Y8 DT EOY exam

Question 1

define an mechanism

Answer 1

a mechanism is a device designed to transform
input forces and movement into a desired set of
output forces and the movement.

Question 2

what are the 4 types of motions and their meaning

Answer 2

Rotary motion =
0bject rotates

Reciprocating motion =
0bject moves back and forth or up and down

Linear motion =
0bject moves in a straight line

0scillating motion = 0bject swings backwards forwards and up and down

Question 3

name 4 cams and their shape,

Answer 3

Pair: an egged shaped cam
Circular: a circle shaped cam
heart: a heart shaped cam
Drop/snail: a half oval with a drop on top creating a half circle
Ellipse Cam: Oval-shaped cam.
Double Cam: Two cam profiles on one shaft.

Question 4

what is a cam and followers

Answer 4

A cam is a rotating part with a special shape that controls the movement of a follower.

Question 5

what are levers and their job

Answer 5

A lever is a bar that turns around a fixed point called a fulcrum to move a load with less effort.

Question 6

what is a class 1 Lever and give an example

Answer 6

A Class 1 Lever has the fulcrum in the middle, with the load on one side and the effort on the other. (Seesaw)

Question 7

what is a class 2 Lever and give an example

Answer 7

A Class 2 Lever has the load in the middle, with the effort on one side and the fulcrum on the other. (Wheel barrow)

Question 8

what is a class 3 Lever and give an example

Answer 8

A Class 3 Lever has the effort in the middle, with the load on one side and the fulcrum on the other. (Tweezer)

Question 9

what is a linkage and what are they for

Answer 9

A linkage is a system of connected levers that can change the direction or type of movement.

Question 10

what are the 4 linkages type and their motion

Answer 10

Reverse Motion Linkage: Changes linear motion to the opposite direction.

Bell Crank Linkage: Changes motion by 90 degrees (e.g., vertical to horizontal).

Sliding Linkage: Moves parts in a straight line along a track.

Parallel Motion Linkage: Keeps two levers parallel, both move in the same direction.

Question 11

what are gear trains and their job

Answer 11

Gear trains are two or more gears connected together to transfer motion and force from one part of a machine to another.

Question 12

what are gear ratios and their job

Answer 12

Gear ratio is the comparison of the number of teeth on two connected gears Controlling speed and torque in a gear system

Question 13

what are Pulleys and belt and define their job

Answer 13

Pulleys are wheels with a grooved rim that a belt fits around.

A belt is a flexible loop that connects two or more pulleys.
Transfer rotary motion from one pulley to another

Change the direction of motion
Change speed and torque between pulleys depending on their size
Allow motion to be transmitted over a distance

Question 14

what are compound, Idler and output gears

Answer 14

Compound Gears: Two or more gears fixed together on the same shaft, so they rotate together. Used to achieve bigger changes in speed or torque within a small space.

Idler Gears: Gears placed between the driver and driven gears to change the direction of rotation without affecting the gear ratio.

Output Gears: The gear at the end of a gear train that delivers the final motion or force to do the work.

Question 15

give an example of a softwood tree and their properties

Answer 15

• (Fir Tree)
• stays green and grows all
  year round
• Cheap compared to
  hardwoods
• Wide grains

Question 16

give an example of a hard wood and their properties

Answer 16

• (Oak Tree)
• Deciduous (Loses its
  leaves annually (autumn))
• Slow growing
• Expensive compared to
  softwood
• Narrow grains

Question 17

what are 4 examples and reason for softwood

Answer 17

• Cedar contains natural
  oils offering water resistance

-Spruce has a high stiffness to weight ratio

-Larch is durable, tough good water resistance

-Pine is lightweight and easy to work with

Question 18

what 3 are uses and reason for hardwood

Answer 18

Beech is tough and very durable with a fine finish

Oak is tough, hard and durable with a variable grain

Ash is very tough, but also flexible and shock resistan

Question 19

define a
- quick return system
- Crank slider

Answer 19

Quick Return System: Mechanism with slow forward and fast return stroke.
Crank Slider: Linkage that turns rotary motion into linear motion.

Question 20

define Isometric

Answer 20

Isometric’s a 3D drawing method where all axes are 120° apart, keeping scale equal and angles look different.

Question 21

Define Housing Joints and their uses

Answer 21

used to fix shelves or partitions into cabinets or bookcases. The housing is cut across the grain, usually as wide as the thickness of the inserted connection piece

Question 22

what are Lap joints

Answer 22

members overlap. joining 2 pieces of materials:
-Corner Lap Joints’s useful
for joining corners
-Butt Joint provides nailing
or screwing surfaces, more
gluing area reducing
exposed.End Grain

Question 23

Tenon Saw

Answer 23

allows you control over depth and direction of cut typically for precision ( e.g Furniture making) so used with softwoods and hardwoods.

Question 24

what are Tenon and mortise joints

Answer 24

A strong wood joint where a tenon (a rectangular end) fits into a mortise (a matching hole or slot).

Question 25

Bench hook

Answer 25

a  work bench  appliance for  woodworking holding a  workpiece  in place while cutting  with a  hand saw. improving accuracy and safety.

Question 26

name 4 manufactured boards

Answer 26

- Chipboard - Plywood - Hardboard - Medium Density Fibreboard (MDF)

Question 26

File

Answer 26

A hardened steel bar or rod with small cutting edges on its surface, used in metalworking to smooth or form objects by rubbing against the workpiece

Question 27

marking gauges

Answer 27

accurately transferring measurements to wood

Question 28

Steel rules

Answer 28

produce accurate measurements, also used as guides for lines, rigid ones could be used for cutting. flexible ones could measure rounded work.

Question 29

Mallet

Answer 29

hammer with plastic or hardwood head for striking tools or wood without damage (e.g. Hardwood or Plastic Bossing Mallets).

Question 30

Chisel

Answer 30

A metal cutting tool with a sharp edge, driven by a mallet or hammer to shape or cut materials.

Question 31

Pillar drills

Answer 31

used for accurate, vertical drilling into materials. allowing adjustable speed and depth, making it ideal for repeated or precise work.

Question 32

Coping saw

Answer 32

A C shaped saw with thin, narrow blades for intricate wood cuttings

Question 33

Glass paper and how their grits scale work

Answer 33

- A type of abrasive paper with surface coated in crushed glass for smoothing or shaping materials - Higher grit = smoother finish - Lower grit = rougher, faster cutting

Question 34

Disk sander

Answer 34

A round abrasive paper on a spinning plate, used to shape wood, smooth edges, round corners, and quickly remove lots of material.

Question 35

Belt sander

Answer 35

A power tool with a moving abrasive belt used to quickly smooth or shape large flat surfaces.

Question 36

Briwax

Answer 36

Cleans and protects wood, available clear or in eight shades to stain and wax at once. Used in pine furniture; apply with steel wool, brush, or cloth.

Question 37

label cam, follower, crank and camshaft

Answer 37

Cam: Rotating shaped part. Follower: Moves up and down on the cam. Crank: Connects camshaft to cam. Camshaft: Rod that spins the cam.

Question 38

what is a datum

Answer 38

a key geometric feature (point, line, plane, etc.) on an object used as a reference to define or measure its shape.

Question 39

tri square

Answer 39

A tool with a metal blade and handle used to check or mark 90° angles on materials.

Question 40

what are Figurine, static feature and riser in a CAM toy

Answer 40

figurine: the moving character static feature: the non-moving part (e.g. base, background) riser: rod that transfers motion from the cam to the figurine.