Introduction: K'NEX Catapult
Reading the instructions are just as important as looking at the pictures. Simply looking at the pictures to build your catapult could lead to catastrophic failure and a possible safety issue. We suggest you read all instructions, but just in case you don't critical steps in the building process will be noted with the words "Critical Step, read instructions first".
The K’nex catapult can be assembled in many ways, but the easiest way is to build 4 sub-parts (as shown above) and then connect them all together at the end.The 4 sub-parts include the front base, the back base, the middle base, and the catapult arm. There is no required sequential order in regards to which sub-part to built first. The instructions for each sub-part’s construction are displayed below along with descriptive pictures of each step.
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Step 1: Catapult Arm Assembly
Required pieces for catapult arm assembly:
- 2 White connectors
- 3 Blue rods
- 2 Red rods
- 1 Yellow connectors
- 3 Black rods
- 3 Gray rods
- 7 Orange connectors
- 19 Grey connectors
- 2 Red connectors
- 2 Tan connectors
Step 2: Making the Catapult Basket
Connect 3 blue rods and 2 red rods to 2 white connectors in an alternating fashion as shown. Spread the white connectors as far apart as possible so that the basket has a maximum opening This completes the basket portion of the catapult.
Connect a yellow connector to the two red rods on the opposite end of the of end of the basket and then connect a tan connectors on the end of each red rod.
Connect 2 black rods on the ends of the yellow connector and then slide another black rod in the center circle of the yellow connector. Slide all of the black rods away from the basket.
Connect 2 red connectors to the outer 2 black rods as shown in the picture. Then slide an orange connector between the 3 black rods such that the middle rod runs through the hole of the orange connector and the outer 2 rods snap into place. Slide the red and orange connectors towards the basket.
Add 2 orange connectors to the 3 black rods as shown and slide them towards the basket.
Add 3 more orange connectors to the black rods as shown.
Critical step: read instructions first! Slide all of the orange pieces to the towards the basket and then add 19 gray connectors to one of the gray or black arms as shown. This step prevents the orange connectors from moving thus stabilizing the arm. This completes the catapult arm assembly.
Step 9: Back Base Assembly
- 5 red rods
- 5 yellow connectors
Connect three red rods in parallel using 4 yellow connectors.
Connect the 2 other red rods together with the last yellow connector.
Now combine the parts assembled in steps 1 and 2 making sure all rods and connectors are snapped firmly together to complete the back base sub-part.
Step 13: Front Base Assembly
Required Pieces for front base assembly:
- 3 gray rods
- 3 white rods
- 3 tan connectors
- 14 yellow connectors
- 2 white connectors
- 10 red connectors
- 5 gray connectors
- 2 blue space rings
Connect 3 gray rods in parallel using 8 yellow connectors and slide the yellow connectors together as shown. Notice that 4 connectors keep the 3 rods held together while the other 4 connectors are attached on each on the outer rods.
Attach the 5 gray connectors and 1 tan connector to the middle gray rod in between the 2 sets of yellow connectors as shown. Note: the directionality of the tan connector does not matter
Link two white connectors using 1 white rod.
Attach the white connectors from step 16 towards the end of the middle gray rod rod as shown. Then slide all pieces of the middle gray rod towards the end with the white connectors.
Attach 6 yellow connectors facing down to the middle gray rod and slide them towards the other yellow connectors on the middle rod.
Critical Step, read instructions first! Connect 10 red connectors to the middle gray rod next to the yellow connectors as shown to fit snugly on the middle gray rod. This step should prevent movement of all pieces connected to the middle rod.
Connect 1 tan connector to a white rod and then add a space ring. Repeat this step twice.
Now insert in the 2 pieces from step 20 into the circles of the yellow connectors on each side of outer gray rods of the front base assembly as shown. This then completes the front base assembly.
Step 22: Middle Base Assembly:
Required Pieces for middle base assembly:
- 10 orange connectors
- 8 yellow connectors
- 4 red rods
- 1 blue rod
Insert a red rod through the center hole section of 3 yellow connectors. Then connect 2 orange pieces to the red rod such that all of the yellow connectors are in between the 2 orange connector as shown
Connect 2 yellow and 2 orange connectors to a separate red rod as shown.
Critical step: read instructions first! Align the pieces from step 23 and 24 such that the yellow connectors from step 23 alternate between the yellow connectors from step 24. The orange connectors from step 24 need to fit between the orange and yellow connector from step 23. Connect both parts from step 23 and 24 as shown below. Note the orange connectors from step 23 face the opposite direction of the yellow connectors from step 24.
Critical step: read instructions first! Slide 6 orange connectors evenly on a separate red rod and space them apart. Then align the inner 4 orange connectors to alternate between yellow connectors from step 25 and align the outer orange connector on each side fit outside the orange connectors from step 25 as shown.
Snap together the components from step 25 and 26. Then slide all pieces as close together as possible.
Insert the last red rod through the center hole of 3 yellow connectors. Then attach 1 blue rod to the end of the 3 yellow connectors as shown.
Critical step: read instructions first! Finally, attach the component from step 28 to the component from step 27 such that the yellow connectors from step 28 alternate between the orange connectors from step 27 and that the blue rod from step 28 is on the same side as the orange connectors from step 23. This completes the middle base assembly.
Step 30: Combining the Sub-parts
Now that all of the sub-parts have been constructed the last couple steps is to connect them all together.
Align the middle base and the front base as shown.
Connect the gray rods of the front base to the yellow connectors of the middle base.
Connect the white rods of the front base to the orange connectors of the middle base.
Attach a blue rod to the 2 yellow connectors of the middle base as shown and then slide a gray connector on the bottom red rod of the middle base.
Attach the blue rod from the front base to the gray connector on the middle base.
Repeat steps 34 and 35 on the opposite side of the catapult.
Align the red rods of the back base such that they can connect to the middle base. Then attach the back base to the middle base by connecting the 5 red rods of the back base to the 5 yellow connectors of the middle base.
Attach the black rods of the catapult arm to the yellow connectors of the middle base such that the arm is on the opposite side of the attached blue rod. Make sure the catapult basket faces in the upward direction.
Step 39: Firing the Catapult
Wrap the 2 rubber bands around the red rods of the catapult arm.
Sling the other ends of the 2 rubber bands around the white rod at the front of the front base. Make sure you hold down the front base with one hand while you do this.
Load up the catapult basket, pull the arm back and let go to fire the K’nex catapult! For best results, hold one hand on the front base while firing the catapult.