This is a tutorial on how to make bamboo target arrows. I'll start with fresh bamboo, ending with straight shafts, ready for putting on the point, nock and feathers.
For arrows, just about any bamboo can be used as long as it has the right diameter. You can buy dried bamboo in most gardening centres (meant as sticks to guide your plants). Better and cheaper is to find your own place where you can cut fresh, green bamboo stalks. A preferred and proven bamboo species is Pseudosasa japonica also known as (Japanese) arrow bamboo. It has a nature of being straight, without sidebranches, and to have a uniform thickness. In this tutorial, I'll be using Pseudosasa japonica I cut myself.
How to recognize this bamboo? Please take a close look at these two pictures. They will show you the habitus (morphology) of the plant.
Harvesting green stalks
Bamboo stalks are hollow on the inside. This means they can crack lengthwise when cutting them with a pruning shears. However, fresh stalks don't split nearly as easily as dry stalks do. To prevent splitting, you can cut them through the nodes. Myself, I just use a pruning shears to harvest my stalks.
Things to pay attention for in the field, when harvesting your stalks:
- Bamboo leaves are sharp! When walking through thick bamboo bushes, you'll get covered in small cuts on your limbs (arms and hands mostly). Besides this, there are also small hairs on the leaves, which make your skin itch.
- Be selective in the field. This involves:
1) Harvest only stalks which are long enough (and not too long either). After all, you need about 32" minimum. I don't bring a measuring tape myself, but just eyeball for 35 to 40". I found out you can only get one shaft per stalk.
2) Select for the right thickness. Anything under 7 millimeters at the butt end is useless. Anything over 11 millimeters at the butt end in useless too. After all, you can't grind bamboo back the right thickness as you can with wood. You will see that the shorter the entire stalk is, the more difference there is in thickness between the two ends: the longer the stalk the better, because of little taper.
3) Select for age. In one year, one entire stalk is formed, sometimes up to 10 feet high. However, these one year old stalks are very soft and pliable. There has not yet been much lignification. Avoid one year old stalks if possible. This can be hard when they are growing in the field, but once the stalks are dry, you will see a difference between these and older stalks. On the other side, stalks can also be too old. After multiple years, the shafts will loose their bracts, which are recognized by their brown color. The stalks become very woody, and are very stiff and heavy; too much for my liking.
Try to harvest MANY stalks; you will need to sort, spine and match them later. I don't think the harvesting season matters. Bamboo is green all year round, so will contain water all year round.
Preparation for drying
Bring the shafts home. This works easier from now on
First thing to do, is to remove the bracts from the green stalks. This can be done very easily by grabbing the stalk firmly in one hand. Grab a bract at its base, and twist the stalk with your hand. The bract is easily shed.
Left: green stalks I just harvested. Mid: green stalks. Right: bracts as they've been removed from the green stalks.
This is a close-up of the ends of some stalks. I put in a AA battery for camparison of thicknesses.
Next, we can cut them to length. Or at least: approximately to length, which is 32" in my case. This step must be done with care. You will now have to cut between two nodes: the internode (this is the section of a stem between two nodes). This is fragile, and will most likely crack (some) stalks, even if done green, when done with a pruning shears. Best is to use a saw with fine teeth (hacksaw for example). Before you cut the stalks to length, select the best 32" possible. Shift your shaft in the stalk until you'll not get a node right at an end, or until the thinkness ot the ends is as desired.
The third thing we can do, is enhance drying speed by perforating the chambers in the stalks. However, this is not necessary, but will reduce drying time. At the moment, the nodes seal chambers within the bamboo. If you drive a metal rod (wire) through the nodes, air can circulate through them. To do this, take a straight, stiff metal wire of about 2 feet. Hammer one end flat and file a sharp tip to it. Put the wire in an electric (wireless) drill. Push the wire through the bamboo.
This will shorten drying time with about 50%.
Drying the stalks
Bundle the stalks to keep them a bit more straight, and for ease. Place them in a dry room. Depending on the climate, drying will take about 2 to 3 weeks if perforated, or 4 to 5 if not perforated. When you dry the stalks indoors, away from direct sunlight, they will remain a bit greenish.
If you live in a sunny region with not too much rain, you can dry them outdoors, in direct sunlight. This will decrease drying time, but sunlight also changes the color to more brown and less green.
When the stalks are dry, you can prepare them for heat straightening. One thing you need to do, is to clean the shafts. Remove everything but the shaft itself. So wipe off sand and dirt, and more importantly, remove the bud and the left overs from the bracts.
Before cleaning, the node will look like this:
Use a small knife to cut off the pieces of bract. You will end up with something like this:
You need to remove these bits because they'll catch fire later on. Nothing to worry about, but it smells, turns black, and adds mass to the shaft withough adding strength.
Heat straightening the shafts
I use my gas stove to heat the shafts. You could basically use any type heatsource, although I would recommend a type you can aim at one specific point. Heating the entire shaft over a campfire is not good: you will bend every section when applying pressure, also the section which are straight. I've read on another website a candle is a good heatsource. However, I could imagine this works rather slowly, and might place soot on the shaft. A gas burner, windproof lighter or bunsenburner will work just fine I guess.
Make room around your gas stove. The 32" long shaft needs to be manouvered in the flames, so it needs some room.
My gas stove turned on medium, with one shaft I'm straightening. Note the brown section I just heated.
Look at your shaft carefully from both ends. You will see bends at both the nodes, and the internodes. Usually, the nodes will have more wiggles which are also more difficult to remove. In contrast to another website, I highly recommend you to straighten the internodes first, and then the nodes. When straightening the nodes, you need to know what the straight line is you are following to make the shaft straight. This straight line is basically the collection of internodes. I hope that makes sense.
Unstraightened shaft. Note bends at the internodes, but more severe bends at the nodes.
Start with one internode. Look from one end of the shaft over the length of it, while turning it around multiple times. Heat the bent section(s) until they turn light brown. Keep rotating the shaft, and move it from left to right too! Don't hold the flame on one spot too long: black shafts are no good. Usually, I only heat about 1½" to 2" of shaft at a time. It takes only ten to twenty second to heat the shaft sufficiently. The shaft remains pliable for about ten to fifteen second, although minor adjustments to the shaft are easily done after twenty seconds.
Right after heating it, you can bend the shaft with your fingers. You can really feel it has become pliable. Work fairly fast now, checking for straightness often.
Internodes straightened, nodes have yet to be done.
It works easiest if only one part of the shaft is heated at a time. This allows you to handle and hold the shaft easily, while straightening that one section. As long as a section is too hold to touch, you can bend it (and burn your hands ). When a section is straight, you can cool it down using a wet sponge or towel. When cooling, it will not jump back into its bent form. Instead, once cool, it will hold its shape very well.
Keep a wet sponge at hand to cool down straightened sections.
When the internodes are straight, you can do the nodes. You will see very distinct and sharp bends at the nodes. The shaft looks like a lightning bolt, I think. By now, you know how much you need to bend the nodes. Doing the nodes is basically the same process, although the nodes will resist bending a bit more. You need to "overbend" more. A bit of experience (such as two snapped shafts ) will tell you just how far you can go.
Straightening one shaft will take me about ten minutes.
Hey! We got some straight shafts now!
That's what I call straight!
A close-up of straightened shafts (bottom) and unstraightened ones (top).
More straight (left) and unstraightened (right).
Next, you need to cut the shafts to length. This depends on your drawlength and preferences of course. Myself, with my 29" drawlength,
I cut my shafts at 30½" I select the best 30½" for that, avoiding a node at the last two inches of a shaft.
The shafts are now still hollow on the inside. This makes them weak at the tips: they will split quite easily when applying pressure. The cavity makes it more difficult to attach the nock especially, but also the tip. Best thing is to insert a dowel into the shaft and glue it into place. This will give you a solid tip, making it stronger and easier to attach the tip and arrownock.
In order to insert a (wooden or bamboo) dowel, you need to create a uniform inside of the shaft. This can be done with a drill. I found out that either 5 millimeters or 6 millimeters will be effective for almost all shafts. Drill holes in both ends: try 5 mm. first. If this slides in too easily, you need to switch to 6 mm. Drilling ALL shafts with a 6 mm. drill bit will cause the thinner shafts (spined maybe 30# to 40#) to have a very thin wall.
Caution: when drilling, your drill bit can suddenly "grab" the bamboo, and pull itself in rapidly. This very easily splits the shaft. If you want to be sure not to split a shaft, wrap some scotch tape around the end tightly.
Using a cordless drill with a 5 or 6 mm. drill bit to create a uniform hole in the last 1½ to 2" of the shafts.
Next, we can fill the hole. Some holes will be 5 mm. some will be 6 mm. So you also need a plug to fill it with. Myself, I use bamboo plant stakes for that. They come in different diameters. I had plenty laying around, most between 4 and 7 millimeter. Select different sizes (both 5 and 6 mm). You can make a setup like mine, to cut off plenty of plugs, all having the same length. I use about 1¼" or 1½" of bamboo for the plug. Sand a slight bevel to each plug end, to insert it into the shaft easily. Do some test fitting to see if the plug fits easily and doesn't jam, but also make sure it doesn't slide in too easily.
Creating a batch of plugs from bamboo garden stakes.
We can then glue the plugs into place, using some polyurethane glue for instance. This glue foams, closing gaps this way. It is also a very strong glue.
Squeeze some glue into the shafts, and spread it around with a thin stick, to cover the inside of the bamboo shaft. Squeeze some glue onto the plug, and spread it out using the same thin stick. Use very little glue: and excess will be push aside when inserting the plug.
Insert the plug into the shaft. Put it in all the way to the beginning of the shaft. The plug with glue can create a sealed chamber, in which air gets compressed. This compressed air can push out a loosly fitting plug!
Possibilities to avoid this:
- Make sure the plug fits snugly. It there is enough friction, the compressed air will not push out the plug.
- Perforate the chambers in the shafts. If you remove the seal at the internodes (as you might have done to improve drying speed), there will be no air compression.
- Put some scotch tape over the end of the shaft, to avoid the plug getting pushed out.
PU glue is being used to glue to the plug into place. Here, the plug still needs to be pushed in further. The thin stick is used to spread the glue.
Put the shafts away to dry for a while. Best is to have them dry horizontally so the plug cannot slide by gravity. PU glue's dried in as little as six houres.
Clean up the shafs. Take a file to remove the excess glue, and even up the end of the plug with the end of the shaft.
Cleaned up shafts, with the plug clearly visible.
By now, I've made substancial batch of straight shafts. There were thin and thick shafts, so obviously the spine varied within the batch. I wanted better arrows than I currently own, so I needed to make a spine tester of some sort, to categorize the shafts. Most spine testers I've seen online (in drawings and schemes) involve some sort of sensitive "dial indicator". I have absolutely no idea where to get this dial indicator in my country. So I could not find a way to accurately measure deflection.
Other spine testers use a needle/pointer and a lever, as to increase visible deflection, but not measure the deflection of the shaft itself. This was the type I could myself. Also see this thread on PaleoPlanet.
So I used some wood I had laying around. The most crucial part is the needle support. I needed some sort of construction to mount the needle on, and act at the lever. I used some pieces of Ipé I had laying around, and shaped those, drilled holes, and glued metal shafts into.
I think the following pictures explain themselves.
The spine tester with a shaft in position, but not yet "working", as there's no weight on the shaft.
A close-up of the lever mechanism. The copper shaft stays in place, and act as the pivot point. The brass lump on the left end is a counterweight. It is carefully balanced. Underneath the shaft itself, you can see the metal shaft that connects both wooden halves of the needle support. The needle itself is the aluminum tube on the right.
The weight I use to deflect the shaft is nothing more than a brick with a hook I approximately measure the weight, in order to reach 2 pounds of weight (which is the standard in all spine testers). My brick might just as well weight 1,9 pounds, or 2,1. I don't know, I don't care. As long as the same brick is used for all shafts, there will be the same method for measuring spine.
A close-up of the needle/pointer and the scale I wrote on a piece of wood.
In a schematic overview, this is what happens to the needle support. Upper image is WITH the 2# weight hooked onto the shaft. Lower image is without weight. Note the "sliding shaft support", which at all times touches the shaft on the underside. The more the shaft deflects, the more this sliding shaft support pivots on the "rigid pivot point", thus pushing the needle up.
This is the result of some spine testing. These are all the shafts I straightened at the moment. I measured their spine, and wrote down the spine on the shaft itself. When all shafts were done, I put them into groups. Preferably six shafts in one group. Left my weakest shafts (spine up to 35#), on the right the stiffest shafts (spine up to 90#).
Making this spine tester, has given me the following insights I'd like to share with you, in case you want to build a similar spine tester.
- -- My spine tester is accurate enough to match shafts. However, it is NOT accurate enough to indicate if a certain shaft has a spine of 40# or 45#. The scale I wrote down onto the piece of wood, is very inaccurate. I made this scale just by eyeballing the deflection onto a measuring tape. So my current batches of matched shafts are matched in spine, but I don't know exactly how much the spine is. I hope that in practice, this doesn't even matter that much, because bamboo arrows should be not as spine-critical as wooden arrows. Also, an arrow spined to 45# does not mean it only shoots good off a [email protected]" bow. Trial and error should show the best spine for a given bow.
- -- The measurements for the needle support and its pivot points are very important. The lever needs to be just right. I had to make adjustments to the metal rod underneath the shaft.
- -- Balancing the needle is very important. If the brass counter weight was not there, the needle would cause the center of gravity to be on the right side of the rigid pivot point. This would effectively mean that the needle pushes the shaft up. This can be observed when a shaft is in place. If you carefully lift the needle up, you can see the shaft dropping! This means the needle puts weight on the shaft, which is not good. You need to balance the needle in such a way, that pulling the needle up (which causes the "sliding pivot point" to no longer touch the underside of the shaft) does not cause the shaft to deflect more.
- -- You need to rotate the shaft when measuring its spine. If a shaft is not completely uniform in diameter/roundness (and it isn't), you will see variation within one shaft. I always rotate each shaft a few time, to obtain a "spine range" for a shaft. A certain shaft may show a spine range of 43 to 46, while another shaft may show a spine range of 43 to 50! This makes matching the arrowshafts more complicated...
- -- A node [of the bamboo] right in the center of the shaft greatly enhances spine variation within one shaft. A node is never completely round, which means the part of the shaft that deflects most (the exact center), is a bit oval. This causes spine variation to be even higher.
I am using wild turkey feathers for these arrows. I got these feathers at the Bulgaria Euromeet 2008 as a gift
I cut the feathers to size roughly. Use a knife to remove part of the rachis (the big "vein" in the middle of a feather). Some people know how to strip a feather from the rachis. I don't. Admittedly, I haven't even tried it once, but I'm nervous about it. I'm afraid I might mess up these beautiful feathers. Besides this, I've also heard that stripping the feathers leaves only a very thin strip on the feathers, making it more fragile. So I like to use a belt sander to remove most of the rachis, and leave a bit behind.
Feathers before they are sanded. Note the fat rachis.
A few feathers after sanding. The belt sander is mounted upside down, and the feather is moved over the belt.
Nice and thin rachis.
Once the feathers have been cut to length and sanded, you can select the best ones. I look for three similar feathers for one arrow (similar in color, width of the rachis and of course left wing versus right wing). I like to glue the feathers to the shafts using superglue (cyanoacrylate). I do this completely freehand: I don't have a fletching jig.
Applying superglue to the feathers shafts (rachis).
Keeping the feather in place while the glue dries. Takes about 30 seconds to fully cure.
Cut the feathers to size. I use a large pair of scissors for this design, but of course a feather burner will work just as well, especially in curved feathers.
I also wrap the end of the rachis with thread now. Looks much better than without the thread, and it adds a lot of security and safety.
Installing the plastic nock. Once the end has been tapered, I use some polyurethane glue to attach the nock. While the glue is drying, I use a rubber band to lock the nock in place (it's a black rubber band in the picture).
Some black thread is wrapped right after the field tip. This is done to prevent the tip from staying behind in a target.
Finished arrows! only four in the picture: I made six arrows in total though.
Labelled with accurate weight. These came in at about 480 to 520 grains each. I guess the spine is around 55#.