K'Nex Crossbow
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Introduction: K'Nex Crossbow
This instructable shows how to build a working K'Nex crossbow. Please be smart when using this, it can be dangerous. I suggest not using sharp projectiles and not aiming at anyone. I have a few dents in my wall from early testing.
Step 1: Key
- Build: build from scratch, unless otherwise noted.
- Attach: adding pieces to an existing thing
- Details: nothing new, just a different view
Here are all the parts and names used in this instructables.
Step 2: Parts List
Rods
- 15 Red
- 50 Yellow
- 82 Blue
- 10 White
- 95 Green
- 2 White
- 73 Yellow
- 5 Gold
- 11 Green
- 17 Red
- 60 Orange
- 43 Dark gray
- 35 Beige
- 7 Black rod/connectors
- 23 Silver spacers
- 36 Blue spacers
- 2 Hinges
- 2 Chain links
- 13.5" Orange track
- 40" string (any string that isn't too springy, I use fishing line)
Step 3: Starting Springs
- 16 Yellow connectors
- 12 Red rods
Step 4: Spring (right)
- 1 White connector
- 2 Yellow connectors
- 4 Dark gray connectors
- 1 Green rod
Step 5: Spring (left)
- 1 White connector
- 2 Yellow connectors
- 4 Dark gray connectors
- 1 Green rod
Step 6: Spring (center, Part 1)
- 1 Yellow rod
Step 7: Spring (center, Cut Gold)
- 1 Gold connector
Step 8: Spring (center, Part 2)
- Gold connector from last step
- 2 Red connectors
- 2 Beige clips
Step 9: Main Body
- 47 Yellow connectors
- 3 Gold connectors
- 9 Green connectors
- 4 Red connectors
- 36 Orange connectors
- 36 Yellow rods
- 63 Blue rods
- 72 Green rods
Step 10: Combining Layers and Spring
Temporarily remove the beige clips attached to the yellow beam on the center of the spring. This will allow you to shift the connectors snapped onto it around, making it much easier to connect the layers.
NOTE: Make sure the gold track guide layer is the center layer, connected to the gold track guide connector which you cut earlier.
Step 11: Trigger Housing Start
- 2 Yellow connectors
- 7 Red connectors
- 9 Orange connectors
- 11 Dark gray connectors
- 4 Beige clips
- 2 Yellow rods
- 6 Blue rods
- 18 Green rods
- 2 Black rod/connectors
Step 12: Adding Slidebars
- 3 Dark gray connectors
- 3 Red rods
- 3 Black rod/connectors
- 15 Silver spacers
- 6 Blue spacers
Step 13: Finger Trigger & Mechanism
- 7 Orange connectors
- 12 Dark gray connectors
- 5 Beige clips
- 4 Blue rods
- 10 White rods
- 2 Hinges
Step 14: Partially Assemble Trigger Mechanism
- 3 Blue spacers
- Rubber band(s)
Note the black connector/rods connecting to the white rods in the second picture.
Step 15: Trigger Housing Hinge Guide
- 3 Orange connectors
- 2 Beige clips
- 1 Yellow rod
- 8 Blue spacers
Step 16: Trigger Housing Mid Beam Support
- 2 Green connectors
- 3 Orange connectors
- 3 Dark gray connectors
- 2 Beige clips
- 1 Yellow rod
- 5 Blue rods
- 3 Green rods
- 8 Silver spacers
- 9 Blue spacers
Step 17: Trigger Release
- 2 Orange connectors
- 6 Dark gray connectors
- 4 Beige clips
- 1 Yellow rod
- 4 Blue rods
- 2 Black rod/connectors
- 2 Chain links
- 10 Blue spacers
Step 18: Connect Trigger Housing to Main Body
- 4 Yellow connectors
- 1 Gold connector
- 4 Red connectors
Step 19: Pins & Track
- 16 Beige clips
- 8 Yellow rods
- 13.5" Orange track
Step 20: String
- 40" of string (any string that isn't too springy, I use fishing line)
Step 21: Bolts
Parts for one bolt
- 2 Purple connectors
- 2 Light gray connectors
- 4 White rods
- 4 Blue spacers
Step 22: Done!
Again, I suggest not shooting sharp objects with this, and not ever aiming it at people.
Apart from that, have fun with your new crossbow!
13 Comments
9 years ago on Introduction
I adjusted a few unnecessary parts and it works perfectly. I also build a nice target and I'm enjoying this. Thanks for the design! (y)
12 years ago on Introduction
Nice new trigger system. It looks like the black chain link pieces would be pulled out of the orange connectors if they were pulled so much though. Also I suggest making a new bow (the spring as you called it) such as one powered by counter elastic bands. Check IaC's cannon for reference. Good job.
12 years ago on Introduction
not bad!
Reply 12 years ago on Introduction
Thanks!
Reply 12 years ago on Introduction
no problem!
12 years ago on Introduction
I can see you at least tried to put effort in it but TBH it's doesn't really have a good design.
Reply 12 years ago on Introduction
I know, but this was something I made on a whim and decided to make instructions. I'm planning on improving the design when I have time.
Also, this is only my first K'Nex weapon. I don't have much experience in designing them.
Reply 12 years ago on Introduction
You could have improved the design before you posted it?
Reply 12 years ago on Introduction
Unfortunately no, I was on a deadline. I figured it was better to get good instructions for a early design, instead of spending forever improving the design. I'm planning on upgrading the design and revising the instructions when I have time. I already have a few ideas for that, also suggestions are welcome.
Reply 12 years ago on Introduction
It's actually better the other way around.
Reply 12 years ago on Introduction
It depends on how far you take it and how long you have.
Reply 12 years ago on Introduction
very good first weapon!
Reply 12 years ago on Introduction
Thanks!