Lesson video

Hello, I'm Mrs. Taylor.

And I'm really pleased you can join me for our lesson today.

Our lesson today is "Plan manufacture using orthographic projection: textiles." And this is part of the "Iterative design: Nature" unit.

We have five keywords.

Orthographic, represents a 3D object in 2D, where views are projected from the object's surfaces.

3rd angle, a type of orthographic drawing.

Construction lines, guidelines used in drawings.

Dimensions, numerical values that specify the size.

Scale, a ratio of full size.

Our outcome.

"I can prepare an orthographic projection of my design." We have two learning cycles, planning an orthographic projection, and creating an orthographic projection.

Let's get started.

An orthographic projection represents a three-dimensional object in two dimensions.

Views, such as front and side, are projected perpendicular to the object's surfaces.

They are sent from a designer to a manufacturer to enable them to manufacture the product or component of the drawing.

Orthographic projections are completed before the manufacturer.

Let's have a check.

An orthographic projection represents A, a 3D object in 3D.

B, a 2D object in 3D.

Or C, a 3D object in 2D.

Pause the video and have a go.

Fantastic.

Let's check.

That's right.

It's a 3D object in 2D.

Here is an example of an orthographic projection.

Orthographic projections can be in the 1st or 3rd angle.

The positions of the views in the drawing are dictated by the angle.

3rd angle projection aligns more naturally with how objects are observed in real life.

Here we have a symbol for 3rd angle projection.

Please note the centre lines.

Let's have a quick check.

Identify what is missing from the third angle projection symbol.

Pause the video and have a go.

Brilliant.

Let's check.

That's right.

It's the vertical centre line, which was missing.

The arrangement of the projections are shown below.

The front, bottom left.

The plan, directly above it.

And the side, directly beside it.

We also add an isometric three-dimensional drawing.

The distance between the front and plan projections should equal the distance between the front and side.

There are different line types on orthographic projection.

Outlines are dark, solid black lines.

Construction lines are grey or faint pencil.

Hidden detail is equal space dashed line.

Dimension arrows are a solid black line with arrows at either end.

And the centre line is a long and short alternate dashed line.

Construction lines are guidelines that help create projections.

Centre lines to indicate the centre of holes and symmetrical objects.

Dimension lines are lines with arrowheads and a numerical value that specifies size.

Hidden detail, dashed lines that are not visible from the current viewpoint.

And outlines to represent the visible edges and boundaries.

Let's have a check.

Describe the appearance of the different lines used on an orthographic projection.

Pause the video and have a go.

Brilliant.

Let's check.

Outlines, solid black line.

Construction lines are grey or faint pencil.

Hidden detail, equal space dashed line.

Dimension arrow is a solid black line with arrows at either end.

And a centre line is a long and short dashed line.

Well done.

Orthographic projections are created using a scale and this will be recorded on the drawing.

A scale is the ratio between the dimensions of a drawing or model and the actual dimensions of the object it represents.

Reduced scales like 1:2 or 1:5 are most likely to be used, meaning the drawing is smaller than the real object.

Dimensions are numerical values that specify the sizes in the drawing.

They are written once on the page, and all dimensions are in millimetres.

A dimension arrow is used and the measurement is written above and in the centre of the line.

For example, the symbol for a diameter dimension is a circle with a diagonal line through it.

Task A, label the following on the drawing.

The projection names, the different line types, the 3rd angle projection symbol, a dimension, and the scale.

Pause the video.

Well done.

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

The plan, top left.

Front, bottom left.

Side, on the right.

And isometric, top right.

We have dimension line at the top, 250, with the arrows either end.

Outlines, the solid black lines.

Construction lines are the faint or grey lines.

Centre line is a long and short dash.

Hidden detail is an equal spaced dash.

We also have the scale, which, on this example, is 1:2.

And the 3rd angle projection symbol.

Well done.

We move on to the second learning cycle, creating an orthographic projection.

Here is a design for a planter in an isometric view.

To create an orthographic projection, start by obtaining a sketch of the front projection and applying a suitable scale.

In this example, a suitable scale is 1:5.

The arrows highlight the different projections used to create the orthographic drawing, the front, the plan, and the side.

Align the front projection in the bottom left corner.

Add construction lines that support creating the plan and side projections.

Let's have a check.

Identify the name of the view and projection for the design below.

Pause the video and have a go.

Well done.

Let's check.

The view is an isometric, and the projection is the front.

Well done.

Sketch in the plan and side projections applying scale.

Let's have another check.

What is the name of the lines that support creating different projections? A, dimension.

B, hidden detail.

C, construction.

Or, D, outlines.

Pause the video and have a go.

Brilliant.

Let's check.

That's right, it's C, construction lines.

Add lines for hidden details, centre and dimension lines, and dimension values to the relevant parts.

Extension lines can be added to show dimension extents.

For example, an isometric view of the product is added.

Construction lines can now be removed.

To finish the orthographic projection, a title block is added.

This contains details about the drawing like below, who created the drawing, the date at which it was created, the fact that all the dimensions are in millimetres, the correct projection symbol, in this case, 3rd angle, the scale in this example is 1:5, it's drawing number one, we can see which company created it and the signature of the creator.

This is an example of a final orthographic projection with all the components as we've described.

Task B, create an orthographic projection for a design idea inspired by nature.

Use the success criteria.

Use an isometric sketch to create a front projection whilst applying a suitable scale.

Add construction lines to support creating the plan and side projections.

Add all relevant dimension, centre and hidden detail lines.

Add and fill in a title block with details including the scale.

Pause the video.

Fantastic.

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

Your answer could look like this.

Here is a summary of our learning today.

An orthographic projection represents a three dimensional object in two dimensions and is completed before the manufacturing stage.

A type of orthographic projection is 3rd angle projection and consists of a front, plan and side projection along with an isometric view.

There are many different line types on an orthographic projection including dimension and construction lines.

Projections are created using a scale and this will be recorded on the drawing in a title block with other drawing details.

Thank you for joining me today.

And really, well done.