Lesson video

Hello there.

My name is Mrs. Dhami.

Thank you for joining me for your design and technology lesson today.

Now the big question for today is how can timbers be finished effectively? We're going to explore a whole range of different methods, and then you can pick which ones might be suitable for different applications.

So hard hats on.

Let's get cracking.

Our outcome for today is we will be able to explain and compare small-scale and industrial finishing processes.

We have three keywords today: finishing, which is a process that adds surface treatment to improve how a material looks, feels or performs; aesthetics, which is how the product looks, including color, texture, and style or theme; and lastly, function is what a product should do to be successful.

We have two learning cycles today.

Small-scale finishing processes moving on to industrial finishing processes.

So we're gonna start off with small-scale finishing processes.

Finishing is the final stage in working with timber.

It serves three main purposes: protection, for example, from moisture, UV rays, insects, et cetera; aesthetics, enhances the appearance of the timber, for example, staining to bring out the grain; and lastly, function, makes the surface easier to clean, more durable or non-slip in some cases.

Timber is a natural material that can degrade over time.

Suitable finishings: seal pores to stop moisture from entering, reduce wear and tear, improve product lifespan, and make products suitable for specific environments such as outdoor use.

So finishing timber can give it water-repelling properties, and you can see that clearly in that picture where the water is just about to roll off.

Time for a quick check-in.

Which of the following is not a reason for finishing timber? A, to extend its durability; B, to improve its appearance; C, to make it biodegradable; or D, to protect it from moisture.

Have a think.

Come back to me when you've got an answer.

Well done if you manage to get C.

C to make it biodegradable is not a reason for finishing timber.

There are several timber finishing types.

I'm gonna start with wood stain.

So wood stains change the color of the wood, but it still shows the grain, so it doesn't cover up the grain.

It is commonly used on decorative items. However, the protection level is minimal.

We then move on to varnish.

Now varnish adds a protective coating to improve function and can have different textures like matte or gloss.

It is used on tabletops and outdoor items, and its protection level is strong, much stronger than wood stain because it gives that whole top protective coating.

Moving on to wax.

Wax gives a soft sheen and brings up the warm aesthetic tones in timber.

It is commonly used for indoor furniture and can come in a range of tints.

Protection level is moderate.

We then have oil, now oil soaks into the wood to nourish and protect it.

Oil is also food safe, which is why it is often used to enhance the function of serveware and chopping boards.

So if you buy a new wooden chopping board, you are often encouraged to get some oil and to coat it onto the surface.

Protection level is moderate.

Moving on to paint, paint adds color, but also at the same time as a protective layer.

It also comes in a range of finishes.

These finishes can range from matte to eggshell, satin, semi-gloss to gloss.

And as we move along that scale, they get shinier and shinier till we get to gloss.

Paint is often used on children's toys where bright colors and durability form an important part of its aesthetics and function.

So not only does it look good, it's also durable.

Protection level is strong.

Time for a quick check-in.

Which finishing type is best for a wooden outdoor bench exposed to the weather and all the elements? Is it A, wax; B, varnish; C, oil; or D, stain? Have a think.

Come back to me when you've got an answer.

Well done if you got B which is varnish.

Varnish is suitable for a wooden outdoor bench exposed to the weather.

There are benefits and limitations associated with different finishing methods.

Let's take a look a little bit more closely.

We'll start with stain.

The benefits are it enhances the grain without hiding it.

The limitation is it often needs a top coat for protection.

Varnish, benefit, it is tough and provides long-lasting protection.

Limitations, it can peel over time or yellow if it's oil based.

Wax, benefit is it provides a natural look.

Limitation, low durability.

Oil, benefit is easy to apply and reapply.

Limitation, it needs regular maintenance.

And lastly, paint.

Benefit, it provides strong protection.

However, a limitation is it hides the beautiful natural grain.

Before applying a finish, the timber surface must be properly prepared, otherwise it will result in a poor outcome.

So how do we do this? Step one, we sand the wood, the timber, by hand or by using a palm sander, by using progressively finer grit sandpaper.

So for example, we might start at an 80 grit and finish at a 240 grit, 240 providing a much smoother finish.

Smooth wood means the finish can stick better and be applied more evenly.

We also, part two, must remove the dust, 'cause obviously sanding creates a lot of dust.

So we remove the dust using a clean dry cloth to ensure the surface is clean.

Time for a quick check-in.

What is the correct order when preparing timber for finishing? Is it A, clean, sand, apply, finish; B, apply, finish, sand, clean; C, sand, clean, apply, finish; or D, apply, finish, clean, sand? Wow, that was a mouthful.

Have a think, decide and come back to me when you've got an answer.

Well done if you got C.

The correct order when preparing timber for finishing is sand, clean, apply, finish.

There are several small scale methods for applying a finish.

We have brushes, brushes are easy to control and can be used with paint, oil, stain and varnish.

We have waxes and oils that can be applied with a clean lint-free cloth.

We have spray paints that provide an even coat over larger surface areas.

And then this one's a great one.

The friction from buffing machines is also useful for applying wax.

So it gets right into those tiny little gaps by the grain.

When finishing timber, it is always important to consider the following health and safety aspects.

Ventilation, some finishes release fumes called VOCs, which stand for volatile organic compounds.

PPE, which stands for personal protective equipment such as gloves, goggles, or masks.

And then lastly, storage.

Some finishes are flammable and require adequate storage.

And you will have a special storage facility at your school for storing those type of liquids and sprays.

Time for a quick check-in.

What does PPE stand for? Is it A, personalized protective equipment; B, personal protective equipment; C, preventative protective equipment; or D, personal preventative equipment? Have a think.

Come back to me when you've made a decision.

Well done if you've got B, PPE stands for personal protective equipment.

Onto task A, part one.

Explain one reason why timber is sanded before applying a finish.

Part two, describe two finishing types and compare their advantages.

Part three, a student wants to protect a pine desk that will be used daily.

Recommend a suitable finish and justify your choice.

And lastly, part four, describe one method of applying a timber finish and explain one health and safety consideration for this method.

Good luck.

Come back to me when you've got some wonderful answers.

Part one, explain one reason why timber is sanded before applying a finish.

You might have said sanding smooths the surface of the timber so that the finish can stick better and create an even and aesthetically-pleasing coating.

Part two, describe two finishing types and compare their advantages.

You might have said one method is using oil which enhances the grain of the wood.

It also soaks into protect from within.

Another is wax, which gives a soft, natural finish and is ideal for indoor furniture.

However, oil offers better protection over time.

Part three, a student wants to protect a pine desk that will be used daily.

Recommend a suitable finish and justify your choice.

You might have said varnish would be suitable because it creates a hard coating that resists scratches and wear from everyday use.

It also protects against spills and moisture.

Part four, describe two methods of applying a timber finish and explain one health and safety consideration for each method.

You might have said one method is using a brush to apply varnish.

This gives good control and is useful for flat surfaces.

A health and safety consideration is ensuring good ventilation, as varnish can release harmful fumes.

Well done with all your efforts on these questions.

Onto learning cycle two, industrial finishing processes.

Industrial finishing is the large-scale application of finishes to timber products during mass production.

These processes are often automated and are designed for high speed and volume, quality and consistency, and have a cost effectiveness by reducing the amount of human labor required.

Industrial processes are, of course, efficient, but they're often less flexible than hand finishing.

In industry, finishing is integrated into the production line using conveyor systems. Items move through each finishing stage such as sanding, cleaning and inspecting the product.

Human workers work inside spray booths and apply the finish using spray guns or robotic arms program to complete a repetitive task and ensure consistency in application.

And lastly, number three, UV or heat curing chambers that dry finishes quickly.

Automation in industrial finishing ensures consistency, so there's quality across hundreds or thousands of units.

Speed, so multiple items are finished in seconds.

Precision, robotic arms apply uniform coats.

And waste production, controlled spraying reduces overspray which uses less chemicals so there's less waste and less effect on the environment too.

Time for a check-in.

What is one main benefit of using robotic arms in timber finishing? Is it A, they apply finishes with consistent quality; B, they sand the wood slower than by hand; C, they make timber more durable; or D, they reduce the cost of raw materials? Have a think, come back to me when you've decided on an answer.

Well done if you got A.

A main benefit of using robotic arms in timber finishing means that they apply finishes with consistent quality so that they all look the same.

Surface preparation essential in industrial manufacturing to ensure finishes are applied consistently and efficiently.

Before finishing, timber products are sanded to consistent dimensions and smoothness, cleaned often using air blasts to remove the dust, and then they're checked automatically using sensors for function and flaws.

Time for a check-in.

Why is surface preparation important in industrial timber finishing? Is it A, it improves the color of untreated wood; B, it helps the finish stick evenly and prevents defects; C, it removes natural oils from the wood; or D, it makes the timber more lightweight? Have a read through.

Have a think.

Come back to me when you've made your decision.

Well done if you got B.

Surface preparation is important in industrial timber finishing because it helps the finish stick evenly and prevents defects.

Lacquer is a coating that is used to protect and enhance the appearance of indoor wood, for example, furniture or musical instruments.

And you can see the absolute shine on that lacquer on the wood on that instrument there.

Now lacquer is thinner than varnish, which means it can be applied using a spray gun.

It also dries more quickly which makes it ideal to use in an industrial setting.

Industrial finishing allows timber products to be made in a wide range of colors, helping companies make aesthetic trends and preferences.

Primers are often used before paint or lacquer because they seal the timber to stop the paint soaking in unevenly.

They improve adhesion of the top coat, and they hide imperfections allowing for brighter color application.

So how does it work? Number one, the surface is prepared.

Two, prime.

Three, color coat.

And finally, the top coat.

Time for a check-in.

Why is a primer often used before applying paint to timber in industrial finishing? Is it A, to make the wood last longer; B, to darken the natural wood grain; C, to seal the surface and improve adhesion of the top coat; or D, to waterproof the timber permanently? Have a think, come back to me when you've made your decision.

Well done if you got C.

A primer is often used before applying paint to timber in industrial finishing to seal the surface and improve adhesion of the top coat.

Health and safety is an important consideration in industry so that workers are protected.

Measures include enclosed spray booths with extractors, ventilation systems for VOC control, and PPE for human workers in manual finishing stations.

PPE covers things such as respirators, gloves, and overalls.

Manufacturers need to consider the impact that producing products in volume has on the environment.

Considerations include VOCs, which stand for volatile organic compounds, which come from solvents which can cause air pollution.

Instead, they can use water-based or low-VOC alternatives.

Finishes have chemicals that can pollute waterways, so waste paints, varnishes, et cetera and wash-off water must be treated before being released into the water system.

Time for a check-in.

What does VOC stand for, and why is it a concern in timber finishing? Is it A, very old coating, it reduces quality; B, volatile organic compound can be harmful to health and the environment; C, vacuum overcoating used for sanding; D, varnish oil composite creates a strong seal? What a mouthful.

Have a think which one is correct.

Come back to me when you've got an answer.

Well done if you've got B, VOC stands for volatile organic compound, and it can be harmful to health and the environment.

Onto task B, part one.

I would like you to name one method of applying a finish in industrial timber production, and explain one reason it is used.

Part two, compare two advantages of industrial finishing over small-scale finishing.

Three, a company wants to finish 10,000 identical timber panels quickly and with a professional look.

What process should they use and why? And lastly, four, explain one environmental consideration that manufacturers must take into account when finishing timber products on an industrial scale.

Good luck with your answers.

Come back to me when you've got some great ideas.

Part one, name one method of applying a finish in industrial timber production and explain one reason it is used.

You might have said spray guns are used because they apply finishes quickly and evenly across many products, saving time.

Part two, compare two advantages of industrial finishing over small-scale finishing.

You might have said industrial finishing is much faster, allowing thousands of units to be processed per day.

It also offers more consistent results because machines apply the finish evenly every single time.

In contrast, hand-finishing can vary depending on the person applying it and often takes more time.

Part three, a company wants to finish 10,000 identical timber panels quickly and with a professional look.

What process should they use and why? You might have chosen conveyor lines with robotic arms applying the paint, then using a heat chamber to dry.

This allows high-speed application of an even finish and ensures all 10,000 units look the same, which is important for quality control.

Part four, explain one environmental consideration that manufacturers must take into account when finishing timber products on an industrial scale.

You might have said, "Waste materials like leftover finishes and cleaning solvents are disposed of responsibly.

These must be treated properly to avoid contaminating water supplies or harming ecosystems." This brings us to the end of our lesson today.

Let's summarize what we have found out.

Finishing improves timber's aesthetics, function and durability.

Small-scale methods use hand tools and are flexible for custom work.

Industrial finishing uses machines for speed, consistency, and higher volume production.

Both must consider health and safety and environmental issues like VOCs.

Well done with all of your hard work today, and I hope to see you in another lesson soon.

Take good care.

Bye-bye-bye.