This is my version of a K'NEX switch blade. Before anything, I would like to give credit to slipdiddy101's design or a K'NEX switch blade which I modified and am showing you here today.

Step 1: Getting the Pieces

What you will need:

CONNECTERS:
2--------------------------------Yellow 5-spaced
9--------------------------------Red 3-spaced
1--------------------------------Orange 2-spaced
6--------------------------------Gray Clip 1-spaced

RODS:
1--------------------------------Yellow
2--------------------------------Blue
7--------------------------------White
9--------------------------------Green

SPACERS:
6--------------------------------Blue Thin

OTHER:
1--------------------------------Rubber Band

Step 2: Making the Parts: Body

Take:
4 Red connecters
1 Yellow connecter
2 White rods
4 Green rods

Arrange them like in the pictures.

Make 2 of these.

Step 3: Making the Parts: Blade

Now this won't look exactly like a blade, but pretty close and is really fun to play with.

Take:
1 Red connecter
1 Orange connecter
1 Yellow rod
1 Green rod

Arrange them like in the picture.

(Make 1 of these)

Step 4: Putting Them Together: Part 1

Put 3 white rods on one of the body parts like in the picture.

Step 5: Putting Them Together: Part 2

Put 2 thin blue spacers on the top white rod like in the picture.

Connect a gray clip connecter on the middle white rod pointing inward like in the picture.

Put a gray clip connecter on the bottom white rod pointing towards the other white rods like in the picture.

Step 6: Putting Them Together: Part 3

Connect the other body part to the body part you have been working on by linking it to the white rods, with the blue spacers on the top white rod in between the 2 body parts and the 2 gray clips on the middle & bottom white rods also in between the 2 body parts like in the picture.

Step 7: Putting Them Together: Part 4

Now we will putting the blade on to the body.

Put the hole in the orange connecter on the blade in between the top 2 red connecters on the body with the green piece closer to the 2 blue spacers on the body like in the picture.

Put a blue rod in between the top 2 red
connecters on the body and orange connecter on the blade, locking the blade in place with the body like in the picture.

Put a blue rod on the bottom 2 red connecters as well like in the picture.

Step 8: Rubber Band

Put the rubber band in between the red connecter on the blade and hook the ends of the rubber band to the ends of the top white rod like in the picture.

Step 9: Spacers

Flip the whole thing over now and put 1 blue spacer on both sides of each blue rod like on the picture.

Step 10: Making It Secure

Put a gray clip connecter on both side of each of the blue rods with the blue spacers inside like in the picture.

NOTE: they must have the holes of the gray clip connecters in the ends of the white rods.

Step 11: Your Done!

To put the blade in, connect the red connecter on the blade to the bottom blue rod, but don't snap it all the way in.

To take the blade out, flick the green rod on the blade.

Hope you enjoy this!