Simple Mechanisms Starter Kit

Instructions Page 1 of 6

Introduction TechCard has been specially developed for use in schools to teach Design & Technology and Science. The newly designed kits are curriculum focused and allow pupils to gain a hands-on understanding of how important simple mechanisms and structures work. These simple mechanisms and structural forms are the basis of our built environment and the mechanical world around us. The TechCard elements are made from sturdy high quality card and are pre-punch and scored for fast accurate model building. The card elements are easily modified to create endless construction possibilities. Building with TechCard allows pupils to gain an understanding of how real structures work as the performance of the material mirrors the real world much more accurately. Plastic and metal construction systems are disproportionately strong and pupils do not experience how strong structures are made. As a simple example, take a TechCard girder and test it’s strength before folding it to shape. Then fold it to shape and you will immediately experience how rigid and useful it has become. This is exact how the steel girders that form our tall building, bridges and cranes work! TechCard allows pupils to experience these principles in their own hands. The TechCard elements are fixed together with unique reusable plastic rivets which make assembly quick, easy and mess-free and a wide range of specifically selected and manufactured mechanical components are supplied with the kits. The new TechCard range of kits consists of five Starter Kits and five Class kits. Each Starter Kit builds three models and can be used to introduce and explore specific curriculum topics. The large Class kits each build twenty models - two each of ten different designs. TechCard kits are uniquely flexible. For example, pupils can follow the instructions to assemble the pre designed models as a ‘focused practical task’ and following this the models can be dismantled and the components used for pupils to ‘design and make’ their own designs. Please check www.techcard.co.uk for more regularly updated information and to forward your questions and suggestions. The new TechCard range include: Starter Kits: Simple Mechanisms, Simple Circuits, Pneumatics, Power Cars and Power Robots. Class Kits: Links & Levers, Build-It, Power-It, Pneumatics and Vehicles.

Teacher’s Notes The Simple Mechanisms Starter Kit explores axles, cams, pulleys and gears in three entertaining models. The models are driven by a crank which drives either a cam, gears, or pulleys. The Simple Mechanisms Starter Kit relates to following curriculum units: Unit 2C Winding Up, Unit 5C Moving Toys, and Unit 6C Fairground. Pupils will learn the need for careful building to ensure components are correctly aligned and to reduce friction. Each model is powered by a crank which creates a turning force on an axle. With the fairground model the direction of the rotating force is changed from horizontal to vertical with a pair of bevel gears. The ‘driving’ gear is smaller than the ‘driven’ gear and so has to travel more than one revolution to make the driven gear revolve once. This arrangement slows the turning force so that the ride turns slower than the crank. With the somersaulting acrobat the opposite is the case. A large pulley is driving a small pulley so for each revolution of the crank the small pulley and the axle fixed to it turns many times. This pulley system is increasing the speed of the rotating force although the direction of the force remains the same. The cam mechanism of the sailing boat model translates the rotating force of the crank into a linear force moving up and down. The particular type of cam used causes the vertical axle to drop each revolution.

The driving gear is smaller and has 40 teeth. The driven gear is larger with 60 teeth. For the large gear to rotate once, the smaller gear has to rotate 1.3 times

For each revolution of the 50mm pulley the small 20mm pulley rotates 2.5 times. However, the pulley system has not created additional speed without cost. The smaller pulley travels faster but with less force than the large pulley. For example if a force of 10 kg were applied to the driving pulley, the small pulley would rotate with a force of 4 kg.

The rotating force of the crank is translated into a linear force by the cam. The cam is a particular type often called a ‘snail cam’ because of its shape. As the cam rotates and passes the highest point in its movement, the rod it is driving drops vertically. Note that this type of cam only rotates in one direction.

Gears and pulleys are similar components with gears having the advantage that they do not slip. Pulleys are among six fundamental mechanisms known as ‘simple machines’. The others are the lever, the inclined plane, the wheel and axle, the screw and the wedge. However, all simple machines can be described as a lever making the lever the single most important mechanical device.

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For building tips, photos & downloads visit: techcardkits.com

© David Eckold 2011

Simple Mechanisms Starter Kit TechCard

Beam

Girder

Strip

Instructions Page 2 of 6

There are six basic TechCard parts that are easy to fold to shape along the scored lines.

Base

Project Base

Chassis

The Project Base has a useful bracket that can be fixed to the base in lots of places.

Forming TechCard Fold the TechCard parts and fix together with the plastic rivets and collars or use glue. (PVA glue is the best) The rivets and collars can come apart and are reusable. Measure between the holes

Modifying TechCard

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TechCard is easy to cut with scissors or a craft knife. You can measure between the holes as a guide. Score TechCard with a craft knife so you can form new fold lines.

Tip: When folding TechCard, fold each panel right over and then return it to the final position. This will give a neat fold of 90 degrees.

Mechanical and Electrical Parts

Motors

Buzzers

Bulbs

Battery Holders

There is a wide range of components that work with TechCard for building exciting working mechanical models. Axles

Axle Plugs

Worm Gears

Spur Gears

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Wheels

Cams

Tyres

Pulleys

Steering Links

Propellers

For building tips, photos & downloads visit: techcardkits.com

Cranks

Foam Washers

Pistons

© David Eckold 2011

Simple Mechanisms Starter Kit

Instructions Page 3 of 6

Preparation for all models Assembling the Project Base 1

2

Place upside down on a flat surface (score lines and printing downwards).

3

5

Fold the side panels upwards. Push the rivets through the holes and slide the rivet collars all the way on.

4

Fold the sides and the tabs at the end of each side as shown.

Follow the steps to fold and rivet the small bracket together.

The bracket can be riveted to the base in many different places and the base can be used in different positions.

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For building tips, photos & downloads visit: techcardkits.com

© David Eckold 2011

Simple Mechanisms Starter Kit

Instructions Page 4 of 6

Acrobat

axles

1

Assemble the project base without the bracket as shown.

2

Cut three axles to the length shown.

3

Position the long axle all the way through the top of the base and the medium axle near the bottom as shown. Push a foam washer on each axle as shown.

4

Fit the small pulley to the top axle and the large pulley to the lower axle.

5

Fit the rubber band over the pulleys.

6

Push the crank onto the axle with the large pulley. Fit a short length of axle into the crank to form an axle.

7

Carefully cut out the acrobat and punch the holes. Carefully fold to shape.

8

Slide the short axle through the arms and body as shown. Slide the acrobat parts onto the axle.

short axle

Turn the crank to operate the pulleys and the acrobat will somersault!

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For building tips, photos & downloads visit: techcardkits.com

© David Eckold 2011

Simple Mechanisms Starter Kit

Instructions Page 5 of 6

Sailing Boat

axles

1

Assemble the project base and bracket as shown.

2

Cut two axles to the lengths shown.

3

Pass the short axle through the base and cam in the position shown. Push a foam washer onto both ends of the axle to hold the cam centrally.

4

Pass the long axle through the bracket and base. Check that is sits on the cam. long axle

5

Push the crank handle onto the short axle. Fit a small piece of axle into the crank to form a handle.

handle

6

Carefully cut out the boat, sails and waves. Punch the holes in the boat

7

Fold the tab on the waves and stick to the top of the base

8

Fold the boat tabs and slide the boat and mast onto the long axle. Stick the sails onto the axle.

crank

Turn the crank and the boat will rise up and down but note that the ‘snail cam’ can only turn in one direction.

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For building tips, photos & downloads visit: techcardkits.com

© David Eckold 2011

Instructions Page 6 of 6

Simple Mechanisms Starter Kit Merry-Go-Round

gear must be this way around

1

Assemble the project base without the bracket as shown.

2

Cut two axles to the lengths shown.

3

Pass the short axle through the base and the small gear. Check the gear is the right way around as shown.

4

Fit a foam washer and the crank to the other end of the axle. Fit a short piece of axle into the crank to form a handle.

axles

foam washer

handle crank

5

Pass the long axle through a foam washer, through the large gear.

foam washer

6

Fit the axle assembly through the base and secure with another foam washer.

7

Check that the mechanism rotates smoothly when the crank is turned. Adjust as necessary.

foam washer to secure axle

9 8

Carefully cut out and fold the parts to the ride and stick the roof along the tab.

Slide the lower part of the ride onto the axle so that it sits on the foam washer. Slide and stick the roof in position and stick the flag to the top.

Check that the two gears are aligned properly. Turn the crank and the Merry-Go-Round will turn.

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For building tips, photos & downloads visit: techcardkits.com

© David Eckold 2011

Simple Mechanisms Starter Kit Carefully cut out the shapes. Cut along the solid lines. Crease and fold along the dotted lines.

Body Panels Page 1 of 1 Acrobat

Fairground Ride

Flag Sail

Arm

Boat

Arm

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Waves

Flag

For building tips, photos & downloads visit: techcardkits.com

Fairground Ride Roof © David Eckold 2011