For a long time I've been building Knex bows, with one thing in common. They were all terrible, using elastic bands as a string. But I have finally made a good Knex bow without elastic for a string.
It works exactly like a fyberglass, or wooden, or any other good bow. The power comes from the frame instead of the string. It can withstand a respectable amount of tension and fires a light, fletched kebab skewer with a good amount of force.
Step 1: You Will Need:
3 grey rods
6 yellow 'Half snowflake' connectors
6 green connectors
18 small white rods
10 medium yellow/dark grey rods
12 white 'Snowflake' connectors
26 small blue rods
4 orange connectors
Find more as you need them if I have miscounted. (I'm only human!)
A tub of dental floss
Bamboo kebab skewers
Gloves (For comfort, as the string is very thin, and can cut into your fingers)
Step 2: The Frame (Step One)
Make what you see in the images six times.
Thats 3 for each end.
So you'll have something like this:
Step 3: The Frame (Step Two)
Make this once:
Step 4: The Frame (Step Three)
Putting it together: Follow the diagram.
Do this twice, using 3 for each end.
Step 5: The Frame (Step Four)
Putting together the two ends: Follow the diagrams
Step 6: Making the String & Stringing the Bow
I don't have a definite perfect way to make the ultimate bowstring, and it is usually trial and error until I am satisfied with my string.
ALWAYS MAKE SURE THE STRING IS SHORTER THAN THE BOW!
I will upload a picture of my bowstring, and you will see the loops on each end. I use my doorknob as a spacer-type device, and tie the loop off three times.
This is the hardest and most delicate part of the whole build. You must bend the bow just enough to allow the loop to wrap around the snowflake (Demonstrated in the diagrams) and then seal the loop by snapping a yellow rod in (I've used grey).
Pluck the bowstring when the bow is strung. Does it make a nice, high pitched twanging sound? If so, you've done it! If not, you might want to try and take an inch off the string.
Step 7: Viola! All Done!
Now you're a fully certified Knex archer. Marvel at the power you have, and at how far your bow will stretch back, and propel a kebab skewer through cardboard and other such things.
Cut notches into the back of the kebab skewer-arrows for the string to rest in.
Perhaps search for a 'structable on how to fletch home-made arrows? Your choice. I make some fletchings out of paper and cellotape earlier and was amazed at how straight the arrow went. As long as something guides the airflow, you've got a better arrow already!
I have very steady hands, and even I cut my finger open whilst trying to make the notches. Don't injure yourself!
Finally, NEVER, under any circumstances point this weapon, (Yes, its not a toy anymore, it is a potentially lethal/dangerous weapon now!) at any living creature, human, or object you do not want to damage.
Only use this bow to shoot a target for instance. If using blunt Knex arrows, always be careful is firing at anything, including people. These will not kill, but could take an eye out/bruise somebody. You've been warned!
Please feel free to add any constructive criticism, tips, and maybe a good system to make that perfect bowstring every time!
Leave any feedback in the comments box.