35" Yew short bow - sinew failure - Lifting and hairline cracking

[2nocks]

For comparison,
The closest thing to it that I could find on the PA forum, was a little horn bow almost 35" bow posted by Chuck Loeffler in 2012
Here's the link >> (not sure if I'm allowed to post a link) but it's to this forum and I'm not trying to advertise anything. Mods please remove or chime in if this is not allowed. But pretty sure he's talking about the lower bow on the rack, but the top bow in the pic looks like a very similar shape to this U-shape yew bow from the coast. maybe my tiller should aim in this direction though.

http://204.57.114.190/smf/index.php?topic=35859.0

[DC]

This is a bit off topic but in 1792 Capt Vancouver was in the waters in front of my house. This made me wonder if it was a local bow. I looked up his life and in the 1770's he was on Capt Cook's ship. I would think that anything collected on a trip would be credited to the Captain but I'm not sure. I couldn't find out in what capacity Vancouver was serving on Cook's ship in order to get credit for collecting the bows. Have to find out where Cook went on his 1770 trip.

[2nocks]

This is a bit off topic but in 1792 Capt Vancouver was in the waters in front of my house. This made me wonder if it was a local bow. I looked up his life and in the 1770's he was on Capt Cook's ship. I would think that anything collected on a trip would be credited to the Captain but I'm not sure. I couldn't find out in what capacity Vancouver was serving on Cook's ship in order to get credit for collecting the bows. Have to find out where Cook went on his 1770 trip.

This is very on topic !
I didn't know Vancouver served on Cook's ship. Thanks for digging that out.
My previous post was wrong on the date (I had confused it with Cook 1770's) . -these bows are indeed attributed to Captain Vancouver on his 1790's voyage.

[DC]

Wikipedia has a pretty detailed account. Vancouver's 1792 trip would put those bows in my general area. I've never seen any bows at all from this area. I don't know if there are any in the provincial museum. I'll have to look and see what I can find. I doubt if any have survived as it's very wet here and things rot in a few years.

[DC]

He came by way of Australia and made North American landfall in California and explored to Alaska. The bows could have come from anywhere. His "A Voyage of Discovery to the North Pacific Ocean and Round the World in the Years 1790-95" covers the whole trip in three volumes. I suppose there is a possibility that he commented on where he got the bows.

[2nocks]

He came by way of Australia and made North American landfall in California and explored to Alaska. The bows could have come from anywhere. His "A Voyage of Discovery to the North Pacific Ocean and Round the World in the Years 1790-95" covers the whole trip in three volumes. I suppose there is a possibility that he commented on where he got the bows.

DC > Yeah actually reading those journal notes (and some of the journal entries of his fellow crew members) indicates that bows and arrows were popular barter items with the crew of the HMS Discovery - Vancouver's ship. I thought it would be super cool if I could actually find the day or the record in his journal that he likely traded for the Miwok bow or the Yurok bow (?) which are two other highly identifiable bows in the collection by their hook and bent tab nocks. And then go digging for a journal entry that mentions the other 3 bows. But the journal is so littered with entries that mention trading for hunting gear and tackle, (considered by the crew as a sign of peace and willingness to trade, when the weapons were laid on the ground in front of them), but what's more amazing is actually how come only 5 of these bows ended up in museum collections in England. The likelihood that most of them were given away as gifts to friends or noblemen men and their kids to play with is actually a theory that's been floated around. Vancouver's crew must have also been well fed. Because when you read Captain Cook's account of their bartering 20ish years earlier, they were always hungry for venison and dried fish and mentioned that they traded copper items and fish hooks to obtain (better) food.

My best guess (but I'd love to be shown or told otherwise!) is that these particular two bow came from the area of Port Discovery / Puget Sound and might be Clallam (Klallam) of origin.

[bradsmith2010]

very cool,,

[DuBois]

Could it be the glue that cracked? If too much glue is used the glue can crack and if that is the case I don't think it is a real problem. I don't know why the wood would crack under the sinew/glue backing.

1+
I probably need glasses but I'm having difficulty seeing the problem😕

Been a while since I posted much here but I do remember a thread by Pat M. I think that was about wrapping and then heating sinew to squeeze out excess glue and get a glassy surface.
Maybe you could scrape a bit down into sinew, apply a thick sizing coat of glue, apply a new sinew layer and then give the wrap and heat method a try.
Might help if you really think it's not right as is.

[loefflerchuck]

The photo of the museum bows is not the best, but on the middle bow it looks like the tips are sinew past the wood. That and the rest of the shape would mean these bows were picked up in the San Francisco bay area and are Miwok origen. A frontprofile would help. Were the bows 1.5-" wide? These bows would have picked up more reflex than they once had from being unstrung that long on a thin wood frame under the sinew. If it were not from the Vancouver expedition I would say it must be a interior horn bow. You mention porcupine quillwork? That puts it in the Northern plains/plateau area where horn was used.? I have never heard of quillwork on west coast bows.
 
Your asking a lot out of a wood bow. The reflex profile is one for horn. I hear the Perry reflex theory, but the sinew gives the wood a permanent deformity with that much reflex so it is still under a bit more compression that without. The wood is not acting as a stabilizing core as in a composite horn bow, but as a belly and core. Horn can handle around 5x more compression than wood. Not to mention it is going to be pretty unstable when it's braced.

 You did a great job on the bow. That much sinew and reflex you need to make sure your glue is the best and there is no contamination between layers and properly sized for each. I would not attempt this bow with wood belly

[2nocks]

The photo of the museum bows is not the best, but on the middle bow (referring to bow "Van 6") it looks like the tips are sinew past the wood. That and the rest of the shape would mean these bows were picked up in the San Francisco bay area and are Miwok origen. A frontprofile would help. Were the bows 1.5-" wide? These bows would have picked up more reflex than they once had from being unstrung that long on a thin wood frame under the sinew. If it were not from the Vancouver expedition I would say it must be a interior horn bow. You mention porcupine quillwork? That puts it in the Northern plains/plateau area where horn was used.? I have never heard of quillwork on west coast bows.

Just going to try and provide some more details and reply to a few questions that were raised here - because I am glad @ leofflerchuck points out some anomalies with the quill work and shares more his experience with west coast and plains bows.

- I've got another grainy pic of a front profile that I'll post here. >> Yes the bow at the grip is exactly 1.5" wide (x 13.5 mm thick)*not sure if this includes the leather thong or if the leather was subtracted. I’m guessing subtracted. . Mid-limb it goes down to 1 3/8" (x 10mm thick) and at the tips it's 9/16" (x 8.5mm thick)

- I'm glad you point out that quill work on a west coast bow would be quite an anomaly. And that a bow of this profile should probably be in horn. These are things that have been mystifying me, but I admit I never even considered that it may be of Northern plains/plateau origin because it was definitely picked up in the Vancouver expedition. But that's not to say it couldn't have been traded west to the coast or that the coastal people made a wooden copy of a horn bow (of inferior quality) to pawn to the English for things of more value to them. Or maybe the plains people made an inferior copy of a horn bow to trade to the coastal people who then passed it off to Vancouver. 

-You raise a good point though, what's this yew wood bow doing with quills and the profile of a horn bow, allegedly from the region of Puget Sound ?

The bow is wood and not horn. Some early sources like the museum catalogue and a few early academic papers that detail these two little U-shape bows say it's cedar - but I think in the 1800 and 1900's the English might have just called or thought any west coast wooded bow to be made of cedar. But a good friend of mine (and bowyer) drew / surveyed this bow in the 70's or 80's and said he thought the wood is yew. I've never handled it first hand. I'm working off of his photos and drawings. Not sure I would know what to look for to tell the difference between (incensed) cedar and yew anyway as I've never worked with cedar. Is it more yellowish lighter colour than the deep aged reddish hue of yew ?

I don't want to bore anyone with more details about the research and history of these two bows, but if anyone is interested just PM me or if there is more general interest or curiosity just ask me to post more info here. I'd be happy to share what I've found. For now I'll put up the other grainy pics cus they do show the wood and they do show the quills.

[2nocks]

I also have some results to share and post.
yesterday was my first day wrestling with this thing and actually getting a string on it.
I was tricked by the sinew. I have two other west coast bows that pull aprox 55 and 60 lbs at 18" draw
(18" is my preferred draw) and this little sinew bow felt like it was 70-80lbs trying to just wrestle it to get the string on. So I thought I had plenty of margin to tiller from there. But once the string was on and it curved over to the other side the way it should be braced it softened up much to my surprise and disappointment like a springy noodle. Way too much for my liking. and by the time I tillered the rest of the bow to avoid the potential hinging spot that I had originally flagged in one of the earlier photos with the yellow circle, it was too late for this to be a heavy puncher. Overall, I'm about 1mm under dimension at the grip and 0.5 mm thinner than the original mid-limb. Which is too bad cus after all this effort, I would have loved this bow to be about 10-15 # heavier. It also feels sluggish and slow, but probably cus it has more sinew than it needs. If I were to do a second attempt I'd give it less sinew and more wood. and not be scared into thinking the yew can't handle compression in this extreme recurve design at thicker ratios of wood to sinew. So far this isn't showing signs of fatigue - though if I were to shoot 100 times at 20" draw, which I might attempt after learning what I can about it at 16-18" first.. then maybe I would start to see some chrysals.
There are no compression frets or signs of failure and I did end up with a working shooter. So I guess that's a small success worth celebrating and improving upon the next time.

@ loefflerchuck - I now see what you mean by totally unstable in brace position !

here's my results.
Fresh strung in the morning and after use for about 10-15 shots:

16# 10"
20# 12"
24# 14"
28# 16"
32# 18"

it also picked up a fair bit of 'set', whereas I was building it with about 20" spread between the tips (thinking it would relax or set to 22-23" it has now set to 26". perhaps the originals reflexed more over disuse and time, but I'm also thinking a thicker wood might have kept it's shape more. 


*edit > tried longer draws and it'll pull 38-40# at 20-20.5" Arrows are pretty zippy (no chronograph to actually measure) but I'm starting to see penetration in the target similar to depths that I see with my heavier bows. So at least potentially this little thing can deliver. Thanks to a kind member who pointed out that I should try with a shorter / lighter arrow

I think this bow would be a screamer with a bit more meat on it's bones. And about 15# heavier.
Worth trying to make again.

[DC]

Very cool!! Shoot the heck out of it while you're building a replacement and see if it chrysals. Report back here

PS The belly seems quite flat. I'm wondering if that's why you're not seeing chrysals----yet?

[loefflerchuck]

I'm not bored. Thanks for the extra photos. The top photo, the second from the bottom is a sinew knocked bay area bow probably incense cedar. That indeed looks like plaited quillwork. I'm sure it could have come from Puget Sound. I don't think I've never seen these bows. I know Vancouver picked up the only surviving sinew backed Chumash bow. Probably of juniper from southern California. I'm not sure if he picked up any bows further south of that,  but he worked his way up the coast and we owe him a thanks for collecting these treasures for us to study today. Keep in mind this was a time before firearms were in use by natives in the west and thus probably the peak of bow and arrow technology.

 myself and others would tell you that 5" of reflex + or _ depending on length is optimal. More than that has diminishing returns on performance. Overworked wood gets limp, or in the desert here brittle.

[bradsmith2010]

maybe the profile of that bow was not all about performance
but somehting to do with the bow maker showing what he was able do,,
but until I could see some chronograph test,, I would not really know if going to that much reflex had any bennefit,,
going past the 5 inches might not gain any performance, but it sure was pretty and that might be part of it,, I think,,,,but just guessing,,
I have never made or had a chance to shoot a bow like that,, but sometimes I think they did stuff for a reason that is not apparent,,,,something important to the bow maker or archer,,