Lesson video

Hi there everyone.

My name is Mr. Booth.

And welcome to your design and technology lesson for today.

It's wonderful that you could join me.

Today we are gonna create, modify, and constrain 2D sketches in Fusion so you can extrude those and create some complex shapes.

This lesson is part of the Systems approach to design: Sustainable Futures unit.

In today's lesson, I want you to be able to create 2D constrained sketches using Fusion.

And the word constrained is really important.

In fact, it's one of our key words, so let's have a look at those.

The first key word is sketch, creating basic shapes like lines, circles, rectangles, and text.

We then have modify, using tools such as fillet, trim, and offset.

Constraints, really important when we are sketching, used to control sketch relationships and avoid design errors.

If we are gonna use parametric solid modeling correctly using parameters, we need to constrain our sketches correctly.

We've got two learning cycles today.

The first one is all about sketching fundamentals, and then we're gonna sketch in Fusion.

So let's get going.

Fusion is a cloud-based computer-aided design, manufacture and engineering tool that is used both in design and technology lessons and also in industry.

It's free to all educators and pupils.

It uses parametric solid modeling, creating 3D models as full, solid objects that have volume and mass, so they can be tested using editable parameters.

And those parameters are part of our constraints that we use when we are sketching.

Sketches are 2D geometric representations used to create 3D solid models.

We can't create a 3D extrude, a solid model, without creating a 2D sketch first.

And there are three typical steps to creating error-free sketches in Fusion.

The first one is you've gotta create the sketch.

So you've gotta use lines, circles, or rectangles.

You then might wanna modify it, so you might want to add a fillet to it, or trim, or possibly move.

And then we need to constrain it.

So, we can use constraints such as dimensioning, but we can also use coincident, tangent, and equal.

And we're gonna have a look at some of those.

Quick check for understanding, which is the correct order when creating sketches in Fusion.

Is it A, create, constrain, then modify, B, create, modify, constrain, C, constrain, modify, create, or D, modify, constrain, create? Pause the video now, have a go at this, and come back to me when you've completed it.

It is of course B, create, then modify, then constrain.

Well done.

So, let's see what we need to do to begin a sketch.

Well first of all, we need to be in millimeters, which your Fusion will be defaulted to.

If you're not sure about that, click in the top right-hand corner and go into the quick setup to check that you are working in millimeters.

So first of all, on the solid toolbar, we need to Create Sketch in the Create group.

So just click on that.

Once you've done that, you need to select a plane to actually sketch onto.

And you can see which plane I've selected here because it is shaded out.

Once we've done that, the Sketch toolbar will appear.

So you'll notice your toolbar at the top has completely changed and you've got lots of new tools to play with.

And what we call that is we say the toolbar has become active.

Now, the view will also reorient in front of you and you are now looking on the plane, looking down onto the plane, that you selected.

Now, we need to be able to navigate the Sketch toolbar.

Just like all the other toolbars, you need to know what everything is called.

So let's have a look at that.

So first of all, we have Create.

These are all our lines and shapes that we are going to use to actually create our shapes.

We then have Modify, and that one that we talked about was fillet.

We also have trim in there as well.

We then have our Constraints.

Now, we can constrain using dimensions, but we also have these handy constraints as well, such as tangent or equal.

We then also have the sketch palette.

Now, the sketch palette has lots of other tools that you can use.

We're not gonna use those today, but they are very useful.

We have the origin.

Now, the origin is a great place to start.

That is basically 0,0 in terms of the dimensions in your canvas that you are working in now.

There we have our canvas, which is where we're gonna create our sketches, but also we have our X and our Y axes, which you can see there, which are really handy to use when you are sketching because we can dimension to those.

We can actually constrain to those as well.

So to create a sketch, first of all, we're gonna select line from the Sketch toolbar.

We're then gonna click to place the first point.

And here you can see I've got a GIF of this.

Now I'm gonna start at the origin.

That's a great place to start a sketch.

What we can then do is drag the cursor away and it will preview the line.

You can see I can move it up and down, I can move it around.

And you'll also see I get two constraints.

I get a dimension and I also get an angle of that line as well.

So, I could enter a dimension and enter an angle and that will constrain that line.

Or what I can do is just drop the point anywhere just by clicking.

Now, that's up to you what you wanna do with that.

But you can place the second point and also the angle.

But what we could also do is we could actually snap this to the X or the Y axes if we wanted to, and that would also create a horizontal-vertical constraint.

Quick check for understanding.

Where is a good place to start a sketch? Is, it A on the x axis, B, the Y axis, C, the Z axis, or D, at the origin? Pause the video now, have a go at this, and come back to me when you've got your answer.

It is of course the origin.

That's a great place to start a sketch.

Let's now a look at how we can sketch a shape.

Well, first of all, we need to select a shape from the Sketch toolbar.

So in this case we're gonna do a rectangle and a circle.

Once again, we drop our first point for the rectangle.

We're gonna drop it where the origin is and we're gonna drag away to preview it.

You'll notice we also get some dimensions, so we could enter the dimensions if we wanted to.

Same for the circle.

Click to drop the center point, drag away to see the preview, click if you want to drop the circle at a certain point or enter the diameter if you wish.

Now, to modify a sketch, well in this case we're gonna add a fillet to a rectangle.

So first of all, we need to select the filet from the Modify toolbar.

And then what we're gonna do is we're gonna click the corner where we want to add the fillet.

So you can either click on the corner or you can click on one line and then the other line and it will create the fillet between those two lines.

You can select more than one at once.

We can enter the radius in the dialogue box and then press Enter and you'll get your modification.

Now, let's talk about constraining a sketch.

So we've got two sketches here that are very similar, but they're also very different.

The first one is unconstrained, and let's have a look at what features we can see that means this is unconstrained.

Well, first of all, the lines are blue, meaning they're not constrained.

We've got no sketch dimensions anywhere on this sketch.

Also, we can move those lines.

So, if I grabbed hold of the center of that circle, I would be able to move that within my canvas anywhere I wanted.

Now, let's have a look at a fully constrained shape.

Well, first of all, the lines are black, indicating it's fully constrained.

We also have sketch dimensions on there as well.

And if I try to move any points or lines, I simply wouldn't be able to because they are fully constrained.

Now, to extrude a sketch, it must be a closed profile.

What I mean by that is it must be completely enclosed.

And you can see both of these are closed profiles because they have that light blue fill.

So even though the left-hand, unconstrained shape hasn't got any constraints, you would still be able to extrude that.

But it's best practice to make sure that you are constraining your sketches.

And just to prove that I could move all those parts on the unconstrained shape, there you go.

So, you can see I can change the size of the rectangle and I can also move the circle.

The right-hand, fully constrained shape, I can't move any points or any lines.

They are fixed because it's fully constrained.

And let's just have a look at that one more time.

There you go.

I can't move the circle and I can't move a point on the rectangle.

Fully constrained.

Quick check for understanding.

This sketch is fully constrained.

Is that true or is that false? Pause the video now, have a go at this, and come back to me when you've got your answer.

It is of course false, but why? So see if you can answer that, pause the video again, and come back to me when you've got your answer.

Well, we can see it's not constrained because the lines are blue, there's no sketch dimensions, and if I wanted to, I would be able to move those points and those lines around my canvas.

Well done.

Now, let's have a look how you can constrain a sketch further.

So, we can sketch a rectangle and then what we can do is we can enter the first dimension.

It will automatically do that for you, so you can just enter a number.

If you then press Tab, it will jump to the next dimension.

Because we're creating a rectangle, we need to enter two sides of dimensions, and then we press Enter.

And what will happen is it will give us our dimensions.

To sketch a circle, we can enter the diameter, and that's really easy because again, it will highlight it and let you enter it.

You drop the first point and then enter the diameter and it will give you your diameter.

Now, if you forget to enter the diameter and you drop your circle, you can always press D on the keyboard for dimension, click on the edge of your circle, it will reopen the dialogue box and you can enter a diameter of your choice.

But the circle can also be moved because we've constrained the size of it, but we haven't constrained where it is relative to our rectangle, which is fully constrained.

So, what we can do is we can add two more dimensions.

So we're gonna add one for the X axis and one for the Y axis.

So once again, just press D on the keyboard, select the center of the circle and click on one of the lines of your rectangle, enter a dimension, then do the same again for one of the vertical lines or the horizontal lines depending on which you've done first.

And then what you can do is you can press Enter, and you'll notice your circle is then fully constrained.

If you want to add any modifications, such as fillets, you can do this now, and again, it will ask you to constrain those by using a radius.

Once you've done that and we've finished our sketch, we then need to finish the sketch.

You'll see a big, green button in the top right-hand side of your screen.

So what you do is you click on that.

What I also like to do is once I've exited the sketch, I like to click on the home button because that takes me back into my 3D world.

I can then see my design in 3D again.

Then, on the solid toolbar, we are then gonna select Create Extrude on the Create group.

Once we've done that, we can then select the profile that we want to extrude.

In this case, it's the sketch, but notice I haven't selected the circle.

And then what will happen is it'll automatically extrude our shape.

We can grab the blue arrow, drag it up and down, or enter a distance of the extrude into the dialogue box.

Once we're happy, we press Enter, and then of course what we've done is created our first extrude.

Well done.

So, what we've got here is we've got a video clip of me fully constraining the sketch you can see on your screen.

So, let's watch this and then what we can do is we can get on with our first task.

Let's start by drawing our rectangle.

We're gonna click on the origin as the start point, and then enter our two dimensions of 55 and 80.

We can then draw our circle.

We're gonna roughly place it somewhere but enter the diameter correctly.

And once we enter that of 20, we then need to constrain it using D on the keyboard to create a dimension from the center to the horizontal line, enter the dimension for that, and then from the center to the vertical line, enter a dimension for that.

And then we can modify using a fillet, click on the two lines that we want to fillet together, enter our radius, and that gives us a fully constrained sketch.

So, here we have our first task.

First of all, I want you to explain the three main steps when creating sketches in Fusion.

I then want you to create a new design in Fusion and save it as 'sketch.

' Create a fully constrained complex sketch that can be extruded.

Remember to follow the steps of create, modify, and then constrain.

Once you've done that, I want you to extrude the sketch.

To extrude the sketch, it must be a closed profile.

I then want you to repeat steps four and five, increasing the complexity of your sketch.

Pause the video now, have a go at this task, and come back to me when you've completed it.

So, how did you get on? Well, let's have a look at some sample answers and see if you created a complex sketch.

So first of all, I wanted you to explain the three main steps when creating sketches in Fusion.

So first of all, sketches are 2D geometric representations used to create 3D solid models.

First, the sketch is created using lines, circles, or rectangles.

Then, the sketch is modified using fillet, trim, or move.

Finally, the sketch needs to be constrained using coincident, tangent, or equal constraints.

Now, your sketch and your extrude might look like this and hopefully you made it more complex and hopefully you've managed to be able to fully constrain it and extrude it correctly.

Well done.

Now onto our next learning cycle, sketching in Fusion.

Now of course, editing a sketch, it's important to fully constrain a sketch to avoid design errors, but also we can edit sketch dimensions and constraints using the timeline.

Fusion will then update the model live.

So for example, if I go into my timeline and I look at the sketch that I've just created, and I right click and I edit that sketch, I can then edit things like the circle diameter and also the fillet size.

When I then finish that sketch, it will update my model live, which is very powerful.

Quick check for understanding.

Why is it important to constrain sketches? A, to avoid design errors, B, to increase complexity, C, so models are editable, D, so models are fixed? Pause the video now, come back to me when you've got your answers.

It is of course A, to avoid design errors, and C, so models are editable.

Well done.

So let's have a look at some types of constraints.

Now of course we can constrain using dimensions, but what we can also do is use some of these handy tools, such as horizontal/vertical if you want to make sure your lines are exactly horizontal or vertical.

We have coincidental.

We have tangent if you want to join a line to a circle or a curve.

Equal, if you wanna make things equal.

Parallel, if you want two lines to run side by side.

Perpendicular and fix.

So, fix is useful if you'd want a point not to move.

Midpoint if you wanna snap to a midpoint of a line.

And then we have things like concentric, collinear, symmetry, and also curvature.

But we're not gonna use those quite as much.

Now, if you wanna know a little bit more about these different constraints when you are in your sketch canvas, just hover over each of these and it will tell you lots more information.

So, here we have our sketch.

Now, what we're gonna do now is look at the other types of constraints that are there.

We have our dimensions, but you might have noticed some other symbols appear around our design.

So, first of all, we have tangent.

So these constrain the fillet to the line at a single point.

And you can see it's where that curve is meeting the line.

You can see it's put those in there.

You can also see horizontal as well.

So, we have horizontal/vertical and this is constraining the line to the horizontal or vertical axes that we can see.

Now, what's really interesting is that Fusion actually did these automatically when we created these features because of course it knew we wanted to use them.

And that's really useful when using Fusion.

But you can also add them yourself.

Quick check for understanding.

Which symbol is for the tangent constraint? Is it the symbol at A, at B, or at C? Pause the video now, have a go at this, and come back to me when you've got your answer.

It is of course B.

Well done.

Now sketches can also be created on the faces of components.

In this case, we want to add some ventilation holes to the top of our punnet.

Well, I suppose it's the bottom of the punnet, really, but in this model it's on the top because we flipped it upside down to put it as part of our greenhouse.

Now remember, your model might differ to the one that I have shown on the screen because of course we have iterated it quite a lot.

So, first of all, let's look at how we're gonna add those holes.

With the greenhouse model open, we need to activate the punnet component in the browser.

Now you'll see in the browser there are three components.

There is the base, the punnet, and the microbit you will see in there.

So to activate the punnet, what we need to do is hover over it and then click on that little circle and make sure we've got the dot in the middle.

Now to make our life easier, what we're also gonna do is hide the other components.

We're gonna switch them off and you'll see there is a little eye icon next to some of those components.

So, we are just gonna make sure that the base and the microbit are switched on.

The reason we're doing that, because it can get quite confusing when modeling in Fusion if you've got lots of components switched on.

So, let's just hide those.

And then what we need to do on the solid toolbar, we need to select Create Sketch on the Create group and then click the top face of the punnet.

Now once we've done that, it will take us obviously into our sketch canvas, and then what we do is it will reorient the view so we're looking down on top of our punnet.

Then, what we can do is we can create our sketch.

So I have drawn four holes that are 5 millimeter in diameter and I've just constrained them to the edge of my punnet, the first edge that I can see, by 15 millimeters.

Now when it is fully constrained, you will see it will go black.

This is quite a simple one to do.

When we've done that, we then can click Finish Sketch.

Once we've clicked Finish Sketch, remember I like to click on the home icon next to the view cube, which will take me back into my 3D world.

And then what I'm gonna do is click on Extrude so I can actually extrude these holes through the punnet.

We're then gonna zoom in, so you need to use your mouse skills now.

So, I'm zooming into each of those profiles to make sure I select the correct thing.

Because you can select the wrong thing by accident if you're too far away.

What I also need to do is, once I've selected that first hole, I'm gonna hold Shift down on the keyboard and then I'm gonna work around the top of the punnet, making sure I've selected all four holes.

Once we've done that, in the extrude dialogue box, which you will see on the right-hand side, we're gonna set the distance to -5 millimeters because I wanna cut down into the punnet.

You will see what that will do is that will then change the operation to Cut rather than Add.

We're not gonna add any material into this.

We're not building material, we wanna cut material away.

It will automatically do that if you go down through the punnet.

We're happy with that.

We click OK.

Quick check for understanding.

What do users need to click when a sketch is completed and ready to extrude? Is it A, End Sketch, B, Finish Sketch, C, Complete Sketch, or D, Extrude Sketch? Pause the video now, have a go at this, and come back to me when you've got your answer.

It is of course B, Finish Sketch.

Well done.

So, we're now onto task B.

The first thing I want you to do is sketch four ventilation holes on the top surface of the punnet component.

Holes should be 5 millimeters in diameter, but you could decide on the placement.

I then want you to ensure that the sketch is fully constrained.

Extrude the holes through the top surface of the punnet component, so, you need to Cut.

The component is 0.

5 millimeters thick.

I then want you to discuss why it is important to constrain sketches in Fusion fully.

And then finally, a user would like to constrain two lines so they run side by side.

Explain which sketching constraint would be suitable.

Pause the video now, have a go at this task, and come back to me when you've got your answer.

So, let's see how you got on.

Well, hopefully your punnet now looks something similar to mine with four holes that were fully constrained as a sketch in the top surface of the punnet, and they have been extruded through the punnet.

So, cut through.

I then wanted you to discuss why it is important to constrain sketches in Fusion fully.

First of all, it is important to fully constrain a sketch to avoid design errors.

Users can also edit sketch dimensions and constraints using the timeline.

Fusion will then update the model to show the changes made and it'll do that live.

That's really powerful.

Finally, a user would like to constrain two lines so they run side by side.

Explain which sketching constraint would be suitable.

Well, of course the parallel constraint would be suitable as this will constrain the line so that they extend in the same direction and never intersect.

Now, remember that users can find constraint information by hovering over the constraints when sketching.

Well done today.

You've been absolutely fantastic.

That brings us to the end of today's lesson.

Let's have a quick summary.

Fusion is a sketch-based CAD application based on parametric solid modeling.

In Fusion, sketches are 2D geometric representations used to create 3D solid models.

There are four sketch tools in Fusion, create, modify, constraint, and of course, there is palette as well.

Constraints should be applied to sketches to avoid design errors but also make your designs fully editable at any stage using the timeline.

Well done today.

I look forward to seeing you all next time.

Goodbye.