes away from it
rather easily. The external sinew layer of the back, c2, differs
from that on the belly in being only slightly mixed with glue
and having none of the grey brown cement.

The letters in the text refer to the diagrams in the article. Balfour was not aware of the type of glue and speculates in another part of the article. The article also contains the dissection of a Persian bow, the diagram of which appears in Turkish Archery and the Composite Bow by Klopsteg.

Bede that sounds interesting with the different coloured sinew/glue layers. Is there a way to post descriptions and pictures of the construction of the crab bow from the article??

Best regards, JJ

JJ,
I think it might be in breach of copyright in some jurisdictions. I was going to redraw it for an article I am writing so I could schedule that ahead of time and post some preliminary drawings here.

If you be a user of www.jstor.org you can download this article and other article about archery.

Sounds like an interesting article!


A small update on my bow: I grabbed the separated horns and tried to pull them off a few days ago. I was surpriced to find out they nearly did not stick to the core at all, even at the places near the "kasan eye", where they looked alright. There must have been a glue-issue, which have become more clear to me through the last days. I got a thermometer and checked the glue-pot temperature, which seems could have been as high as 70-75 degrees. Also, parts of the glue I used had probably been heated and re-heated a couple of times before it was used too. I'll be using fresh glue from now on.

In the glue mixture I also used perhaps 15-30% of some handy liquid fish glue that I got hold of (the 80-85% rest was hide glue). The fish glue is more brittle than the hide glue, but I liked that it lowered the gelling temperature. It does smell of preservatives, though, as a part of it has not gone bad even though it is a year old... I think I will give it one more try. Anyone here have had experiences with "regular" fish skin glue - not bladder glue?

I'll be making a new crab-core one of these days, and reuse the horns.

i've never used fish glue but i have added home made sinew glue to store bought hide glue, with the result that setting took longer. The end result: good hold.

I made this form a few weeks ago, and when I saw Dusans photos of his highly curved cores, I got the courage to try and bend some wood on it.

It is green maple soaked for one day, boiled for one hour. At the bend it is 12mm thick. Not even a lifting splinter 8) Working with undried maple is like heaven. I can't believe I was staying with kiln dried boards for these jobs. The difference is really huge.

Perhaps this picture illustrates what Adam termed "scooping out" at the tip/kasan bend for the turkish cores? It seems important to whittle an even surface in the scooped area to avoid collapsing the wood on the inside.

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I haven't decided yet wether to just splice in a tip, or splice in a tip that has the "kasan" ridge in it. A long splice is perhaps more difficult, but it will take a lot of sinew to build up the ridge otherwise...

:lol: yes. Fresh wood is miracle :lol: One of old known steps for old wood craftsmans , but novadays ... /but its only in ours "hi civilisation" 3world know about it/

Holy cow, thats some example...

So, finally I found the time to start on a new crab. The bent core laths in the picture above was used for this bow.

I re-used some sinew that I had put on an angular bow. It took about 7 hours submersion in luke warm water for the complete layer to dissolve enough to pull it off and separate into new bundles. This was the first time I re-used so much sinew, so I was quite happy that it worked alright. The grooving from the core can be seen in the picture.

As you see in the pictures, I used a fairly narrow strip of horn on this crab, as suggested by Bede among others. The rest of the width, plus the surface of the horn will be covered in longitudinal laid sinew. I will need to build up the ridge on the outer parts of the limbs with sinew, something that is also said to be an authentic way of doing it here on Atarn. The bow will follow the original measurements from the bow that I posted in the "Hardware" section.

The core with horn is 9,5-10 mm thick in the bending section - I hope that is reasonably close to the original. I bet it will be a very heavy bow, but maybe it will be manageble with the rather small amount of horn.

Any comments or suggestions are very welcome :)

Here's the core, btw.

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Weee! My second try for the crab bow seems to be going alright. I've put on it about 50 grammes of sinew now, including a thin layer on the belly, but I suspect it will gain another 50 grammes before I dare bracing it. It is weighing exactly 500 grammes now, so it will be a fairly heavy bow when it is finished. But, I suspect it will be quite heavy in draw too.

Anyway, tonight I cut the tips in half and inserted the horn. Not quite sure how deep the cut should be. These are about 6cm long.

great. keep posting :D

Will do :wink:

Here's a comparison, hehe. I should maybe have pulled it into more reflex, but I hesitated a little because of the rather high pressure that was needed to pull it into this shape. Maybe I will heat it a little and pull it into more reflex next weekend. Anyway, it will have to dry quickly, because I will start bracing it in the beginning of august 8)


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Hehe, I just could not hold myself anymore and had to start bending this bastard :lol:
My goal with this bow is to have a shootable and hopefully durable "crab" bow, so I am not so concerned about how much string follow it will gain. Over time it will probably land at about the same string follow in any case.

Soo...I put some tepeliks on it tonight, after some three-four weeks of drying. It now weighs 517 grammes, and seemed to have stabilized there.

It's got fairly large limbs, so I was quite surprised to find that it was very flexible. Parts of that is surely because of the rather short curing time, hehe, but the small amount of horn is probably also contributing to this. No doubt it will be of fairly high draw weight in any case though.

Before I was putting the tepeliks on it, the tips were about 10cm apart. After four hours tied to the tepeliks it opened up quite considerably, which I am fairly happy with. It seems to bend in the right places too, so unless some bad adhesion between the sinew layers will cause trouble, I think it will be a shooting bow in a few weeks.

I am however not sure what I think about the sinew on the belly, because it crazed a little in the bending parts, which I suspect will give me some trouble when putting a finish on it. Any advice? I was thinking of simply putting on shellac with some red pigment in it (and maybe paint some flowers on it, like the original).


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Hi crazy Norwegian bowyer :) !
You know it is really interesting to watch all of your postings! Thanx for sharing !
Your second crab bow looks gracefully! You have a good feel of forms!
But why are you so hurrying ? I think it will be much better to keep the bow seasoning till autumn.

it seem your glue is weak, or too weak, how long time this glue will works good on the bow if same glue on core and horn?

i hope you can from Norway sea or river got some bladders,or rabbit hide,you are less glue test step when you decide use it for make a bow

Hmm.. I am only beginner for now, & my first hornbows will appear not earlier than in autumn, but I have had such cracks of hide glue on my sinewbacked reflex bow after pulling it too much on tillering stick(it was 2 layers) So I decided to coat the back several times with the hot glue& put the 3rd layer for safeness. And it helped :) The bow still alive after 100shots

Thanks guys!

I would not take the credit for this bows curves, because I have simply copied an original bow :) But I am very happy with it's shape so far.

It would certainly be better to wait at least a few months, but it was too hard to keep the fingers off of it ;) The second reason for starting now is that I really want to give the bow some string follow, so that it will be easier to handle and so that I can be sure that it will be a shootable bow. And, I hope to be able to shoot this bow at the annual competition in the end of August. I have another similar core ready for horn and sinew that I will give longer curing time. Also, I have seen others here string bows in "no-time" after sinewing, and I wanted to give it a try too. As long as the bow is fully dried I feel like there is not too much to gain with waiting for it to cure more. - but I am sure I will laugh of this later, when I have experienced the real difference in a "fresh" bow and a properly cured bow.

Jiao; Why would you suspect the glue is not strong enough? I have used a mix of fish bladder glue and hide glue for all of the bow.

Anyway, the sinew on the back seems to be fine and as it should be. The close-up picture is from the belly, showing the thin sinew layer that is put over the horn. Maybe I could simply sand it after having braced and shot the bow a few times, and then put a finish on? Glue and sinew surely does not have the same compressional capacity as horn, so I guess this is something that is difficult to deal with. - or maybe the sinew on the belly was not laid lengthwise on the original bows? Or perhaps a thicker layer would not craze like this?

iao; Why would you suspect the glue is not strong enough? I have used a mix of fish bladder glue and hide glue for all of the bow.

the transverse break line on sinew , it is not the sinew break,i have test the hide glue, the un-fine sinew string and too dense glue, it will be yellow and white color on sinew layer, the white sinew strings not suck the glue, i use hide glue and bladder glue add too cotton cloth, the hide glue very weak,the bladder glue let cotton cloth "stand" and "shoot" well . the korean bowyer test the glue on mustache, i think we can got longer hair form woman of home. so. plese do a test show the result us of your hide glue ,fish glue , hide mix fish glue, the glue dry on your hair or cotton cloth(or cotton thread), bend it as the bow bend degree or curve, i think it is good test of glue for sinewiback

:D great job !

Great :) I was hoping you start oer bending the bow before August :)!
The bow looks also great to me, except for the feeling there might be a bit more bending left hand side next to the grip, but this may be because of the picture.
According to the sinew cracks, I think that it is normal. I experienced a bit (!) the same while trying to heal a bow in the Sal/kasan bend with a sinew wrapping: lengthwise laid sinnew can stand tension forces very good, as you all know. On the contrairy it cannot stand compression to the same extend especially when laid thicker. It cracks. And the other way around for crosswise laid sinew. this can stand pressure very good without cracking but breaks on tension very easily. Especially when laid thicker.
I was thinking of, how one can use sinew/glue to "immitate" a bit of horn (in case this was a limiting factor in supply) on the belly without having the cracked horn on the back (like I had with the wrapping). I ended with a compromise : Diagonal laid sinew, like many of the old bowyers practised! It may not be as good in compression on the belly as crosswise laid sinnew but it may not crack in tension on the back also :). However I never treid diagonally laid sinew so it is just a mind experiment :S.

Best regards Kevin

I agree with Kevin. The sinew will start to turn white if there is a problem but then watch out. Actually an overall whiteness to the sinew is normal.

I?ve to agree with Jiao about the white lines within the sinew, no sinew- cracks but glue-cracks, so the glue seems to be to weak.
Usually I become very nervous when those cracks are appearing within a sinew- backing, done everything allright with the glue, there will be no cracks.
Hope this great job will work out fine!
Michael

Hi Kviljo, great job.I would like to build a crab bow someday. I think you should move the tepeliks more toward the end of "sal":it will give a higher string-"kasan" angle, increasing stability.Very well made bow,anyway.

Francesco

Ah, now I get it Jiao! I think you are on to something there. Maybe it would be better to use pure fish bladder glue for the belly sinew. - or in fact better to use bladder glue for the whole bow. I usually add as much hide glue as possible to the mix because the hide glue is cheaper than my home-made bladder glue. But maybe the original bow was not as cracked on the belly because of use of more elastic glue. I will definitely try this for the next one. - or maybe I should try some rabbit-skin-glue for the belly sinew.

This cracking confused me, because it seemed like the experts here on Atarn agreed on that these bows had lengthwise laid sinew on the belly, and were not wrapped. - with the only exception of some diagonally laid sinew at the "kasan eye" bend.

I will try to get the outer parts of the limbs to bend a little more, but I am a little wary of making them bend too much. The original showed no signs of heavy bend there - only in a rather short area 1/3 out from the handle. That's where the varnish was cracked anyway, and its dimensions also indicate that the outer parts of the "sals" will not bend much. Also, I made the knee-angle in a somewhat unconventional way with no splice and the full ridge built up with sinew, so I will be somewhat careful with that area untill I see how much it can take.

Thanks again, everyone :) I sure too hope that it will survive, at least for a few shots. I'm quite excited to see the full-draw profile of it, hehe. The bow is now resting with a stick between the tips, to open it up some more.

I had such glue cracks when I used too much (or too concentrated) glue. Probably a minor effect on efficiency but otherwise no problem.

Regards,
Daniel

Congrats, I like snew job. Did you wrapped the horn side?

Cem

Daniel, yes, it's probably nothing to worry about, even though I think it might prevent me from giving it a smooth finish on the belly side in the bending sections.

Cem, yes, the belly is also fully covered in sinew, but laid lenghtwise. The picture is of the belly side of the "sal". I think it is possible to see a little of the horn through the sinew, although it is not as broad as the limb itself. I should probably file the sinew smoother before I finish the bow though.

Kviljo,
Why you did not wrapped snew transversal?

Cem

I read some post about these bows here on Atarn. If my memory is correct it was Bede and Adam who were discussing how the sinew was laid on the belly. They mentioned at least one bow which it was possible to see lengthwise laid sinew. A sinew wrapping would certainly have been somewhat more calming, but the limbs have very little glued in reflex, so I think it will be alright. - if the 90-degree bends will be okay.

I think even with sinew laid lengthwise there would be some transverse contraction when it dried.

recently i buy 4$ bladder and leg sinew, the bladders glue boil at 50c for 48 hours,never it can gel, i use it glue a few sinew to 1cm wide 10cm long bamboo and separate bamboo and sinew layer(very very a few glue can not glue the bamboo and sinew), one day it dry, it has crack, i can use fingers rip the sinew string for sinew+glue, it is failing result, but it has no problem bend more like c and elasticity very well,

other test is i am not use glue for sinew, two bamboo slice compress sinew, one day for dry, it has no crack, and i imitate raw leg sinew structure not straight all fibers, it is fast the all fiber straight, i can use fingers rip the sinew a few string form edge, no problem bend more like c and elasticity very well, but slowly comeback to straight shape

i well post some pictures

That's very interesting Jiao :) Then it seems I will have to use more pure bladder glue for the belly sinew next time.

Pictures would be great!

http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765583690
form left to right
1, bldders glue and sinew(failed)
2, pure sinew compress(failed)
3, a test of i try copy juyuanhao pure white sinew technique(failed)

but 1 and 2 no problem for any bend test,2 is good "shoot"

1 and 2 size 1cm 10cm, 1 thickness 1-1.5mm, 2 thickness edge 2mm middle 1mm(some edge sinew out of the bamboo slice so it not compress)

the pics of 1
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765644324
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765604410
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765634309
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765573944

the pics of 2
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765634419
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765604450
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765644331
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765644379
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765614413
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765634379
http://photo.163.com/jiaoy7/#m=2&aid=24 ... 7765583752

all pics here
http://photo.163.com/jiaoy7/#m=1&aid=241654324&p=1

Cool, Jiao! I will try this for my next one. The cracking of the sinew on the belly seems to only get worse on this one... I'm sure it won't do any major harm to the bow, but it will make it hard to put a nice finish on the bow.

Anyway, with some help from my wife, I managed to put a string on this bastard today. It will have a huuuge brace height! What a beast to string...!

This is what it looks like now, before any heat-correction. I was surpriced that it bent this much in the outer parts of the limbs. I still have to shorten the string a little to let it lift off of the "kasans".

Anyway, any advice/comments are as always welcome :)

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Wow!!! We wait it!!
REAL CRAB!
My congrats you put the string!! yes a brace hight a bit too much & need corrections but anyway your bow looks very cool!! Keep going Kviljo!!

:shock: great. you made it !

You might make some special tepeliks to concentrate the bend near the ear/bending limb transition. Most old paintings show the bows bending more farther from the grip. Remember the illustrations from Mustafa Kani: the bows when first braced were bent close to the grip and looked like this.

Hmm, very interesting, Bede. I am worrying a little about the sharp bends close to the grip. I guess it will only get worse when it is drawn. But then again, it is following the dimentions of the original bow... I will try it!

It is a good advice to ease the stress at the grip by heat bending closer to kasans. I believe this was done with most hornbow styles. My old crab bow has signs of bending mostly about mid sal during use, but it could be that it was overbent at the kasans with heat beforehand.

In this style of bow, the energy storage depends on good reflex. It is because the tips are almost straight after kasans, which makes the bow almost a non-contact recurve. Then, with no "lift-off", the bow behaves as a very short bow with the usual horrible stacking. Combine that with the heavy kasans and the efficiency had to be very low. If not for the reflex adding the hump in the f-d curve, the bow would be mostly for show. I believe these bows had to be used when really dry to keep the sinew resilient enough to retain the reflex as much as possible.

I strung and drawn my replica, but lost interest in this style once the stacking became evident. Please let us know what you find.

Adam

Hmm, in other words, heat the bending part and give it more stringfollow in the areas that should have been bending more? That would definitely ease the process of making it shootable, since I have already put on the sinew on the belly. I didn't think of that as a good solution, but maybe I should try it if I don't manage to persuade them to bend properly with just pressure.

But could this really have been done with the old bows? The original bows that are curled up with tips almost touching, that also show signs of having been used, tells me that there is something in the manufacture-process that is different from the way I did it. Surely, I did not let the bow cure at all, but it is now almost straight with the "kasans" pointing forward. After some use, I am sure it will have only a few inches of reflex left. Could 100+ years of resting really make the sinew draw the bow back into it's curled up pre-bent state even if the "sals" in some places were given extra string follow with heat? Or maybe the core of these bows were made like the Korean bows, with tips touching before applying sinew?

If I remember correctly, I think Bede wrote here somewhere that Edward McEven made some crab bows, and apparently reported on really high efficiency. I agree with your thoughts about the design - it seems akward, but maybe we have done something wrong? With such a technically dependent tool as bows are, it seems unlikely that they were sacrificing too much punch in favor of style. - or maybe there is some other and better explanation for this weird design.

I will keep you updated. Hopefully I will find some time to play with it again during the weekend. I bet I will end up giving it a lot of string follow, just to make it shoot :)

Yes, I believe the bow was seasoned with the tips touching. Why not?

It should perform Ok when dry and the string follow is kept to the minimum. Also, our historians please correct me, these bows are mostly post 17th c., when the firearms were already prevalent in combat. The looks could be more important than function.

Adam

Adam,
You are right in that the surviving bows are mostly seventeenth century and later. The proportion of sinew in the ears seems to vary considerably and it would be interesting to see if the lower sinew proportions were correlated with more effective bows.

McEwen was of the opinion that the best examples were comparable to Turkish war bows, but there was a very great variation in quality. It is possible that some of these bows were made to survive prolonged strung periods without warping and excessive loss of cast. Some of the heavy arrows I have from the same period are clearly for short range and possibly bows were being used as the equivalent of pistols by horsemen after the introduction of firearms.

Adam, sorry, my point was that if modern replications work improperly, then maybe there is something wrong with the replicas? I imagine that old used bows, that are fully curled up today, ought to have been pretty well made bows. Somehow the ancient bowyer did something that made the bow creep back close to it's pre-bent state. I think we should not discard the design untill we have made a bow that will do the same?

Perhaps one needs to start with a core that has "sals" that are already pretty reflexed, and then glue horn and sinew to it? That way, one would almost do it the same way as the Koreans, where the core is a circle even before sinewing. Maybe such construction would help the bow keep its reflex better?

But... I guess your replica with the huge reflex and having been put together by your experienced hands should be a good test of the design. If your bow was behaving poorly, there is no reason to think any other replica will behave better.

Yes, you are right that we should make more bows to see what actually happens. I would question though the (now) so common trust in the perfection of styles in terms of performance and utility. If a bow was little used and only for short range (as Bede suggests), why bother to perfect it?

I do not say the bows were useless. With so much sinew and glue however, one definitely needs dry weather to keep the reflex. At the same time, it is a matter of degree, not a radical improvement in performace. The same goes for the tip-touching, as-made reflex. It will help, but not hugely. And, given the difficulties in stringing the bows, I would expect the archers kept them strung for a long time, which would degrade the bows, even if made to perform.

I am certain these bows were made with great reflex. The old bows would not be so reflexed now if that was not the case. I recall one of these bows, a well used one, to have the tips crossed.

Adam

So, now the crab bow has been resting for about 10 months after sinewing, and I found some time to continue working on it. I put tepeliks on it yesterday, which it kept overnigth, and started bending it today. Through some hours of wrestling with it, filing and sanding away some of the belly sinew, it ended up with a reasonable tiller.

Still unstable as hell though... - which is probably somewhat due to two near-fatal slippages of the string, where one kasan twisted nearly 90 degrees out to the side trying to shred the string. It survived without a single crack though! I am convinced it would not have gone so well if the bow was not fully dressed in sinew.

To distribute the bend towards the kasans, I had to remove parts of the sinew on the belly, and also took away 0,5mm of the horn. Now it is about 12mm thick in the middle of the sal, while the original is about 13,5. I bet the paint on the original is somewhat thick, so it ought not to be too far off from the original anyway.

I am really not sure about this design. I used maple for the core, but I am starting to suspect that it might be better to make it from a stiffer kind of wood - because this one is behaving like jelly! It is soo bendy, in all directions. Which is obviously good and bad, as it seems to be able to take a thorough beating, but at the same time acts a little wildly.
OR, it might be that these bows were kept strung for really long times, so that they aquired lots of string follow, which made them stable enough. After full-draw this one has got perhaps 6-7 inches of overall reflex left, and still it is not behaving well.

I am also a little surprised by the draw weight. I have not yet measured it, but it is not as much as I first expected. Once it had been strung for a few hours it seems to have gotten a lot more flexible, and the draw weight just before the wall of stacking at full draw, might be around 80 pounds. I will give a proper number once measured.

But overall I am really happy that I managed to bring this one to full draw. The crazy full-draw profile is simply worth it :mrgreen:

...and the brace height: 11 inches! :shock: - and that's after I had made it bend more towards the kasans than the original. I could probably reduce it an inch though, once the bow stabilises a little more and I dare to let the string touch the kasans just a hint.


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:D nice.And good ponudage !

incredible form but working !
very good.
:shock:

Ivar - you're crazy! :D The bow looks unbeliveably cool!

Very nice job, congrats! I don't think that switching to another core wood would make any difference in stability; maybe increasing the amount of wood, expecially on the sides (more rectangular cross section), could be slightly beneficial. I guess that keeping it strung is the best way to stabilize it.
Francesco

Very good form, looks so good. Congrats.

Cem

After some of the problems your reported with the bow, particularly the instability, I looked back at some of your constructional photographs. The horn is much wider and covers more of the limbs than in the two dissections of these bows I have seen. I do not count the one in The Grey Goose Wing because I don't know where it came from. I wonder if the amount of horn is contributing to the lack of stability.

Incidentally, McEwen's reference to the performance of these bows was specific in that he compared the best crab bows with good Turkish war bows.

Thanks guys!

Francesco, you could be on to something there. I think I might have made the back of the bow a little more rounded than the original. I will make the next one with a more pronounced "D"-section.

Interesting thought, Bede. I looked back on the thread on Adams crab bow, and saw you mention horn width of down to 1/2 or even 1/3 of the total limb width. That's not much. I imagine such a bow would follow the string a lot, which surely would make it fairly stable. With prolonged stringing time and use such a bow would surely end up with close to no reflex, if my bow is representative for the willingness to follow the string.

I'm really intrigued with McEwens thought on the performance of these bows. Hopefully I will be able to shoot mine though a chronograph some time.

...on the other hand, the bow that Chris Boyton published here, has a fairly large amount of horn in it. - more than mine I think.

Now the bow has been braced for a six days, and the instability has finally given up. I shot some 25 shots with it today, and to my surprise my thumb was up for the job. - mainly because the bow had lost a few pounds. It is now 76 pounds at 30 inches and 56 pounds at 27 inches. That's at 50% RH. I haven't shot through a chrono yet, but the first impression is that it shoots ok, but maybe not better than a regular longbow I would say. It has a rather cool "thump"-sound though, and no hand shock. It's also quite practical as it can be hung diagonally over the chest without interferring much with arm movement.

I'm quite surprised that the weight is only half that of Adams bow at 27 inches, even though the thickness of the bending portion is pretty much the same - but I guess the lower amount of horn and grip/siyah angles make up for some of it. The force-draw curve of mine shows that it is starting to stack at 26 inches. Adam, maybe yours is starting the stacking even earlier?

Here is a picture of the bow braced and some seconds after unstringing. It crept back rather fast, but right after taking off the string, it had about 0,5" of reflex left. That's after shooting some 15 arrows from 28 inches draw. It's got some concentration of bend right out of the handle on the left side in the pictures, but dynamically thoughout the draw it seems to be acting better, so I'll probably leave it like that.



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:idea: very fine work! congrats!

Yes, the difference in draw weight can be attributed to the greater reflex in the grip and the siyahs and to the horn, which covers the whole belly in my bow (and can also be flatter as well). The grip reflex forces the limbs to bend further up and the bow stacks more. I did not chart the f-d curve, but when pulled on the tillering tree, the bow felt stacking past 22-23 inches and over 25 becomes pretty bad adding to the weight very fast.

The other thing is the drying of the bow - there is a difference betw. months and years.

How long is the string in your bow?

Adam

The string was 96 cm long when I did the F/D-curve and the brace height was 11 inches. After that I lengthened the string to 99cm, where the string knots now rest a little on the "kasans". The brace height is now 10 inches.

The initial impression with the string is that it is far too short for the bow, hehe.

I did measure the bending sections again, and they are in fact 11,4mm in the middle now. That ought to make up a little for the low weight too.



Going back to my confused thoughts on the design again, it still does not make any sense to me. If it is like Bede has suggested, that these bows were designed to stay braced for long periods, and that the dimensions of my bow is not too far off from the norm, it would seem like they had a rather low draw weight too. 56 pounds at 27 inches, used with arrows of 28-29 inches length, does not comform well to the general notion that most war bows in most cultures would have been drawing around 100 pounds.

Could it be that the mughal bowyers had some trick with the sinewing to make it stiffer and better at compressing? Maybe they used some glue-mixture that was better at compressing, and maybe the mango-wood performs better than maple in these bows?

What I'm thinking is that it is hard to believe that the very finely crafted original bow that I studied would have had similar performance to my bow. On the other hand, maybe this is simply the hard reality, that these bows did not have to evolve into being superb performers. Maybe a 60-70-pound bow did the job too? What was the arrow-protection like in the period? I suppose the bows were used along with gunpowder, which could indicate that most warriors did not have the equivalent of the western medieval plate armour, and maybe thick textile padding (which is very good for arrows) was not common either?

On second thoughts, I should not assume that the 2mm of belly sinew would not influate the draw weight of the bow. From 11,4 to 13,4mm could probably make the draw weight rise quite a bit.

I have long suspected that the horsebows used in the late 17th-early 18th centuries might not have been as heavy in draw weight as those of earlier periods. The growing use of better gunpowder weapons would have made those, in form of pistols and carbines, better for armour piercing. Armour itself would have been either very bullet resistant, and therefore arrow-proof, or have been lightened to the point that it was mostly protecting against shock weapons such as the sword only.

I think that bows, in the later period, would have been used mostly for skirmishing. They would still be useful at ranges well beyond pistol shot (at least most pistol ranges), and would probably be more accurate than carbines; as well as capable of faster repeat shots. There wouldn't be that much armour to contend with; and at closer ranges, pistols would be used to deal with armour.

That said, do keep in mind that even in its heyday, the composite bow would come in different weights. What is useful in dealing with soft-skinned animals, including tigers, wolves, maybe even bears, might not defeat armour. but would be easier than the heavy pulling bow.

So, the bow you have made, and the bow you imitated, might be reasonably typical.

McEwen told me he had made Mughal style bows is heavy weights conforming to the standard dimensions. He used normal glue mixes and construction methods that are well authenticated. My guess is that there may be a few techniques that modern bowyers will discover with experience and experiment. Don't stop at one bow.

Regarding 17th and 18th century archery, bows fitted into a niche that wasn't filled by firearms until the invention of the modern cartridge and breech loading carbines and pistols. Bows were primarily used by cavalry because of the difficulty of reloading muzzle loading guns on horse back. The Manchus in a gunpowder rich environment used very heavy bows because bows had become a short range weapon. They had to put down their man before he could retaliate. The Crimean Tatars, who eventually became the largest part of the Ottoman bow-armed cavalry also used heavy bows. In India, Ottoman style tactics with artillery within a lager of some sort were standard. Cavalry would have had many of the same pressures as in the west. The demise of archery was probably because they were using heavy bows and the training was becoming too onerous rather than the opposite.

I have Indian arrows that spine at over ninety pounds on a modern spine tester; they are not more than 7 mm in diameter. Shot with a thumb ring, I do not doubt they could be used on 120 lb bows.