Hello, my name's Mrs. Taylor and thank you for joining me for today's lesson.

Today's lesson is Fabricating Manufacturing Processes and this is part of the Principles of Materials and Manufacturing unit.

The lesson outcome is: I can identify different fabrication methods suitable for specific materials.

And we have several keywords today: fabricate: which means to join materials together; mechanical fixing: which is a component which joins materials together; adhesives: joining materials together using sticky substances; deformation: a change in shape of objects due to physical forces acting upon them; and friction: the force that resists motion when the two surfaces come into contact with each other.

We have two learning cycles: Fabricating materials safely, and Choosing adhesives and mechanical fixing.

Let's start.

Materials can be joined in different ways.

Joining materials can also be known as fabricating.

The main two methods of fabricating are: adhesives and mechanical fixing.

Adhesives are sticky substances, often called glue.

Here we have some examples: a glue stick, a glue gun, some PVA glue, which is an abbreviation for polyvinyl acetate; and some Tensol cement.

Let's have a check.

Which of these are not examples of an adhesive? Is it A: PVA glue, B: Tensol cement, C: Thread, D: screw? Pause the video and have a go.

Well done.

Let's check.

That's right, thread and screw are not adhesives.

Glue sticks and PVA glue are water based.

They absorb into the materials, such as papers and boards and timber to join them together.

They are relatively safe to use.

Glue guns heat up solid glue into a hot liquid.

This hot liquid glue joins materials such as polymers, timber, and card together once it has cooled.

It is often used for modelling as the glue is brittle once set and therefore not very durable.

The glue also adds thickness to the join as it is quite a solid, thick layer when applied.

We are now going to watch a video of a glue gun being used.

We can see the glue coming out of the nozzle, leaving a thick layer, and then when joined together, it creates an immediate bond.

Tensol cement is applied to materials such as acrylic polymers.

The glue produces a chemical weld and creates a permanent joint when pressed together.

The fumes can be harmful, so you must be in a well-ventilated area and replace the cap immediately.

This must also be stored in a locked metal cabinet.

Tensol cement may also irritate skin, so you should use a brush to apply and consider wearing gloves.

Which adhesive is most suitable for joining papers and boards? Is it A: PVA glue, B: a glue gun, or C Tensol cement? Pause the video and have a go.

Well done.

Let's check.

That's right, it's PVA glue.

Well done.

Mechanical fixings are required when a stronger fabrication is needed to join materials.

This could be through friction, which is the force that resists motion when the surface of one object comes into contact with the surface of another.

Screws and bolts are examples of mechanical fixings, which rely on friction.

The thread of the screw, which are the spiral ridges, press against the timber where friction occurs and creates a strong join.

The thread on a bolt presses against the internal thread of the nut, and this is where the friction occurs.

Rivets and staples are mechanical fixings which rely on deformation, which is a change of shape of objects due to physical forces acting upon them.

Rivets are deformed to create a tight sandwich of metal around the material being joined.

Staples change shape to curve round when the stapler is pressed.

Here we have another check.

What is a main reason for using mechanical fixings? Is it A: Colour variety, B: Durability and strength, or C: Low cost? Pause the video and have a go.

Well done.

Let's check.

That's right.

It's durability and strength.

Adhesives and mechanical fixings can be risk assessed.

A risk assessment considers the potential risks and then states actions which will minimise these.

For example, this table shows part of a risk assessment for using a fret saw.

The potential risk is dust and the action to minimise the risk is to have appropriate machine and room extraction, to wear personal protective equipment, known as PPE, which would include an apron and goggles.

Here's an example of a stapler risk assessment.

The potential risk is that your fingers may become trapped and the action to minimise this is to be aware of the correct hand placement before operating.

Another risk is that scratches or cuts from loose staples might occur, and the action to minimise this is to check the stapler base plate is in place as this ensures the sharp staples are folded neatly.

Here we have your first task, Task A, part one: For two of the fabrication methods, identify the potential risks.

And the second part is to state the actions which could be taken to minimise each of these risks.

We're now going to watch the video of a glue gun in use, and we're also going to watch the video of riveting using a rivet gun.

It's important to make sure you keep your hands away from the hot nozzle indicated by the orange colour and the hot glue as they can cause burns.

Notice also that the cable is behind where we are working and will not touch the hot nozzle and become damaged.

Here we can see the rivet being positioned in the two pieces of card which we're riveting together and then placed in the rivet gun.

Then we must squeeze the handles together.

It's important to make sure that you hold that carefully and you don't squeeze your fingers in between.

The other thing that it's important to be aware of is that the end of the rivet is discarded at the end and must be put in the bin and not left around to cause a slip hazard.

Well done.

Let's see how you got on.

Here we have the potential risks of using a glue gun: Hot glue on your hands, and the action to minimise this would be to train the operator to avoid touching the glue.

Another risk could be that the electric cable gets heated and damaged, so the action to minimise this would be to use the glue gun in an area with space to move the nozzle away from the electric cable, but also to place the glue gun in a stand or use the built-in stand when not in use.

Another potential risk is that the hot nozzle will burn your hands, and to minimise this risk, place the glue gun in the stand or use the built-in stand when not in use and train the operator to recognise the hot nozzle.

Here we have the risk assessment for a rivet gun.

The potential risk is trapping your fingers and the action to minimise this is to be aware of the correct hand placement before operating.

Another potential risk is the rivet debris.

Action to minimise this risk is to ensure the rivet gun is used just above a workbench to ensure the waste pin does not fly across the room.

Collect all the waste pins and dispose in the bin to ensure they are not a slip hazard.

And here we have the risk assessment for Tensol cement.

The potential risk is the fumes, so the action to minimise this would be to work in a well-ventilated room, to replace the lid immediately and to store in a locked metal cupboard.

Another potential risk is that it may come into contact with the skin, so always use a brush to apply and consider wearing gloves.

Well done.

We now move on to the second learning cycle, which is: Choosing adhesives and mechanical fixings to join materials.

The choice of fabricating method depends upon the materials you are trying to join.

Metals are often welded.

Polymers are often joined using adhesives.

Timbers are often mechanically joined.

However, they could all be joined using adhesives or mechanical fixings.

A quick check.

What affects the choice of a fabrication method? Is it A: the colour of the material, B: the material properties, or C: the product price? Pause the video, have a go.

Let's check.

That's right.

It's the material properties.

Joining lollipop sticks.

Who is right? Aisha says that "Adhesives will absorb into the wood and join them effectively." But Lucas says, "Mechanical fixings may split the lollipop sticks as they are thin timbers." They are both correct.

Joining lollipop sticks.

Which type of adhesive? Adhesives have been chosen to join the lollipop sticks.

Some adhesives work better for different materials.

To find the most appropriate fabricating techniques, we can conduct tests.

Here are the materials and tools needed to test different adhesives: A glue gun, PVA glue, a glue stick, some masking tape, some sticky tape, some lollipop sticks and some masses.

Which of these will you not need to test adhesives? Is it A: lollipop sticks, B: masses or C: split pins? Pause the video.

Have a go.

Let's check.

That's right, it's split pins.

Task B.

Here is a test.

Different adhesives are used to join two lollipop sticks.

The join is then tested by applying masses to them, and we're now going to watch the video of an example.

Here we have the lollipop sticks suspended from two bricks.

The masses are hooked onto the lollipop sticks using a pipe cleaner to connect them.

Here we have Task B.

Part one: Which fabrication technique do you predict will be the strongest and hold the greatest weight before breaking? And explain why.

And part two: Conduct the test.

Test joining two lollipop sticks together using different adhesives and add the mass each one could hold before breaking to the table.

And part three: Write a conclusion explaining if your prediction was correct or not.

Explain why.

Fantastic.

Let's have a look.

Part one: Which fabrication technique do you predict will be the strongest and hold the greatest weight before breaking? And explain why.

Aisha said, "I think the glue gun will be the strongest join because it is really hard once it dries." And Lucas says, "I think the masking tape will be the strongest if it is wrapped all the way round the join because it will cover more area than a spot of glue." Part two: Test joining two lollipop sticks together using different adhesives.

And here are some results: The mass before breaking for PVA glue was 1,200 grammes.

The mass before breaking for a glue stick was 100 grammes.

The mass before breaking for a glue gun was 1,100 grammes.

The masking tape was 900 grammes, and the sticky tape was 1,000 grammes.

Number three: write a conclusion explaining if your prediction was correct or not.

Explain why.

Aisha says, "The glue gun was almost the strongest.

PVA was stronger, but this takes a long time to dry.

The glue gun works well if you need to be quick." And Lucas said, "Masking tape wasn't the strongest.

If I used more and wrapped it round in layers, it may have been stronger." Here we have a summary of our learning today in the fabricating manufacturing processes lesson: Materials can be joined using adhesives.

Different materials require different adhesives.

Adhesives can be water-based, hot liquid, or chemicals.

Materials can be joined using mechanical fixings, which are often stronger than adhesives.

Mechanical fixings may work through friction, such as screws and bolts, or through deformation, such as rivets and staples.

Thank you for joining me today.

And really well done.