Pipes, Try-Squares and Surface Gauges

Question 1

What is a surface gauge usually used for?

Answer 1

• Scribing parallel lines as it’s base is heavy which means it’s stable when on use
• Finding the centre of a piece of round section

Question 2

Explain how the centre of a piece of round section is found

Answer 2

The round section steel held in a vee block. The surface gauge is then moved across the surface of the steel, scribing a line. The steel is then rotated through 90 degrees and another line is scribed. This is repeated until a square is produced in the centre (see diagrams below). Diagonal lines are then drawn from each corner of the square to locate the exact centre of the circle

Question 3

A spring is used to bend a tube/pipe to form a curve. What is likely to happen if a spring is NOT used?

Answer 3

The spring prevents the tube wall from collapsing or becoming distorted. Without the spring, the tube may break when bent

Question 4

If a sharp 90° angle is needed in piping, a corner joint is used. Describe how this is done

Answer 4

The joint can be soldered into position using a simple blow torch, flux and solder

Question 5

A corner/curve can be formed in a pipe without the need for a spring or corner joint. Although the technique isn’t the most accurate way of forming a bend in a pipe, what is it?

Answer 5

The pipe is filled with grains of sand as they prevent the pipe from distorting as each grain is irregular in shape, making it difficult for them to be compressed

Question 6

Where are copper pipes commonly found?

Answer 6

In the home being used for water supply plumbing. These pipes will be shaped in a way that doesn’t take up much space

Question 7

Describe the stages involved in forming pipes using a pipe bender

Answer 7

• The tube is first positioned in a straight grooved block - this holds it in place securely
• The lever arm is then rotated, bending the pipe slowly to the shape of the rounded channel

Question 8

What type of pipes can a pipe bender form?

Answer 8

Copper, aluminium and steel pipes

Question 9

What are the three main parts of a pipe bender?

Answer 9

Grooved block, lever arm and a rounded channel

Question 10

How does a typical engineers try square differ from a typical woodworkers try square?

Answer 10

The stock on a woodworkers try square is usually made from rosewood with a brass face

Question 11

What material is used to manufacture an engineers try square?

Answer 11

Mild steel

Question 12

The blade of a try square is specially treated. What is this treatment called?

Answer 12

Tempering

Question 13

Why is the blade of a try square treated?

Answer 13

So that it resists damage

Question 14

A try square and a scribe are used to mark out metals. Describe the marking out procedure

Answer 14

The try square is pushed against the side of the material and a scribe is used to scratch a line on the surface of the metal

Question 15

An engineers try square has been designed to include a small slot. Why is this slot essential?

Answer 15

The slot prevents small burrs caused by filing from altering the try squares accuracy, however, if the burr fits into the slot and does affect the way the try square is used, the slot may not be needed

Question 16

What is the blade of a woodworkers try square typically made from?

Answer 16

Steel

Question 17

Why is the blade of a woodworkers try square hardened and tempered?

Answer 17

It makes the blade more resistant to damage

Question 18

Why does the stock of a woodworkers try square have a brass face?

Answer 18

It ensures a straight edge as the rosewood stock may be uneven

Question 19

Describe how a quality check can be performed using a try square

Answer 19

The try square and material are held up to the light and the try square is moved along the length of the wood. If light shines through any gaps between the blade and the wood, then the edge is not square