I like Chinese (Bows)

[GrahameA]

Morning All

A short bow build. Wait for part II - The Rebuild.

I like Chinese/Asian Bows. However, nearly all of the bows you see are short and not all Chinese bows are short little bows.. Mentioning this one day to Greybeard he suggested we (I) build one with him supplying Guidance and Coffee. And a BIG Thank You up front for all help and assistance he gave me in helping me get the first one done.

So here we go.....

Step 1. Put some time aside and spend a few days visiting Greybeard - he has a much better workshop. Find a design you like - the original design -and then adapt it to modern materials. Scale it all up and build a form.

1.jpg (35.05 KiB) Viewed 5193 times

Step 2. Laminate up the bow.

2.jpg (46.11 KiB) Viewed 5193 times

Step 3. Laminate up some Siyahs.

3.jpg (31.26 KiB) Viewed 5190 times

Step 4. Attach Siyahs to bow.

4.jpg (23.44 KiB) Viewed 5184 times

Step 5. Spend several hours sanding everything to approximate shape.

5.jpg (32.1 KiB) Viewed 5184 times

Step 6. Spend several more hours thinning down the limbs to get it down to Godzilla weight so we can start tillering it.

6.jpg (39.67 KiB) Viewed 5183 times

Step 7. Make like the Incredible Hulk and get it to almost brace height. It is only pulling about 100lb here!

7.jpg (24.18 KiB) Viewed 5178 times

Step 8. Collapse with exhaustion when the Siyah attachment fails.

8.jpg (38.53 KiB) Viewed 5175 times

For those who are interested the failure upon examination showed that it was close to a perfect failure. All three components had been torn apart - the Fibreglass, the timber and the glue. I am of the opinion that the cause of the failure was that the Siyahs where not bound and my hand had moved out on them as the bow was put back on the tiller again. It was probably down to 90lb at brace height by this stage. Even if the whole thing had stayed together i was never going to be able to shoot it.

Step 9. Sit down, have a Coffee and plan what's next.

Step 10. Modify the form and the design and start it again.

The next version is already under way and the lam thickness has been slashed in half plus there is only 4" or reflex this time. And I have decided to lower the angle of the Siyahs and the Working limb section has gone from around 12" to around 18". Life can exciting sometimes.

The Further Adventures of Building a Manchu Bow will be see on this channel in a week or so.

[jcm]

Perhaps the 9 harmonies were not in balance?
Were the rites of Zhou followed?
I watch for more from the Bowyer of Jin.
Much good fortune
Regards
John

[perry]

Good on ya Grahame , character building when something goes south - great fun isn't it .

I was wondering , wouldn't it be a stronger conection if the siyah was fearthered out and sandwiched between the laminations , not the traditional method but you are not using horn and sinew either . It would still need some binding for insurance I think . I remember Grahame K making a long fibreglass composite type bow and he had limb stability issues from to much reflex . I also wonder if the length of the siyah's when using modern materials needs to be shorter .

A fibreglass composite type bow based on the long Chinese model is an intriging concept - keep the development work going , looking forward to Mach 2

For interests sake are you aware of http://www.attillasarchery.com/shop/ interesting to have a poke around .

regards Perry

[GrahameA]

Morning John

Things were in balance but someone was pushing the limits - and I mean pushing the limits. I will ask for guidance from the ancestors and see what they say.

Hi Perry

Good on ya Grahame , character building when something goes south - great fun isn't it .

Great fun - and we have learnt heaps.

I was wondering , wouldn't it be a stronger conection if the siyah was fearthered out and sandwiched between the laminations , not the traditional method but you are not using horn and sinew either . It would still need some binding for insurance I think .

Personally I am of the opinion that it there would be little difference. That method is what is used in the Toths. Yes, I did unwrap the leather on my Toth You definitely need a binding to stop peel failure starting. That both probably would not have failed in the limbs had been bound but it was still very much in the early stages of tillering and it was being pulled off the bow section and not the siyahs. It was probably my hand moving that did it in.

I remember Grahame K making a long fibreglass composite type bow and he had limb stability issues from to much reflex . I also wonder if the length of the siyah's when using modern materials needs to be shorter .

Hmm..., Stability - personal opinions is as long as the brace height is suitable it should not be a problem. I think you can get away with the long siyahs the real issue is the characteristics of the limb - and I don't know anywhere near enough. Narrow limbs are a definite - No, No -as they get narrower you lose stabilty in the limb and it can (and probably will) twist on launch.

A fibreglass composite type bow based on the long Chinese model is an intriging concept - keep the development work going , looking forward to Mach 2

Well the Mark II is under way and I will be taking lots more photos - well, actually I will not be taking that many as that task has bee handed over to Daryl who is really enjoying using my camera. It is the autofocus, etc.

I have looked at a fair few other on the web and they all seem to opt for low siyahs. And I have a sneaky feeling that is because they use Solid Glass limbs - which have very different characteristics.

My only concern at the moment is amount of water I have sweated out over the last few days sanding - it has been a few litres.

[jape]

Marvellous Grahame. I always thought you were a skinny chap with a frock coat and a flat hat ...
Remarkable to see the smile on your face after the collapse, you have true grit sir.

[Graeme K]

Hi Grahame
One of the problems with the adaption of traditional designs to modern materials is -- as you have found, that you end up having to reduce the thickness to get usable draw weights and this reduction leads to torsional instability.
So the message here is that you can not use the unstrung profiles of traditional bows and just make them using modern materials -- you have to compromise the design to look like a traditional bow when strung and use your understanding of the modern materials to get that to work.
I know this is not much direct help but without seeing the thing you are working on in real life I can not guess how best to advise you.
The other thing about your siyah failure-- although you see people just gluing them on the surface and sometimes getting away with it, this is the worst possible approach. The reason is that it loads the glue in such a way as to produce high " peel " loads and this is the greatest weakness of modern glues ( and probably all glues). You often find that you can provoke a failure like you have where it has torn the material in the joint and the substrates apart at less than a tenth of the load that the glue will allow in any other form of loading.
The suggestion that Perry made about putting the siyah between the glass lams is the easiest fix and generally works fine as long as you make it nice and long and tapered to give plenty of transition from the bending zone to the non bending siyah.

Hope this helps -- It is great to see you trying something new and interesting and i have no doubt that it will work with a little finessing.

Graeme

[GrahameA]

Hi Graeme

... it loads the glue in such a way as to produce high " peel " loads and this is the greatest weakness of modern glues ( and probably all glues).

You definitely need a binding to stop peel failure starting.

I have learnt that one. I was considering bopping down to Bote Cote Pacific and getting filler and on the next one building up a fillet either side of the siyah in an epoxy/filler mix. I have have a lot of success with such joints in the past.

Yes the narrow limb is an issue and the next will be significantly wider and thinner. So much to learn, so little time.

Hi Jape

Would you prefer me to wear Academic dress?

[jape]

Hi Jape
Would you prefer me to wear Academic dress?

No thanks mate, blokes in any kind of dresses freak me, maybe a cheongsam though?

[perry]

There is double the glue surface if the siyah is sandwiched between laminations and you could add thin laminations or horn or timber on the back and belly side of the siyah that would further reinforce shear forces on the siyah's , weight at the end of the limbs would not be any bigger issue as the siyahs could be thinned proportionly . Graeme K's suggestion of a longer feather would increase the glue area substancially . I think this in conjuction with a compromise in siyah length would make for a torsionly stronger limb than a bound long siyah could produce in a fibreglass/ timber laminated bow . I have also found that long fadeouts on the riser are the go for tortional stability on thin limbed bows .

Dig , Dig , stir , stir - use carbon laminations and cores to further increase torsional stability , perhaps this would allow greater reflex in the form so those string nocks could touch in unbraced profile [ forgive me ]

regards Perry

[Gringa Bows]

very interesting Grahame,you obviousely have more patience than i do looking forward to the next one.........Rod

[Graeme K]

I'm wIth Perry -- Foam cores with diagonal carbon and siyahs that are tubular and hollow made out of woven carbon sleeve with a bias weave so you can get it neck down tightly on your wax form that you will melt out after it cures.

Graeme

[longbowinfected]

Thanks GA.
I love watching others build character.
People with big tidy workshops are suss.
Why does the word dress pop up so much.......ever since TEX arrived I think.
I now remember why I do not make bows....no need, Steve lives a couple of suburbs away and his worst effort would eclipse my best. I truly dips me lid in awe.
I love making arras because they never break until I get at least one use and with care they can be recycled/repaired.

Kevin

[Graeme K]

Hey Kevin -- That is the worst excuse I have ever heard for not making a bow -- Its not how good it turns out but the fact that you gave it a go. The test of success is whether the arrow moves forward not much else and the only bows that break before you get to use them are the ones built by people who have not thought it through or taken advantage of all the information and help available on these sites and from the people they know who have experience. Stop making excuses and give it a go!!!!!!
The only guarantee of failure is failing to try.

Graeme

[NCArcher]

Quick question Grahame, where was the tillering string attached when it failed?
Great effort by the way. Thanks for the WIP. Keep 'em coming.

[longbowinfected]

GK
you are right.
The real problem is kicking everyone else out of my garage and all the crap left behind by my first three children when they flew the nest, just to get close to my crap so I can tidy up. If that ever happens without someone saying "hey Dad has made some room.....let's take some stuff back home for storage"
I have only been shooting longbow for a couple of years, I would not like to rush things.
I like making my own strings, arrows, leather wear because I can do them in the lounge room where it is warm [not that we have any heating].

Seriously GK I get extreme hay fever and other reactions to green things and the dust off things that used to be green. I am also very much affected by glues and other materials. This is even if I wear full PPE. This was the reason why I moved to the Blue Mountains. Just ask Steve how badly even something like pollen or unscented talc in small quantities does to me. On the bright or plus side, my sense of smell is so acute that I can walk into a building and detect minute amounts of fungi typically associated with termite attack and know that termites are there to be found within 30 seconds if the building has not been actively ventilated.

I will get to that stick one day that you gave me....I promise.

Kevin

[Mick Smith]

I'm looking forward to seeing the mark 2 version Grahame. I'd also be inclined to build the siyahs in a way where they're sandwiched between the fiberglass limb laminations, in much the same manner as the Grozer's that I've seen. Not only does it look great, it would have to be extremely strong.

I'm sure that success is just around the corner.

Mick

[GrahameA]

Afternoon All

I'm sure that success is just around the corner.

Mick

I already have had success. You would not believe how much I have learnt doing it. The only trouble is getting the time.

And today has been wonderful. Went to the club, made some strings for the club bows and shot my new acquisition - a Nishizawa. Mmmmmmmmm............

Perry/Graeme

use carbon laminations and cores to further increase torsional stability , perhaps this would allow greater reflex in the form so those string nocks could touch in unbraced profile

Don't worry, the thoughts have well and truly crossed my mind. Although I was thinking of more of a foam core and just leaving it there.

Is this the gauntlet being thrown in to see who is the first to build foam cored carbon laminated limbs. Very Trad I say.

[Graeme K]

I was thinking " Uber Trad " might be the appropriate term. And YES.

Graeme

[perry]

What is Tradition Grahame ? , but passing on accumulated knowledge/advances to the next generation

I'll bite with uber - Ober-trad [ higher or supererior ]

regards Perry

[Graeme K]

One would have to make ones own decision about that old chap

GKL

[GrahameA]

Morning NC

Quick question Grahame, where was the tillering string attached when it failed?
Great effort by the way. Thanks for the WIP. Keep 'em coming.

As per the photo. However the bow was bent a bit more and I was hauling down on the ends of limbs with my hands.

closeup.jpg (17.18 KiB) Viewed 4854 times

Nishizawas are even better than one can imagine.

Morning Perry/Graeme

What is Tradition Grahame ? , but passing on accumulated knowledge/advances to the next generation. I'll bite with uber - Ober-trad [ higher or supererior ] regards Perry

Uber-Trad it shall be. (Remember, I already have had my knuckles wrapped for suggesting that the next generation will see the early compounds as Traditional Bows.)

[NCArcher]

As per the photo. However the bow was bent a bit more and I was hauling down on the ends of limbs with my hands.

Ah now I see. Lucky you didn't head butt the tillering stick when it let go.

[pommy chris]

what timbers have you used?

[GrahameA]

Hi Chris

what timbers have you used?

Hickory Lams, Cherry Siyahs.

[greybeard]

GrahameA sent a link to me relating to a Manchu bow circa 1800’s.

As I love a challenge I intimated to Grahame that he/we should have a go and that my workshop was available. Although the bow had extreme reflex I felt that we were up to the challenge.

Is it possible to replicate a bow by replacing sinew, bamboo and horn with fibreglass, hickory and epoxy resin and get it to work? Maybe carefully selected natural materials are more homogeneous than mixing synthetic with natural materials? [In this instance please disregard modern recurves and laminated American style flat bows.]

When the ‘experiment’ finally made its way to the tiller board the limbs were reluctant to bend. As evident in the photo the tiller string was clamped just in front of the siyahs as they had not been reinforced with bindings. This point was almost halfway from the handle fadeouts to the tip of the siyahs. Not having the advantage of the leverage factor it would be difficult to work out how overbuilt the bow may have been.
The above scenario would be similar to having a 68” bow say at 50# on the tiller board and having the tiller string placed mid limb. When pulled down the poundage increase would be enormous.

Never a dull moment, Mark II is on the way.

Daryl.

[rapsod]

Where did you brought fiberglass?

[longbow steve]

Hi Grahame, A good experiment and thanks for sharing.
I recently looked at some horse bows made by respected European Bowyers and the Siyahs were bound no doubt for added strength but they also had side plates glued on possibly to add more integrity to the Siyah.
If you didnt want to splice the Siyah (due to the alignment concerns)could you extend the central laminations beyond the glass and glue to these then add side plates to reinforce the area then bind? Works in my mind, hope I explained well enough Steve

[longbowinfected]

These side pieces and such are used in Yumi bows I think. They look suspiciously squared up.

Kevin

[jape]

For interests sake are you aware of http://www.attillasarchery.com/shop/ interesting to have a poke around .
regards Perry

Just one 'l' in attilas Perry!
http://www.attilasarchery.com/shop/

[GrahameA]

Where did you brought fiberglass?

http://www.binghamprojects.com