Lesson video

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

Our lesson today is Specialist Tools and Equipment for Manufacture, Communal Areas, and this is part of the Iterative Design Student Living Unit.

The outcome, I can manufacture safely using a laser cutter.

There are three key words.

Self-finishing, which is the material does not need additional finishing processes after manufacture.

Nesting, the process of positioning items on sheet material efficiently to minimise waste.

Laser cutter, a machine that uses a focused laser beam to cut or etch designs into various materials.

There are two parts to our lesson, laser cutting, and manufacturing with a laser cutter.

Let's begin with laser cutting.

A laser cutter uses a high-powered laser beam to precisely cut or engrave materials like board, timber, metal, some polymers, and fabric.

A laser cutter works by directing a powerful laser beam through mirrors or fibre optics to a lens, which focuses the light onto a material.

Here, we can see the inside view of a laser cutter, the laser head, and the cutting tray, sometimes called the bed.

Depending on the machine's settings, the laser either cuts through the material or engraves its surface.

We're now going to look at how a laser cutter works.

A powerful focused light called the laser is made inside the machine.

The laser reflects off mirrors to move to the correct location.

We can see the mirror identified in this diagram.

The lens focuses the laser at the point on the material where the engrave or cut will take place, and we can see the lens and the focused laser in the diagram.

A small stream of air blows to keep things clean and cool.

This is labelled on the diagram air assist.

And we can also see identified on the diagram the sheet material.

The focused laser then melts and vaporises the material to produce a cut or engrave.

Powerful extraction is used to remove gases and particles from within the laser cutter.

and we can see the extraction identified on the diagram.

Here we have a check for understanding.

what focuses the light onto material in a laser cutter? Is it A, a mirror, B, a lens, or C, a prism? Pause the video.

Wonderful.

Let's check.

That's right, It's B, the lens, well done.

Laser cutting is an example of cam that can be available within schools and for smaller batch manufacturing.

However, laser cutting is also used on an industrial scale, cutting things such as sheet metal for car bodies or components for aircraft and spacecraft.

For example, cutouts and openings on car bodies can be laser cut.

Laser cutting is also used in construction for cutting large steel beams, or even to manufacture medical devices, such as stents or pacemakers.

Here we can see an enlarged image of a laser cut stent.

We now have a check for understanding.

what can a laser cutter be used for in industry? Is it a, car bodies, B, gears inside gear boxes, C, plastic bottles, or D, medical devices? Pause the video and have a go.

Wonderful, Let's check.

That's right, It's both A and D, car bodies and medical devices.

Well done.

What are the benefits of using a laser cutter? Lucas says, "It can cut out very detailed shapes with self-finished edges, which makes it great for creating neat, high-quality products." Alex says, "Because the laser doesn't touch the material directly, there's less chance of damage, and the cuts are very precise." Sam says, "Parts can be tessellated, which helps reduce waste, saves money, and reduces environmental impact from material use." Laura says, "Laser cutting is often used in schools, factories, and design studios because it saves time and produces consistent outcomes." We now move to Task A, using notes and diagrams, describe how a laser cutter works.

And part two, explain why laser cutting would be a suitable process to make the Christmas decoration we can see here in the picture.

Pause the video and have a go.

Wonderful.

Let's have a look at some of the answers you may have come up with.

Here we can see a diagram of the parts of the laser cutter.

We can see the laser beam, mirror, lens, air assist, the material, and the focused laser.

A powerful, focused light called a laser is made inside the machine.

The laser reflects off mirrors to move to the correct location.

A lens focuses the laser at the point on the material where the engrave or cut will take place.

A small stream of air blows to keep things clean and cool.

The focused laser then melts and vaporizers the material to produce a cut or engrave.

Powerful extraction is used to remove gases and particles from within the laser cutter.

Well done.

And for part two, you may have said, by laser cutting the decoration, you can achieve a detailed design that will be cut out accurately.

Because the laser doesn't actually touch the material, the material will not be damaged, and it will result in a high-quality product.

The laser cutter is also self-finishing.

The laser cutter can also cut the decoration quickly so that many of them can be made in a batch quickly and efficiently.

Well done.

We now move to the second part of our lesson today, manufacturing with a laser cutter.

Here is Alex's design.

The main unit is going to be 3D printed using PLA filament.

We can now see the image of his original sketch that also has hooks included.

The hooks will need to be made using a different method.

Alex considers his options for the hooks.

"I could 3D print the hooks separately.

I could cut out and shape sheet acrylic.

I could cut and shape stainless steel bar." Can you think of any other ideas of how he could create the hooks? To cut and shape the acrylic sheet, Alex could use hand tools, equipment, or CAM.

He could choose to cut by hand using a coping saw and vice, or using a bandsaw.

Saws use serrated blades, which leaves the cut edges rough, and they require finishing with a file and abrasive paper.

Here, we have a check for understanding.

What are the disadvantages of cutting acrylic with a saw? Is it A, it is difficult to control, B, it is inaccurate, C, it is self-finishing, or D, it leaves a rough edge which needs finishing? Pause the video and have a go.

Wonderful.

Let's check.

That's right, it's D, it leaves a rough edge which needs finishing.

Well done.

Another option is to use a laser cutter, which is an example of CAM.

When cutting acrylic, the heat from the laser self-finishes the cut, so no additional finishing is required.

To make 3D prototypes using CAD on a laser cutter, designers need to consider how to turn a 3D design into 2D shapes.

Here is an image of acrylic being laser cut.

Alex has chosen to cut the 2D pieces and then shape them by thermoforming.

He uses a CAD application to draw the different hook shapes needed.

Here is an image of the single hook Alex has designed.

There is a hole to attach to the main unit, and engraved fold lines.

He also designed a double hook and a hanging rail.

He needs three single hooks, one double hook, and one hanging rail.

Alex must now nest the design to ensure it is as efficient as possible and minimises waste.

Nesting is where the shapes are positioned as close to one another as possible.

Sometimes this means the orientation also changes.

Orientation means direction or position.

This is similar to tessellation, but the difference is nesting is different shapes, and tessellation is multiples of the same shape.

The size of the material sheet is guided by the size of the bed of the laser cutter.

Alex's laser cutter has a bed, which is A2 size.

This is 594 millimetres by 420 millimetres.

He would then position all the hooks needed within the sheet of material.

The cut and engrave lines are represented by different colours.

Then he would export his design as a DXF file or an SVG file before importing it into the programme that can communicate with the laser cutter.

Here, we have a check for understanding.

What is the purpose of nesting? Is it A, to move all the pieces to be in the same direction, or B, to move all the pieces to fit as closely as possible, or C, move all the pieces to minimise waste, or D, move all the pieces to spread out on the sheet? Pause the video and have a go.

Wonderful.

Let's check.

That's right, it's both B and C, move all the pieces to fit as closely as possible, and move all the pieces to minimise waste.

Well done.

Alex would then need to adjust the speed and power on the laser cutter so that they are correct for his chosen material and material thickness.

Each colour on the CAD file will require different settings for cutting or engraving.

Speed, this is the speed that the laser travels over the surface of the material, and power is the intensity of the laser.

We now move to Task B.

Part one is to prepare your prototype by drawing the 2D elements using CAD, and two is to source the sheet material and nest the pieces of your design ready for laser cutting.

Pause the video and have a go.

Wonderful.

Let's have a look at some of the answers you may have come up with.

Alex says, "I drew the different hooks and the rail which I need using CAD.

I then copied the single ones and positioned them all as close together as possible to minimise waste." Here we have a summary of our learning today.

A laser cutter uses a high-powered laser beam to precisely cut or engrave materials like board, timber, metal, some polymers, and fabric.

A laser cutter works by directing a powerful laser beam through mirrors or fibre optics to a lens, which focuses the light onto a material.

To make 3D prototypes using CAD on a laser cutter, designers need to consider how to turn a 3D design into 2D shapes.

Nesting is used to ensure waste is minimised.

I'm so pleased you could be here to join me for our lesson today.

Thank you, and well done.