PowerPoint Presentation

KNEX SET: Knex Man & Crank-up Knex Truck

By Jan Andrew G. DonatoENGIN25SPRING 2015

What is Knex?Knex, like legos, is a toy building system that is comprised of rods, connectors, gears, and various other components which can be used to build a variety of models, machines, architecture, etc. It is commonly used in schools to enrich students with a basic understanding of physics, mathematics and functional mechanics.

Why Knex?Reasons why I had picked knex:Nostalgic project to do that would be fun and time consuming.Incorporates originality through building your own models and designs.Creativity (Build-it-yourself).

Commonly used PartsParts that would be reoccurring in my model will be the rods and connectors. The rods and connectors come in various sizes and shapes but follow the same orientation for how they are put together.

Connector PiecesFeatures: Extruded, Circular pattern, Extruded cut

Each of the parts shown all derive from the same part. Each of these parts were made using the circular pattern feature.

RodsFeatures:Extruded Cut, Revolve

The rods follow the same sketch design. With the bottom parts of the rod being dimensioned and sketched the same way. Each rod varies in size, with all rods being rotated from the origin.

Unique ComoponentsThe wheel component allowed traction for the model. Through the use of gears, the model was able to move freely. Unlike the other parts that had followed the same orientation, there are some unique parts that allowed movement through the use of joints and joint connectors or even motion through the use of gears and wheels.

GearsThese gears were created through the use of the extrude and rotation feature and function together with the use of the gear mates. When connected to the crank and wheels, the gears were able to be propelled forward.

Frame Connector rodsThese pieces are a hybrid of both the connector and rod components. These components helped give the model a durable frame which also stabilized the connected pieces together.

Knex man piecesThe knex man, is a subassembly of the truck. It is comprised of joints and joint connectors, a torso, knex chin, eye, and forehead components.

Socket Joint, joint connector, handsThese parts are used to build the arms and legs of the knex man. Unlike the connector parts, these parts have specified uses. When the socket joints and joint connectors are mated together, they are capable of moving in any direction and are able to twist and turn in order to adjust to leg and arm movements. The hand parts can be also be used to connect to socket joints can also be used to connect to rod pieces.

Forehead, Eyes, Chin Knex man componentsThese parts make up the head of the knex man and are joined together by a white rod. The head is able to spin in a complete 360 turn.

Knex body (Torso)The knex torso is the main part of the knex man and is a central part for all the components since it is able to connect the head piece, arms and legs together. This piece was made using extrusions, fillet, chamfer, revolve base feature.

Knex man Exploded View

Knex man Assembly schematic

Truck Assembly Unlike the knex man, the knex truck is built in with a variety of rods and connectors and also includes a built in crank-up gear which allows the car wheels to function and move forward.

Truck Drawings

Mate errors When working with the project, I encountered errors with interference where parts would meld within the features of the parts. Many of my parts were accurately measured using calipers. Reasons why these parts when mated to one another become this way is because with the actual knex set, when the pieces are attached to one another, the parts would either bend to fit in the rod connections. This ties in with elastic modulus.

Thank you!