Manchurian (Chinese) Repeating Crossbow

[Dane]

Hi, all. This is only one photo a friend took at last week's NEPSG in Woodbury. This is a little Chu Ko Nu, the Chinese repeating crossbow. I do plan to do a detailed buildalong of one of these, and probably write an article for PA, since everyone who plays with this have such fun. I let everyone who wanted to try it, and at least three other guys wanted info to build their own. It is a very simple project, and I build this one from scrap wood, with the only metal being two brass rods and four brass washers.

They go back to perhaps 250 BC or earlier. A peasant's weapon, the have a box magazine and 10 fletchless, gravity fed bolts. They were normally tipped with poison, as they are very weak. However, I have seen a painting of very large ones being used during naval battles, and they were used during the Boxer Rebellion, 1898 - 1901.

Feel free to ask questions. The symbol I had painted on the magazine is a symbol for rain, the poetic idea being it puts for a rain of arrows. And they shoot fast, about 1 bolt a second.

Thanks for looking,
Dane

[Dane]

Well, if memory is not messing with me, I posted these in progress shots on a crossbow community, but not here. Maybe you guys would enjoy seeing this little weapon as I created it. This is not a detailed buildalong, but more a photo essay kind of thing. An article will have all the grungy details on how and why

First, I should say that the Chinese jacket you see me wearing is a bit of the inspiration for this...dumb, but true. I bought it in New York's Chinatown, and this is one instance where you actually want a product to me "made in China." Second, I just got myself a new wok, and have been doing a lot of cooking with it, so that is another reason this build came to mind. It has been about a year ago I built this little guy.

If you don't sense I am totally nuts, here are some pictures, from beginning to end, with a few explainatory notes. Enjoy.



That is the box magazine parts. An actual Chinese builder would have used one solid piece of wood, chiseled or sawed out to make the cavity for the bolts. That would have been way no fun, so I cheated on this here. Mostly, the weapon is an exact replica of one that dates to late 19th century. I also used Tightbond III instead of hide or fish glue.

The magazine, stock, and lower magazine with the antler trigger. It makes sense later.

This is the front block of the magazine, and will become also the barrel. 

This is the trigger and string slot along with the trigger. The trigger is bit of antler, t-shaped. It rides freely in the slot, and when you bring down the magazine via the handle, the trigger is pushed up, therefore pushing up the bow string held in place by the slot.

The magazine glued up and ready to be sanded.

Another detail of how the T-shaped trigger works.

[Dane]

 Here is a good shot of the T-shaped...trigger. You can get an idea of the size of it. I made it from a bit of leftover horn, cow I think, but any will do. I used the front part of the horn, which was solid.

This is the front top part of the stock, aka the tiller. Notice a rounded slot I am fashioning into it. The bottom of the magazine assembly is also rounded, and the mechanism slides along this as you cock and fire the crossbow.

Looking prettier here.

This series of pics shows me making the bow mortise. I used a drill to drill out some waste wood, then chisels to clean it all up and sandpaper to get it nice and pretty.

[Dane]

Next, I made the cocking handle. I used mortise and tenon construction, and it is not hard at all to do.

First, i fashioned the belly rest. I call it that, as I am not sure what they called it back in ancient China. When you shoot this bow, you brace it against your stomach or chest, or maybe a theigh or other hand body part. You hold the stock with one hand, and manipulate the cocking handle forward and back with the other.





Next is the cocking handle.






Now, fitting it to the stock.

[Dane]

The last photo shows it being either pushed foreward or the opposite. I had to drill three holes, on in the stock and two in the two cocking handle pieces. I used brass threaded rod for the rivets, and four brass washers. Making the rivets was really easy, just placed the rod into the vise, peened down one end, cut the rod to length leaving just a tiny bit, about 1/8" past the second washer, and peened it down carefully so I didnt wack and mess up my wood. It really isnt hard to do, and just takes a bit of practice.

Clearning up the string slot. You can hopefully see, along with the photos of the magazine, that this slot is for the string. Make sure it is nice and smooth, with smoothed edges so they don't cause an early demise of your string.

This ugly little shot is an ugly mockup of the bow itself, just to make sure I got my geomerty and dimension right. The bow itself is two pieces o bamboo, planed and sanded down, and nested on on top of the other. No glueing for this, as they need to ride against each other as you cock and fire the bow. I made a jib and steamed the pieces to get it close to the shape I wanted. Yeah, no reflex here

[Dane]

Finally, shots of the bow being made.







It may be hard to see here, but the bow is held in place with a wooden wedge, tapped into place. Really simple contruction, and following exactly the dimensions of the original bow I was replicating.

And yes, you drill two holes through the ends of the bow to string it up. It works fine for a low powered bow, and hasnt failed yet.

Now, steaming the bow into shape. Since the kitchen is my kingdom and the Caliphone is all mine, i dont get chased out by an irate wife. And, gaze upon Davenport, the love of my life. She loves having her picture taken.

[PEARL DRUMS]

You have all the fun Dane! You get after some of the coolest projects I swear. Nice work.

[Dane]

And here I am, ready to defend the wall against evil hordes of barbarians. I haven't yet painted on the rain symbol





And at last, a grouping at about 25 feet. This was my first day shooting it, and I was getting good groups. These things lose accuracy fast, but they were close in combat weapons, and the poison speaks louder than hunting stories

I hope you enjoyed this. Ask questions, please.

[Dane]

You have all the fun Dane! You get after some of the coolest projects I swear. Nice work.

Thanks, man. You make your fun. You know that. Your bows blow me away, and you have far more bow making skills than I will ever have. But I have found my little niche. The last pics I posted while you wrote this.

Dane

[Dane]

One clarification. I kept saying antler for the trigger, but it is actually cow horn. Antler would work fine, though.

[Del the cat]

Nice buildalong.
Not sure why the huge deflex in the bow, it must be robbing a huge amount of power.
Del

[Dane]

Because the original artifact had set that much, from what i could tell. Maybe it originally had no set, or it was even reflexed a bit, but I played it really safe for this first bow. The author of the paper I read said his bow had a rawhide string. I didnt want to mess about too much and possible break the bamboo bow this time out, but a pre-wetted rawhide string will dry and tighten. Sure, it is a whimpy little guy right now, but i do plan to build more of these and experiment with bow woods, string material, and so on. And a nice thing about this one is I can easily nock out the bow wedge and mess about easily enough. And the painting of the repeater used in a sea battle must have been really powerful, as it is much later than this, at least twice as large. You also get a 4/1 mechanical advantage with the lever, and I am guessing long levers will give you more advantage.

[Dane]

Del, I should state for the record I am about to get my power fix. I've been commissioned to build a 900 lb. German crossbow, spanned with a cranquin. Right now I am building a 200 lb. German crossbow in oak to perfect a double axle trigger, since I feel with that much power, it would be wise to do a bit more complex a trigger mechanism. I was just making antler rolling nut bearing blocks. Wish me luck . Once that is underway, I will post info and photos here.

Dane

[coaster500]

Very cool!!

Maybe a video clip of it in action???

[Del the cat]

Del, I should state for the record I am about to get my power fix. I've been commissioned to build a 900 lb. German crossbow, spanned with a cranquin. Right now I am building a 200 lb. German crossbow in oak to perfect a double axle trigger, since I feel with that much power, it would be wise to do a bit more complex a trigger mechanism. I was just making antler rolling nut bearing blocks. Wish me luck . Once that is underway, I will post info and photos here.

Dane

Good luck indeed, can't wait for the build along of that bad boy!
Del