crab bow (nearly) strung
As the crab bows have generated some interest, I am posting a strung crab to show the insane bends in the sals. This bow is an example of an extreme case of "crab-ness" with the max. recurvature at the siyahs. The brace here is 8 3/4 in and may have to go up a little for the string to completely clear the kasans (as it should). The bow still needs some tiller touch-up and the sinew on the belly.
These bows remind me of those mythical and fanciful weapons coming out of India and, in my opinion, are too late an invention to be of use during serious combat. Maybe for show or target, but will stack badly.
Adam
These bows remind me of those mythical and fanciful weapons coming out of India and, in my opinion, are too late an invention to be of use during serious combat. Maybe for show or target, but will stack badly.
Adam
:shock: Hark ! As long as this had not been reproduced, I'd not believe it could work. Looks like the stress-test of a bowyer's skill.
thank you for posting
& keep us updated on the performance
8)
thank you for posting
& keep us updated on the performance
8)
Adam; A very nice work! The difference between this and my crab bow is that the grip on mine is straight and the sharp bends occur just out from the grip. The bend at the elbow is only slightly less and the tips are a little less bent also. But all in all I find yours totally authentic.
These bows were, however, used in battle. Pant has a good deal of info on them. They were the exclusive property of knights and such. For instance he tells how a war elephant would have a little box type tower on top with 5 archers with these bows inside.
Bows were the preferred battle weapon until the British period in 1857 and authentic bows date to before this time. This is how so many of them came into the provenience of Europeans.
Excellent reproduction.
These bows were, however, used in battle. Pant has a good deal of info on them. They were the exclusive property of knights and such. For instance he tells how a war elephant would have a little box type tower on top with 5 archers with these bows inside.
Bows were the preferred battle weapon until the British period in 1857 and authentic bows date to before this time. This is how so many of them came into the provenience of Europeans.
Excellent reproduction.
Adam, great work, these crabs don?t need to much horn.
Again I?m asking about the design: why such complicated?
Michael
Again I?m asking about the design: why such complicated?
Michael
"...But all in all I find yours totally authentic. .." This bow is a replica of an old bow I have.
The complicated shape is probably a matter of fashion for the most part. I have a problem to to see important engineering considerations in this design. Note the bow is actually very short when strung once the sals are bent. It will stack probably worse than some of the flight bows. The only conceivable advantage are the wide limbs, which should store more elastic (recoverable) energy than bows with narrow limbs. But the efficiency will be low with those big siyahs. All subject to future testing of course.
Adam
The complicated shape is probably a matter of fashion for the most part. I have a problem to to see important engineering considerations in this design. Note the bow is actually very short when strung once the sals are bent. It will stack probably worse than some of the flight bows. The only conceivable advantage are the wide limbs, which should store more elastic (recoverable) energy than bows with narrow limbs. But the efficiency will be low with those big siyahs. All subject to future testing of course.
Adam
Looking forward to it! :DAdam Karpowicz wrote:
All subject to future testing of course.
Awesome!!
Do you think it would become stable at a lower brace height if the bending was concentrated closer to the grip? I've studied two original crabs, and both were not bending in the outer part of the sal. This seems to have been quite common. The laquer was only cracked in a 10-15cm long area on the belly of these two I saw.
Do you think it would become stable at a lower brace height if the bending was concentrated closer to the grip? I've studied two original crabs, and both were not bending in the outer part of the sal. This seems to have been quite common. The laquer was only cracked in a 10-15cm long area on the belly of these two I saw.
Ivar, it would be the opposite - bending close to the grip will raise the brace height, because more bending would be required to clear the kasans in the extreme crab bow. Maybe that was the case with these bows, I do not know. In the original bow the cracking goes all through, most at the centre of sals (where one limb actually broke).
Adam
Adam
Adam,
The bows I have look as they would bend closer to the kasan/sal boundary than your reproduction. I also notice that you have used exposed horn. Again the bows I have examined have narrow thin horn bellies with the belly on either side filled with longitudinally laid sinew. The whole is then covered with a fine layer of transverse sinew, metal leaf and paint.
I am guessing that a bow with a horn strip only a half to a third of the width of the belly would be more flexible than a bow with a full width strip.
Regarding performance, I was recently talking to McEwen and he said crab bows he had made in the traditional manner compared favourably to Turkish and Persian war bows though not to flight bows. I did not ask about the horn, since I remember there were two methods. In one a thin, narrow strip of horn was used on each limb while in the other the width of the belly was covered by multiple strips. In the first kind, much of the shape of the kasan was built up from sinew and the belly as well as the back. In the second kind, there was more wood in the kasan.
The bows I have also do not seem the have the abruptness of reflex near the grip that yours has. I realise from what you have written that your reproduction is closely based on an original, but how typical is it? I have examined about 20 crab bows in person and more in photographs and the grip reflex when present seems more gradual though a small proportion were the same as yours. This might be an artefact of use. One bow I have has completely opened out so that it looks like a bracket (]). I have been told by at least one bowyer that he has built in as much reflex near the grip as you did and had it disappear in bracing the bow.
Knowing your constructional methods and the robustness and efficiency of your bows, it will be interesting to see how it performs. Most of the high grade Indian arrows I have are are between 27.5 and 29 inches which suggests a draw length.
I agree with your about the string position on the belly of the kasan, but I must point out that Dr Grayson thought the string laid on the kasan for some distance. I think that this was the result of gut cored strings being left on the bow for too long. I mentioned this and he pointed out that he had shot bows in that condition without the string slipping off. I saw this meaning that he was a very stable bowman and the bows were more stable than I thought.
Most early Moghul paintings show bows more similar to Persian bows than crab bows. The manuscripts talk about four bow shapes, including the chahar kham which had a solid horn belly under the paint. I found bows looking more like crab bows in late eighteenth century paintings and later in the early nineteenth century.
The bows I have look as they would bend closer to the kasan/sal boundary than your reproduction. I also notice that you have used exposed horn. Again the bows I have examined have narrow thin horn bellies with the belly on either side filled with longitudinally laid sinew. The whole is then covered with a fine layer of transverse sinew, metal leaf and paint.
I am guessing that a bow with a horn strip only a half to a third of the width of the belly would be more flexible than a bow with a full width strip.
Regarding performance, I was recently talking to McEwen and he said crab bows he had made in the traditional manner compared favourably to Turkish and Persian war bows though not to flight bows. I did not ask about the horn, since I remember there were two methods. In one a thin, narrow strip of horn was used on each limb while in the other the width of the belly was covered by multiple strips. In the first kind, much of the shape of the kasan was built up from sinew and the belly as well as the back. In the second kind, there was more wood in the kasan.
The bows I have also do not seem the have the abruptness of reflex near the grip that yours has. I realise from what you have written that your reproduction is closely based on an original, but how typical is it? I have examined about 20 crab bows in person and more in photographs and the grip reflex when present seems more gradual though a small proportion were the same as yours. This might be an artefact of use. One bow I have has completely opened out so that it looks like a bracket (]). I have been told by at least one bowyer that he has built in as much reflex near the grip as you did and had it disappear in bracing the bow.
Knowing your constructional methods and the robustness and efficiency of your bows, it will be interesting to see how it performs. Most of the high grade Indian arrows I have are are between 27.5 and 29 inches which suggests a draw length.
I agree with your about the string position on the belly of the kasan, but I must point out that Dr Grayson thought the string laid on the kasan for some distance. I think that this was the result of gut cored strings being left on the bow for too long. I mentioned this and he pointed out that he had shot bows in that condition without the string slipping off. I saw this meaning that he was a very stable bowman and the bows were more stable than I thought.
Most early Moghul paintings show bows more similar to Persian bows than crab bows. The manuscripts talk about four bow shapes, including the chahar kham which had a solid horn belly under the paint. I found bows looking more like crab bows in late eighteenth century paintings and later in the early nineteenth century.
Adam:
Great work. What is the thickness ,length and width of the sal and thickness of the horn? Balance looks very good, what about stability?
Cem
Great work. What is the thickness ,length and width of the sal and thickness of the horn? Balance looks very good, what about stability?
Cem
Bede,
I agree with you about the variability in the shape of the bows. I have seen quite a few with less reflex in sals close to grip, on the other hand some of the bows (including mine, which has even more reflex than the replica)) had more reflex there. Ultimately, the strung shape, depending on the relative thickness of limbs in different sections, determines the behaviour of the bow together with the reflex. I remember one bow as you describe with no reflex at the grip, probably reduced from use, or maybe made that way from the start. A bow with more reflex, but with limbs thinner at the grip, will look just the same when strung as a bow with less reflex, but with the limbs thicker there. It is obvious these bows were not factory made and the inner construction could vary somewhat as well.
The horn in this bow will be covered with sinew and I can still remove more horn from the sides. It will drop the weight a little probably, on the other hand, if the overall thickness of the bow sans the belly sinew is similar, then the stiffness of limbs will not change too much.
I have not seen any signs of contact of the kasan belly with the string in these bows, only a dent or some chipped paint at the base of the tips. This tell me the string did not touch the kasan belly, since the impact would certainly leave a mark. I understand it is tempting to use a longer string and make the bow a better performer. Unfortunately this is not the case. I am not sure I even want to ever try testing it and see no reason why it could be comparable to Tatar or Turkish bows. Perhaps with the longer string contacting the kasans?
Cem - the bow is about 4cm wide and now 12+mm thick in the middle of sal. With sinew it will gain 1 to 1.5mm in thickness to match the old one. I pulled the bow to 23 inches (80+lb) now and found, as expected, severe stacking beyond that. I estimate the bow would be close to 100lb at full 28in draw, possibly 90lb in the hot weather of India. And, given the difficulties in stringing the bow, I suspect they were left strung for weeks. The wide limbs make the bow quite stable, but not more than Turkish. Those sharp bends and the string so close to kasans reduce stabilty.
Adam
I agree with you about the variability in the shape of the bows. I have seen quite a few with less reflex in sals close to grip, on the other hand some of the bows (including mine, which has even more reflex than the replica)) had more reflex there. Ultimately, the strung shape, depending on the relative thickness of limbs in different sections, determines the behaviour of the bow together with the reflex. I remember one bow as you describe with no reflex at the grip, probably reduced from use, or maybe made that way from the start. A bow with more reflex, but with limbs thinner at the grip, will look just the same when strung as a bow with less reflex, but with the limbs thicker there. It is obvious these bows were not factory made and the inner construction could vary somewhat as well.
The horn in this bow will be covered with sinew and I can still remove more horn from the sides. It will drop the weight a little probably, on the other hand, if the overall thickness of the bow sans the belly sinew is similar, then the stiffness of limbs will not change too much.
I have not seen any signs of contact of the kasan belly with the string in these bows, only a dent or some chipped paint at the base of the tips. This tell me the string did not touch the kasan belly, since the impact would certainly leave a mark. I understand it is tempting to use a longer string and make the bow a better performer. Unfortunately this is not the case. I am not sure I even want to ever try testing it and see no reason why it could be comparable to Tatar or Turkish bows. Perhaps with the longer string contacting the kasans?
Cem - the bow is about 4cm wide and now 12+mm thick in the middle of sal. With sinew it will gain 1 to 1.5mm in thickness to match the old one. I pulled the bow to 23 inches (80+lb) now and found, as expected, severe stacking beyond that. I estimate the bow would be close to 100lb at full 28in draw, possibly 90lb in the hot weather of India. And, given the difficulties in stringing the bow, I suspect they were left strung for weeks. The wide limbs make the bow quite stable, but not more than Turkish. Those sharp bends and the string so close to kasans reduce stabilty.
Adam
Adam,
I agree with what you say. I was thinking of a longer string as well, but not at the expense of laying along the kasans. What I thought was that a bow that bent closer to the kasan eye to maintain the same overall position of the whole gosha in relation to the string while reducing the brace height. It was my opinion that many bows when strung without tepeliks often ended bending closer to the grip than intended. While I know you would use the best method for stringing the bow, I also know that you can customise the shape by applying pressure during the initial period of stringing.
The only bows I have seen that have the string laying on the kasan were ones that had been strung for decades. There was no indication of impact compression on the belly of the kasan so I do not think they were shot with strings set up that way. I still believe that the strings stretched with age, whether because the materials elongated or because the knots tightened or slipped. However, if the strings are the right length, it could be because the limbs were meant to bend closer to the kasan and be straighter near the handle. I assume that that would require a bow that was somewhat thinner in the few inches before the sal-kasan transition. that is exactly the place where, in the bows I examined, the splice was.
I forgot to mention in my first post that the bow looks beautiful braced, if a bit scary.
I agree with what you say. I was thinking of a longer string as well, but not at the expense of laying along the kasans. What I thought was that a bow that bent closer to the kasan eye to maintain the same overall position of the whole gosha in relation to the string while reducing the brace height. It was my opinion that many bows when strung without tepeliks often ended bending closer to the grip than intended. While I know you would use the best method for stringing the bow, I also know that you can customise the shape by applying pressure during the initial period of stringing.
The only bows I have seen that have the string laying on the kasan were ones that had been strung for decades. There was no indication of impact compression on the belly of the kasan so I do not think they were shot with strings set up that way. I still believe that the strings stretched with age, whether because the materials elongated or because the knots tightened or slipped. However, if the strings are the right length, it could be because the limbs were meant to bend closer to the kasan and be straighter near the handle. I assume that that would require a bow that was somewhat thinner in the few inches before the sal-kasan transition. that is exactly the place where, in the bows I examined, the splice was.
I forgot to mention in my first post that the bow looks beautiful braced, if a bit scary.
Incredible form... I look forward to pics in full draw.
I have looked at the pictures I have of a dissected crab bow. In the area immediately before the sal to kasan transition, the horn layer has thinned to about 2 mm or less and there is the same thickness of sinew on the belly as on the back. To the naked eye it looks like the belly sinew = wooden core = back sinew with a sliver of horn on the belly side of the core. Most of the horn thinning takes place after the splice which is entirely in the sal.
Wow, that look is really dangerous... Makes me want to string that crab bow trial of mine again. But from excessive heat one of the ears is probably damaged (heard a cracking sound when bending). Have to recheck this.
Adam, great work! But the bow looks as if it is already so stressed from bracing that drawing it to arrow length would put serious damage to the bending parts... Will the horn survive this? I?m curious about further drawing this bow! It is obvious that such design doesn?t make much sense, so why did they do it?
- Are you absolutely sure that this extreme knee angle considerably under 90? is the same as in an original?
- If so, could it be that in original bows this angle increased by drying for over 100 years?
JJ
Adam, great work! But the bow looks as if it is already so stressed from bracing that drawing it to arrow length would put serious damage to the bending parts... Will the horn survive this? I?m curious about further drawing this bow! It is obvious that such design doesn?t make much sense, so why did they do it?
- Are you absolutely sure that this extreme knee angle considerably under 90? is the same as in an original?
- If so, could it be that in original bows this angle increased by drying for over 100 years?
JJ
JJ,
The bow will not be over-stressd at full draw. Since the limb thickness is about 1.2cm now (to increase to 1.3 with sinew on belly), the min. radius of bending will be (1.2/2)/0.10 = 6 cm, where the 0.10 is 10% max strain (actually sinew and horn can withstand more than that). Even with the belly sinew the min. radius will be only about 8.5cm.
The prototype of the bow is the one pictured on page 19 of my book - some differences, but the recurvature is very close. Note the original had most bendng in the middle of the sals where it shows some string follow, not close to the kasans. This means the original's brace height was probably even greater than in the replica.
As to drying. I do not think it could be possible with the thickness of the bow at the bend. Even if possible, I would expect serious damage to the paint there, but the finish is completely intact, there is only cracking of paint in the bending sections. If the bow was recurving itself so much, then the paint on the back side would come off.
Adam
The bow will not be over-stressd at full draw. Since the limb thickness is about 1.2cm now (to increase to 1.3 with sinew on belly), the min. radius of bending will be (1.2/2)/0.10 = 6 cm, where the 0.10 is 10% max strain (actually sinew and horn can withstand more than that). Even with the belly sinew the min. radius will be only about 8.5cm.
The prototype of the bow is the one pictured on page 19 of my book - some differences, but the recurvature is very close. Note the original had most bendng in the middle of the sals where it shows some string follow, not close to the kasans. This means the original's brace height was probably even greater than in the replica.
As to drying. I do not think it could be possible with the thickness of the bow at the bend. Even if possible, I would expect serious damage to the paint there, but the finish is completely intact, there is only cracking of paint in the bending sections. If the bow was recurving itself so much, then the paint on the back side would come off.
Adam
Hello Adam,very interesting bow,nice work(as always).Was it difficult to "tame"?I bet it would tend to twist like crazy the very first times you bend it.I think less extreme crab bows are quite fast,I would like to make one someday:they are attractive.Have you got some pictures of the core(at the knee in particular) before gluing?Your book is really brillliant:it covers every detail in a very scientific way.I started making bows again(after a too long pause) thanks to it.Congratulations.
Bye
Francesco
Bye
Francesco
I an sorry Francesco, I have not made any pictures. The core in this bow was a little thicker than in some of the originals - less sinew, more wood. The splices were similar.
Adam
Adam
Adam,
Are your tips and kasan ridges both at about 1.5cm thickness?
Matt
Are your tips and kasan ridges both at about 1.5cm thickness?
Matt
Matt - the total thicknes of kasans was 20+mm and the tips a little less.
Adam
Adam
What were they at pre-sinewing but post shaping sans the horn?
I do not remember (I made the bow a few years ago). Prob. 4-5mm less.
Adam
Adam
ok last question about the kasan ridges: what are their length?
beautifull bow, expert work, you really got the perfect crab bow form, with a nice even tiller and looks to bend in the right places.
The only thing I dont like about crab bows is the name 'crab' sounds kind of derrogatory to my ears? I think they should have a better name!!!
The only thing I dont like about crab bows is the name 'crab' sounds kind of derrogatory to my ears? I think they should have a better name!!!
so call it Mughal - like Mongol :-)
Btw is this a correct linguistic explanation ?
Persian ‏مغول‎ mughul means ?Mongol?
Gurkhan (‏گوركانى‎) = Mughal King comes from mongolian k?r?g?n = ?brother-in-law", pointing towards the relation with Chinggis Khan's family
?Mog(h)ulistan? = Tschagatai-Khanate, home of Tamerlane
Btw is this a correct linguistic explanation ?
Persian ‏مغول‎ mughul means ?Mongol?
Gurkhan (‏گوركانى‎) = Mughal King comes from mongolian k?r?g?n = ?brother-in-law", pointing towards the relation with Chinggis Khan's family
?Mog(h)ulistan? = Tschagatai-Khanate, home of Tamerlane
Any news on this bow? I'm intrigued by the stability of the design. Your bow sems to have a fair amount of horn, which according to the rumor would make it very unstable while keeping a lot of reflex. Got any thoughts on these bows ability to keep reflex while being used, versus stability? What feature of the construction in these bows would you say gives them stability?
The rumour comes from Kani (If recall this detail correctly), which is true, since the horn, together with sinew both have the modulus (stiffness) lower than wood, so more of each would make a bow softer. Since the sinew layer was nearly always the same thickness in all Turkish bows, the horn was the culprit for them.
The crab bows have lots of sinew and this will make them less stable as well, unless the humidity was lower for the sinew to get stiffer. I think the low humidity plus the greater thickness of the limbs overall would make the bows more stable.
I strung my crab with some difficulties again (see pic) and decided to do a bit of more drastic heat treatment of the sals to force more bending close to siyahs. It helped and I saw old bows with similar bending before.
The bow stacks horrible beyond about 21-22in. I drew it to 26 so far - nearly 100lb! Anyway, this design is the worst imaginable with the un-necessary and excessive recurve at the siyahs, which as a result make the bow behave as a shorter bow than it is. And the high brace (8.5in here) reduces the power stroke. I can not help thinking of those exaggerated fantasy weapons made in India (swords and such)...
Adam
The crab bows have lots of sinew and this will make them less stable as well, unless the humidity was lower for the sinew to get stiffer. I think the low humidity plus the greater thickness of the limbs overall would make the bows more stable.
I strung my crab with some difficulties again (see pic) and decided to do a bit of more drastic heat treatment of the sals to force more bending close to siyahs. It helped and I saw old bows with similar bending before.
The bow stacks horrible beyond about 21-22in. I drew it to 26 so far - nearly 100lb! Anyway, this design is the worst imaginable with the un-necessary and excessive recurve at the siyahs, which as a result make the bow behave as a shorter bow than it is. And the high brace (8.5in here) reduces the power stroke. I can not help thinking of those exaggerated fantasy weapons made in India (swords and such)...
Adam
picture
Cool 8) So a high amount of wood in these might be the factor to pay attention to in making them behave stable.
I think your "all show, no go"-idea about these bows is pretty much it. Especially your bow seems to show this. I guess mine, with the 10-11" brace height also shows that it could not be a type of bow designed with mainly performance in mind. - however, I wonder if the geometry of these bows make them rather good with light arrows, in spite of the heavy "kasans". I'm curious to test-shoot it, but mine is still too unstable to dare to loose some arrows.
My bow is now braced and strapped to the workbench, where it will stay for a week. After staying braced for a week I hope it will be ready to give off a force/draw-curve and maybe some test shots. Like yours it seems to want to stop at 27-28 inches. - which I guess indicates that it can not be a great shooter with a only 17-inch powerstroke.
Is there any chance to get a report on how much overall reflex your bow has kept after staying braced a while and having been drawn some times? Adding to the "performance-disappointment" with the design is the rather large string follow mine showed.
What design-pressures that shaped these bows is quite baffling to me. - other than the rather large show-off factor, hehe.
I think your "all show, no go"-idea about these bows is pretty much it. Especially your bow seems to show this. I guess mine, with the 10-11" brace height also shows that it could not be a type of bow designed with mainly performance in mind. - however, I wonder if the geometry of these bows make them rather good with light arrows, in spite of the heavy "kasans". I'm curious to test-shoot it, but mine is still too unstable to dare to loose some arrows.
My bow is now braced and strapped to the workbench, where it will stay for a week. After staying braced for a week I hope it will be ready to give off a force/draw-curve and maybe some test shots. Like yours it seems to want to stop at 27-28 inches. - which I guess indicates that it can not be a great shooter with a only 17-inch powerstroke.
Is there any chance to get a report on how much overall reflex your bow has kept after staying braced a while and having been drawn some times? Adding to the "performance-disappointment" with the design is the rather large string follow mine showed.
What design-pressures that shaped these bows is quite baffling to me. - other than the rather large show-off factor, hehe.
After about a week strung and drawn a few times (110lb at 27in, 60%RH), the immediate unstrung reflex is 2in. If I did not do the extra heat bending on the limbs close to kasans, it would be about 5-6in (not too far from the fresh after tiller). I could have thinned the sals there instead of doing the heat corrections to keep the reflex, but then the thinner limbs would be less stable (and the bow would probably stack even more), so I opted for the heat.
I was tempted to test the bow and compare with other styles, but it would not be a fair comparison at this time (high RH, strung so long). Maybe some other time once the belly sinew is in place.
Adam
I was tempted to test the bow and compare with other styles, but it would not be a fair comparison at this time (high RH, strung so long). Maybe some other time once the belly sinew is in place.
Adam
Thanks! - those are some valuable numbers for my mind to adjust to. The amount of string follow is quite surprising, considering the curled up shape of some original bows. But I guess this is to be expected from this design then, after similar reports from three bows. Alex Wittenaars bow being the third.
Do you think it would be possible to make these bows with a tip-touching core before glueing the horn? To me it seems like most composites only creep back to the shape the horn+core had before sinewing. With the horn thoroughly covered by sinew, there might also be less of a problem with the horn popping off because of the glued in reflex in the bending portions.
Historically I thought stringing time of more than a week would have been quite common for most composites? What air humidity could the crab bows mainly have been used in. Bede?
Do you think it would be possible to make these bows with a tip-touching core before glueing the horn? To me it seems like most composites only creep back to the shape the horn+core had before sinewing. With the horn thoroughly covered by sinew, there might also be less of a problem with the horn popping off because of the glued in reflex in the bending portions.
Historically I thought stringing time of more than a week would have been quite common for most composites? What air humidity could the crab bows mainly have been used in. Bede?
I do not see the string follow to be so extreme as you suggest. Right now, afte a day and a half, the bow returned back to about 6 inches of reflex. And, if the heat treatment I used on the kasans was not done, the bow would now have about 9-10 inches of reflex.
In bows having so much sinew as these ones, I actually expect to see more reflex after years of storage (unstrung of course). It is because the sinew with glue are the most "reactive" materials in a bow. Both react to the humidity changes more than horn or wood. The reaction, when the stress is removed, is directed to contract the sinew layer as the former strains are released - both (and especially so) in high humidity and in higher temperature. So, after years of fluctuations the bows re-acquire a lot of reflex, possibly even more than first tillered.
I think it is possible the bows were made with tips touching from the start, similarly to the Korean bows, because the stresses in the limbs are not very high in the relatively thinner limbs and longer sals.
Adam
In bows having so much sinew as these ones, I actually expect to see more reflex after years of storage (unstrung of course). It is because the sinew with glue are the most "reactive" materials in a bow. Both react to the humidity changes more than horn or wood. The reaction, when the stress is removed, is directed to contract the sinew layer as the former strains are released - both (and especially so) in high humidity and in higher temperature. So, after years of fluctuations the bows re-acquire a lot of reflex, possibly even more than first tillered.
I think it is possible the bows were made with tips touching from the start, similarly to the Korean bows, because the stresses in the limbs are not very high in the relatively thinner limbs and longer sals.
Adam