Yumi with Greybeard Sensei (Pic Heavy)

[GrahameA]

Afternoon All

Some time ago I started a list of bows I wanted to build. On that list was a Yumi albeit a fair way down the list.

Then the other week I stumbled across an interesting print on ATARN. This was the print and what intrigued me was the shape of the bows that were being shot and that they were almost symmetrical.

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Anyhow one thing led to another and I ended up doing a lot of reading about Japanese Yumis and how they were made. Plus Daryl, aka Greybeard, had some Bamboo and he has a fair bit of experience working with Bamboo.

So that was it over a cup of Coffee the decision was made to have a go at a Yumi - and a Bamboo one at that.

So here we go.

Step 1.

Get a piece of bamboo and cut the back and belly laminations. Then sand off the backs of nodes.

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Then using a sharp spokeshave - and when I say sharp I mean sharp - set to a fine cut cut down the back of your lamination until it is all smooth and around 1/8" thick - ignore the thickening at the nodes.

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Then make another to match the one you just made - that will give you one for the back and one for the belly.

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Note: that because the Yumi has a timber wedge at the nocks and only the back lamination appears to run the full length you will need to cut the belly lamination shorter.

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And then you get to spokshave down that lamination - with your razor sharp spokeshave set real fine.

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Those pencllied areas are high points which have to brought down.

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\

Note those shavings are paper thin. If they are not you run the risk of damaging the lamination.

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And as with all such things you get to sand the laminations to remove the hills an hollows and it helps you to appreciate the cooler days of winter.

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Continued on next post.

[GrahameA]

So more on the Yumi.

So now you can clamp your back and belly laminations together and make them the same.

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Using your trusty razor sharp spokeshave.

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Okay time for some core material. Grab a Bamboo floorbaord and cut in half. Then grind off the finish.

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Then feed it through the bandsaw to make some lam' blanks.

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And try it in the form. That is a Torges adjustable form.

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And play around with it till you get the shape you want.

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Then glue all the core lam's together. Note that I have had to splice one of the lam's to get the length.

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Three laminations, some glue and a few clamps later. That can sit overnight for the glue to go off.

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Next day - "Hey Presto". The core of a Yumi.

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Get all the glue dags off.

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Continued on next post.

[GrahameA]

Trying the wedges for size, shape and fit.

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Out with the spokeshave and form the end wedges.

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And glue the wedges on - then you get to wait until tomorrow.

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Next day glue on the back lamination.

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And a day later sand the core to match the back lamination.

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And then glue on the other lam.

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The whole bow was pretty sloppy at this stage and I was a little concerned that it might be a bit light. However Greybeard Sensie suggested that the addition of the last lam would stiffen it a bit. (This will be know forever as the understatement of the Century.)

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Next day - clean up the dags and then spokeshave off the edges till the bow is all cleaned up and tapers nicely.

Hmm..... Greybeard Sensei was right about that last lam stiffening things up. Let me put it terms everyone will undertand - even Arnold Schwarzenger was not go to use this bow.

So here i am sawing the bow down the middle Lamination.

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Continued in next post.

[GrahameA]

After sawing the bow down the middle Lamination one gets to shokeshave it back to a glue line on each piece.

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You can see the colour change as you come to the glue line. It is just like following a growth ring on a self bow.

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Several hours and a lot of sweat later you glue the two halves together and head off for a cool shower. Humour is not high at this point.

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Next day. Challenge 1 is to string it and get it on the tiller board. (And it is somewhat lighter than yesterday.)

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Greybeard Sensei.

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Making a really long string.

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"Shazammm"

An asymmetrical bow. And I can draw it.

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Well it shoots. Next job is put some bindings on the wedges and then shoot a few arrows through it to see if it wants to change. Then on go the fancy bindings.

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So if you are feeling bored and have a bit of spare time - a project.

And. "Thanks, Daryl". Another series of lessons learnt from the Sensei.

[maurizio]

wow!!! what an odyssey!! graet job!!!

[longbowinfected]

one of the guys at Liverpool shoots 36 inch arrows in the bow with is Yumi.....full length flights.
I think the Yumi looks better shot your way.......what was it like? smooth? fast?

Great work sensei and grasshopper.

Kevin

[jcm]

Arigato gozaimaso.
Deshi and Sensei
Regards
John

[shikari]

Excellent job,I think you might find this very interesting.http://paleoplanet69529.yuku.com/topic/22774
Regards
P.J.

[ichiban]

sugoio, kore wa boku no ichiban ga suki desu! any way nice one how much reflex is in there?? have you determined they type of yumi it is? ihave a book about the yumis and its a good read but it focuses more on kyudo as a sport and its traditions

[GrahameA]

Good Morning All

wow!!! what an odyssey!! graet job!!!

Odyssey - yes, that is apt description. However, I did learn a lot.

one of the guys at Liverpool shoots 36 inch arrows in the bow with is Yumi.....full length flights.
I think the Yumi looks better shot your way.......what was it like? smooth? fast?

I need to make arrows for it. Only having shot a few short arrows through it I am at a loss to describe it. I would say it shoots like a Bamboo backed bow. With longer arrows I expect it to be fast.

Arigato gozaimaso.

Thanks John. Deshi is an apt description. Only a few more years of learning to go.

Congratulations on the bow and fantastic post, I found that really interesting!

Thanks Tony - I am glad you enjoyed and I hope I have inspired you to, "have a go"

Excellent job,I think you might find this very interesting.http://paleoplanet69529.yuku.com/topic/22774

Read the post - not quite ready for doing one that way.

any way nice one how much reflex is in there?? have you determined they type of yumi it is?

It started with about 12" but it has dropped a lot. Probably about 4" now.

As to the type of Yumi - Well an old style and I will leave it at that. Do not know anywhere near enough about them. But I do want to build another. This is not a Kyudo bow - much to heavy for your average Kyudo shooter.

Have a look at the woodcut on this page.
http://www.tokumeikan.com/equipment.htm

~~~~~

Intentions are to shoot this one a bit and get it sorted out - it is a whole new world for me. Then I may be in a better position to make some comments about it.

The limb length ratio is 39 to 51. Modern Yumis are 33 to 66

[Glenn]

Good job Grahame, looks as though that would have been an interesting project. Good to see you had an old hand looking over your sholder now and then having tea and biscuits......Glenn......

[Gringa Bows]

good job Grahame,and it could double as a surf rod ...............Rod

[longbow steve]

Looks like a fun project Grahame, a shame you had to cut it down the middle to get the weight down.
I have just prepped some strips of bamboo for a bamboo back and belly bow to preceed my Yumi attempt . Steve

[greybeard]

What a learning curve.

Although I have made several longbows incorporating bamboo for the back and belly laminations it was a new ball game when guesstimating core thickness as well as back and belly laminations for such a long bow.

Bamboo is full of surprises when used for the outer laminations. I am confident that Grahame will back me up on this statement.

Obtaining the desired draw weight can be difficult as I have found that bamboo back and belly longbows [depending on core material] can lose up to 10# when shot in.

This exercise has taught me that when trying to make an asymmetrical bow around eighty inches in length you need to throw western thinking out the window.

The final product may not quite resemble what we may have envisaged in our minds but at least Grahame has a shootable bow.

In essence if we do not experiment we will not learn.

I give due credit to the aspiring bowyers on this site who are willing to think outside the square and have a go.

Daryl.

ps. Spot gets nervous when Grahame braces a bow.

[GrahameA]

Good Morning Steve

Looks like a fun project Grahame, a shame you had to cut it down the middle to get the weight down.

"Yes" and "No". If I had not done it I would never have been able to shoot the bow and in the processing of doing so I learnt how to do it and had the pleasure of spokeshaving it back. That teaches you patience and tolerance. Plus I learnt a bit about Bamboo back and belly bows.

I have just prepped some strips of bamboo for a bamboo back and belly bow to preceed my Yumi attempt . Steve

Go for it. I am excited you are having a go. According to kevin there is someone down there who has one - go and have a look at it and get a pattern off the shape and check out if the bow is stiffened around the handle area or into the first section of limb.

Good Morning Daryl

Bamboo is full of surprises when used for the outer laminations. I am confident that Grahame will back me up on this statement.

Yep! It is full of big surprises.

The final product may not quite resemble what we may have envisaged in our minds but at least Grahame has a shootable bow.

And it looks like the bows in this wood cut. I can relate to the issues he is having stringing it.

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In essence if we do not experiment we will not learn.

I give due credit to the aspiring bowyers on this site who are willing to think outside the square and have a go.

Very much so. I support that Philosphy and those comments wholeheartedly.

And the bow meets the pre-1900 ruling as an unexpected side benefit.

[Brumbies Country]

Great bow build pictures and description Grahame and thanks for sharing it with us. Certainly does meet the pre-1900 Historical bow criteria

Simon

[Stickbow Hunter]

You have been keeping yourself busy Grahame. Congrats on getting a shooting bow. Oh, I much prefer to only have to make a bow once.

Jeff

[GrahameA]

Good Morning Jeff

I showed it to some acquaintances last Tuesday evening and was lucky enough to get it back. Took it to the range last Saturday and shot a stack of arrows through it (around 100). Since new it has lost a lot of recurve but seems to have reached the stage where it has stopped losing it. Reading a bit more about them it would appear that the set issue is common with those made in Japan. Even so I am still happy with it.

It now has the bindings on it and so looks a bit more like the ones you see during Yabusame. I am shooting it from the left side using a mediterranean release and take the draw all the way back to end of my ear. The extreme extended draw that you see in Kyudo is not the omly length of draw. The shorter draw to the ear seem to be more common with the bow when it was used in a in military application. i.e. The Japanese where just the same as many other people and drew the bow to the ear. Although I did come across one reference which talked about about a high anchor and a low anchor. The low anchor (to what appears to be the neck) was used by archers when they where wearing helmets..

Anyhow the bow shoots well - the archer not as well. And interetsingly the long power stroke does accerate the arrow well and it does shoot quiet - surprisingly quiet. I definitely want to build another (once only next time) and with a higher poundage.

[Stephen Georgiou]

Very impressive Graham!
You have definitely inspired me to have a go at building a bow.

I need to get a band saw and a drum sander. Any brand suggestions? Size, horsepower etc?

Any advice would be greatly appreciated.
Regards Stephen.

[GrahameA]

Good Morning Stephen

I need to get a band saw and a drum sander. Any brand suggestions? Size, horsepower etc?

That grinder I am using is Greybeards Lam grinder. Speak to him regarding equipment details.

Bandsaws - aaggghhhh......................

If you want to cut lams you need something that will cut straight - Daryl will have details on his. Wide-ish blade will not go astray, Thick blades is timber being thrown away. So it is a bit of a balancing act.

I have a small timber bandsaw. It is great for cutting footings etc. Not so great for doing lams. If I was to be cutting Lams I would find somewhere I could access one.
eg http://www.woodnyou.com/

Or why not just by the lams pre-done. If you are only going to make a couple of bows (say less tha 10) it is probably cheaper to just buy kits of what you want from John Clark at Ausbow. Just give him a ring and specify what you want the final bow to be like and he will send you all the pieces - and buy his book. You can build a longbow on a piece of RHS or a piece of 4X2.
http://ausbow.com.au/ausbow.html

Simlarly you can get kits from Binghams
http://www.binghamprojects.com/

Hope that helps.

[NCArcher]

It now has the bindings on it and so looks a bit more like the ones you see during Yabusame.

I don't believe you Grahame. If there are no pictures it didn't happen

[Stephen Georgiou]

Thanks for your advice Graham.
I am planning to build a few bows as i have a ideas about shape and materials that I would like to experiment with. I'm sure I will make plenty of mistakes along the way but what the heck!
Cheers SG

[GrahameA]

Good Morning Tony

It now has the bindings on it and so looks a bit more like the ones you see during Yabusame.

I don't believe you Grahame. If there are no pictures it didn't happen

Picture. And does'nt it look good.

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[Stickbow Hunter]

It looks good (the bow that is) mate. One thing I notice it is missing and I don't think you mention the reason anywhere, why no recurve at the limb tips?

Jeff

[GrahameA]

Hi Jeff

Because the builder, klutz that he is, did not put enough in and the main wood cut I was working off did not show it. I added some unlike the original woodcut but most of it has come out now there is however still a little when the bow is unstrung. Next time I will build in a lot more.

[Stickbow Hunter]

Thanks for the explanation. It still looks good and is a great achievemnt.

Jeff

[Outbackdad]

Graham

Found this place to go to when Lewis and I are in Tokyo in April.

http://www.asahi-archery.co.jp/asahi/asahimap.html

May have to bring something home.

Eddie

[GrahameA]

Morning All.

I received a couple of photos of the Yumi in action at a Festival over Easter and they show it in its finished state. So here it is being used to an target round. I obviously need to make some more arrows for it.

[perry]

What an Endeavor Grahame, top effort. Kudos to Greybeard as well.

Bamboo lam Penobscot next, please.

regards Jacko

[Gringa Bows]

Man thats a lonnnggg bow,looks good Grahame..................Rod