Hello, and welcome to today's Design and Technology lesson.

My name's Mrs. Fletcher, and I'm here to help and guide you through your learning today.

Today's lesson is called Make an Electric Vehicle Chassis, and it's part of the Pulleys and Gears: Electric Vehicles unit.

In this lesson, we'll begin the process of building our prototype electric vehicles, and we'll start by building the frame.

We'll be looking at the skills and the resources and steps that we'll need in order to do that.

So let's get started.

The outcome of today's lesson is, I can build an accurate vehicle chassis.

So we'll be getting started on putting together the pieces we need to build a frame of our vehicle, and that keyword, accurate, in that outcome means that we'll need to make sure that we are measuring and cutting very carefully to make sure our vehicle fits together properly.

There are some keywords and phrases that we'll need to use in today's lesson, so let's have a look at those together before we start.

So first of all, we've got that word, chassis, and when we're talking about the chassis, we're talking about the frame or the base onto which the rest of the vehicle is going to be built.

So it's a very important part of the vehicle that we're going to be building today.

Then we've got the word, accuracy, and this is one of the key skills that we're going to be developing today.

When we're being accurate, it means we're being exact and we are not making any mistakes, and that's very important when we come to measuring and cutting in order to build something, that we are being exact and we are not making any mistakes with our measurements.

Then we've got the word, parallel, and that means things that run side by side, but they never meet.

So particularly when we're talking about lines that are parallel, they run in the same direction, but they don't touch.

And then we've got the phrase, axle holder, and that's going to be part of the chassis we build today, and that's a device that holds an axle in place.

So that's gonna be an important part of today's build.

Today's lesson is split into two parts.

First of all, we're going to be preparing the components of our vehicle, and then we're going to be moving on to assembling the chassis itself.

So let's get started with preparing the components.

So a chassis is a frame or a base onto which the rest of the vehicle body is built.

And the chassis for prototype electric vehicle, like the one that we are building today, is made up of two main parts.

We've got a wooden frame, and then we've got some cardboard support that we'll use to help support other parts of the vehicle later.

And Jacob is saying here that it could be a good idea to use recycled materials to make our prototype.

So we use offcuts of wood or some cardboard that's been used before, we can recycle that for a new purpose for this.

That's a really good idea, Jacob.

So when we are thinking about the shape of the chassis that we're going to make, it depends on the design of your vehicle.

So there are different shapes that we might build in order to change the shape of the vehicle up from your design.

The instructions in this lesson are going to focus on making a rectangular chassis, but you can change the shape by altering the size of the wooden sections as we go along.

So you can follow the steps, but you might need to alter some of the sizes if the design of your vehicle does not follow a rectangular base.

A quick check before we move on then.

Are we sure what a chassis is? Is a chassis a recycled cardboard support? Is a chassis the body of a vehicle, or is the chassis the vehicle's frame or base? Pause the video, have a think.

Welcome back.

What did you think? Well done if you said, "It's the vehicle's frame or base." Well done.

Okay, so these are the resources that we're going to need to get started building our chassis frame.

You're going to need some cardboard, cut into a rectangle which is 30 millimetres by 40 millimetres, and again, we could use recycled card for that.

You're going to need four cardboard triangles, cut out to fit the corners of our frame.

We're going to need some PVA glue.

A joiner is optional to help hold your pieces of wood in place.

And we'll also need five lengths of 10-millimeter square section wood, which we'll cut to the correct size.

So if you are making an alternative chassis shape, so not the rectangle that I'm going to go through, you just need to make sure that you have five pieces of square section wood that makes two sides, a front, a back, and a middle support.

So whatever the shape is, you need to make sure you've got those five sections.

You need to make sure you've got four triangular cardboard supports, which you might need to tweak the shape of, depending on the shape of your chassis.

And you need to make sure you've got one rectangular cardboard central support, which, again, might need to be cut to a different length than the one I'm going to use in order to fit across the centre of your chassis.

So as long as you've got those things in place, then you can follow the steps along with me.

All the components do need to be measured accurately to fit your design.

So when you're using a measuring tool to make sure you're measuring accurately, you need to remember a few things.

You need to make sure you start measuring with the zero in the correct position.

You need to make sure that that is lined up accurately with the edge of the wood or the cardboard that you are measuring.

And you need to accurately read or mark the length using the correct integers, so that's the small lines on your ruler or the decimals when you need to record it.

So you can see here, if I was just looking quickly at that measurement, I could say it's 120 millimetres, but if I actually look very carefully, wanting to be accurate, looking at the integers on that ruler, I can see that, actually, it's 118 millimetres, it's not quite 120 millimetres, and that can be important when you come to cut your pieces of wood and card.

They won't fit together if we are one or two millimetres out on every piece.

So make sure you are accurate with your measuring when it comes to this task.

A quick check then about measuring, if this line measures 13.

5 centimetres, how many millimetres is that? So you through a little bit of converting centimetres into millimetres.

Is 13.

5 centimetres 13 millimetres, 135 millimetres, or 130 millimetres? Pause the video, and have a think.

Welcome back.

Did you manage to work it out? Well done if you said, "It's 135 millimetres." So there are 10 millimetres in a centimetre, so we've got 13 whole centimetres, so that's 130 millimetres, and then we've got 0.

5 of a centimetre, half a centimetre, which is five millimetres, so 135 millimetres altogether.

Well done if you got that right.

You need to make sure that you double-check your measurements when we are completing this task or when you're doing any measuring tasks, before you make any permanent changes.

So specifically if you're going to saw a piece of wood, make sure you double-checked your measurements before you do that because you can't put it back together again afterwards.

So, measure, mark, and then measure again to make sure that you've got those measurements correct.

So these are the tools and equipment we're going to need to cut the square section wood to the correct size to start building our chassis.

So you're going to need a bench hook to hold your pieces of wood in place.

You're going to need some sandpaper to get rid of any rough edges once you've cut your wood into shape.

You're going to need a junior hacksaw, which is the safest type of cutting tool to use for this task.

You can use some safety goggles if you want to.

You'll need a clamp to hold your bench hook into place.

And again, you can use a joiner if you want to to hold those pieces of wood in place as well.

Once you've got those things together, you'll be ready to start.

When we are learning to saw wood, there are a few key things that we need to remember.

Safety, accuracy, and technique.

So we need to be safe, we need to be accurate, and we need to use the correct techniques to make sure that we are doing it properly.

So being prepared and using those correct techniques ensure that we stay safe, and accuracy ensures a quality finish to our work, so we're gonna get a good product at the end.

Jacob and Sophia here are getting ready to cut some wood.

And to stay safe, they've remembered to tie back any loose hair, to roll up their sleeves, so they're out of the way of getting caught in any of the equipment.

They clear the table, so they've got room to work, they gather together all the tools they need before they start, and they could also wear goggles and apron if they wanted to as well.

Now, Sophia and Jacob have chosen to wear goggles for this task.

The hacksaw blade on the hacksaw that you're going to use today has very small teeth, which is what actually makes it cut through the wood.

And the teeth point very slightly backwards, and they cut through on each pull stroke that you do.

So every time you drag it across the wood, those teeth cut through the wood.

And it's very important that hacksaws are carried down by your side at all times when you're moving around with it.

It should be held by the handle, and it should be pointed down at the floor, and that's to keep you and everyone around you safe, so there's no accidents.

Jacob then positions the bench hook on the table, so this is where we get ready to start sawing the wood, and then this should be secured with a clamp, so it doesn't move.

And a bench hook is just a block that sits on the edge of the table, and it's used to hold the wood in place.

Rather than trying to keep it clamped to the table, which could damage the table and move around, it's a secure and safe place to keep the wood.

Sophia then pushes the piece of wood that they're going to cut up against the top of the bench hook.

And she's using her non-writing hand to hold that in place.

So that means, if you are left-handed, if you write with your left hand, then the piece of marked wood that you're going to cut should be on the left.

And if you're right-handed, so you use your right hand to write, then the piece of marked wood should be on the right side of the bench hook, because you're going to use your writing hand to hold the saw, so the wood needs to be in the right place for you to saw it carefully.

Jacob makes sure that he's holding the saw correctly before he starts, and this is very important.

You need to rest your index finger, so you pointing finger, along the top or side of the saw, and that pointed finger helps with accuracy because it keeps the saw steady, it stops it from moving too much, which means the line that you're cutting will stay in the same place, you don't get too much movement there.

So you can see from the pictures there how to hold that saw using your finger to steady the tool.

And you're going to make an indentation first.

So an indentation is like a little groove, a little mark, to show where you want to cut through.

And to do that, you place the hack saw on the pencil mark that you've made to show where you want to cut, you make sure your fingers are out of the way of the blade before you move it at all, you pull back on the hacksaw once, so you drag it backwards towards you across that piece of wood, and then you lift and put the hacksaw back in the same place where you started, and you repeat that three times, and that will help to keep the blade in place when we come to saw properly through the wood because we've got that little mark that we've made that will hold the blade in the correct position.

Your body position is very important when you are learning to saw as well.

You need to make sure you're stood correctly in order to saw accurately and safely.

So you need to stand with your left foot forward unless you are left-handed, in which case, you'll stand with your right foot forward.

You need to use your whole thumb to hold the piece of wood in place.

You can see there in the little video that the thumb is what's holding that piece of wood in place, and the rest of your fingers are gripping that bench hook, and that's what will keep that piece of wood in place.

You need to position the saw in that cut, that indentation that we've just made, and you need to tip it forward just slightly.

The saw will work better if it's slightly angled and not completely flat in that indentation.

And then you're going to move the saw backwards and forwards slowly.

So you're going to drag it backwards and forwards across the piece of wood.

You're going to use the middle of the blade, so make sure it's positioned, so that the middle of the blade is what's doing the work, making sure you keep your fingers away at all times.

So don't move your fingers during the sawing, keep them in that position.

Make sure you don't hold onto the saw too tightly.

You need to make sure you relax your grip a little bit.

Otherwise, it will make the saw get stuck in the wood.

So relax and try and do smooth forward-and-backward motions, and that will make it much easier.

So these are the steps then for sawing your wood safely and accurately.

You're going to measure it first to the size that you need, mark it with a pencil, clamp the bench hook to your table, position the wood in the correct position, make an indentation by dragging the saw backwards, and then saw through your piece of wood carefully and accurately.

Once you've done that, you need to position your pieces of wood together to check that you've cut them into the correct size.

So this is the five pieces of wood that we need for our chassis.

Just loosely position them together, so you can check that you've got the right pieces and that they are going to fit together.

So it should just look a little bit like this, slightly different if you've got a different chassis shape.

So that's your task then for this first part of the lesson.

So to start with, you're going to use those steps to accurately measure and mark out the five pieces of square section wood that you're going to need for your chassis.

If you're making the rectangular chassis along with me, then that means you'll need three pieces that are 100 millimetre length and you'll need two pieces that are 150 millimetre length.

If you're doing an alternative chassis shape, then you will need to measure how big you need your pieces to be.

So the steps then are to line up the edge of your wood on the zero of your ruler, mark a line at the correct integer, making sure you are being very accurate, and then double-check all your measurements to make sure that you've got five pieces ready to cut that are accurately measured.

Pause the video while you complete that task, and then come back when you're done.

Welcome back.

So you should have your five pieces of square section wood measured out now.

So the second part of the task is to cut them into the separate sections.

So you're going to use the steps for cutting wood safely that we went through earlier on in the lesson.

And you're going to cut the sections that you measured and marked.

For the rectangular chassis, that following along with me, you should have two 150-millimeter pieces that are separated and three 100-millimeter sections.

And then this is where as Sophia's reminding us here, "You could use your sandpaper to just smooth it off any rough edges from the sawing." So you've got five pieces of wood ready to go.

Pause the video while you do that, and then come back when you're done.

Welcome back.

How did you get on? So you should have now cut your wood.

So you've got two side sections, whichever length you were cutting them to, and one section each for the front, middle, and back support.

So you should have five sections of wood.

These are the measurements for the rectangular chassis here.

But if you've got an alternative shape, then you might have different sizes of wood there.

Well done if you've managed to complete that task.

We can move on to the second part of the lesson, and this is where we'll be looking at assembling those pieces to make our chassis.

So let's just remind ourselves the resources we need for assembling our chassis.

You're going to need that cardboard rectangle, which, if you're following the rectangular chassis, will need to be 120 millimetres by 30 millimetres.

If you've got a different-shaped chassis, you'll need to measure across that middle section of your chassis in order to get the size for that rectangle.

You'll need four cardboard triangle support, again, they might need to be slightly altered if you've not got four right angles, as I will have on my rectangular chassis.

You'll need some PVA glue.

You can use a joiner to hold the wood together if you want to.

And you're going to need an A5 piece of card.

Now, you can use absolutely any piece of card that you want.

It's a good idea to use recycled card.

There's all kinds of card you can use, some already has holes in, some's quite thin.

You can use corrugated card.

I would recommend a thicker card for this task, it provides more support to your vehicle, but you can use any piece of A5, just make sure it's cut to that A5 size.

So this is where we're going to be joining and strengthening our wooden frames.

We're gonna join together those pieces that we've cut, and then strengthen it to provide the base for our vehicle.

So first of all, you're going to make sure you've got those five sections of wood, then you're going to glue together two of the pieces, so I recommend starting with the side piece, which will be the 150-millimeter length, and glueing that to one of the shorter front piece or back piece, which would be 100 millimetre.

And you're glueing it at a right angle if you're following the rectangular chassis.

And then you're going to use the cardboard triangle to cover that joint.

So you glue the pieces together, and then put the glue, the triangle, into the corner as well.

And you're going to repeat that with two more pieces, so another long piece and a shorter piece.

So then you've got the two sides joined to a front and a back piece.

And you should be left with just the middle piece, separate at the side.

So you'll have two L shapes of wood now.

Then you're going to glue those two sections together and cover the joins that you've just made with cardboard triangles again.

So it should look like this if you're following the rectangular chassis.

Then you're going to add the central supports, this is that separate piece of wood that we had.

You're going to glue it into place first, so this is where we need to make sure we were accurate with our cutting and measuring, because if it's not accurate, it may not fit into that gap, or it may not reach the sides in order for you to glue it.

So we need to make sure it's touching the sides, so you can glue it into place.

And then you're going to glue that rectangle of card that we cut earlier over that central support.

So if you're following the rectangular chassis, that will be 120 millimetres by 30 millimetres, glued onto that central support.

If you've got an alternative shape, then you will cut yours to size to cover that central support.

The correct glueing technique will make sure that the wood and the cardboard sections connect properly and stay stuck.

So you need to make sure you wipe off any excess glue on the edge of the pot 'cause we don't want to be putting too much glue onto our joints and our triangles.

Spread the glue evenly across the wood or the triangles that you are glueing , so that it's all covered in an equal, even manner.

And then remove any excess glue, so that you've just got a thin film of glue.

And that will make sure it won't move around too much if there's too much glue and it won't peel away if there's not enough glue.

So, now, we're going to strengthen that wooden frame to make sure that it's strong enough to support our electric vehicle when we add components later on.

So it might be a good idea to leave your frame to dry for a little bit before you start this next stage, just to make sure that it doesn't come apart when you start adding things onto it.

Once it's dry, you're going to place it on top of the A5 piece of card that we've cut to use for this step, and then you're going to mark out a rectangle that's 30 millimetres by 40 millimetres in one half of the frame.

So if you look at the image there, you can see, on one side of that frame, on the piece of A5 card, I've drawn accurately that rectangle.

We need to try and keep that measurement, even if you are doing an alternative chassis shape, because this is going to be important for a later stage of this model.

Then you're going to rule a line along the sides of the frame.

So where the frame sits, you're going to draw a line across the top and the bottom.

So you're using your frame as a ruler to mark the top and the bottom.

So it should be sitting central on that piece of card, so you've got an equal mark at the top and bottom.

So have a look at the image there, you can see the two lines that I've drawn.

Then you can remove the frame for the time being, so that it looks like this.

We've got two lines and a rectangle drawn on that piece of card.

Then you're going to very carefully cut out the rectangle.

So if you're using a thicker card, like this corrugated card here, that might be a little bit trickier.

You might need to get some help with that.

You may need to pierce through the cardboard first before you start cutting.

If you're using a thinner card, it might be a little bit easier to push your scissors into there, but again, it might be safer to use, pierce a hole first, to use that as a starting point for your cutting.

Now, we're going to secure the frame together.

So you're going to use a ruler to bend the card along those two lines that we marked.

So that top and bottom line that we've just drawn using the frame, you're going to use a ruler now to bend it up.

So you're going make sure both top and the bottom are bent upwards, so they're facing the same direction.

And then you're going to glue your wooden frame onto the cardboard template.

So you want to put glue on the base of the frame, so it sticks to the base of the card, and then glue on the sides of the frame, so that those pieces of card that you've bent using the ruler stick to the side of the frame like that.

So look at the image carefully, that's what it should look like, the frame and the base, and then those two side pieces of cardboard vertically stuck to the side of the frame.

And you need to leave that to dry completely now, before we do anything else to it.

Now, axles need to be parallel.

So the axles of your vehicle that we're going to be adding on need to be parallel in order for a vehicle to drive in a straight line.

So it's very important that axles don't look like this because axles that are not parallel, the wheels will not line up, the vehicle will not drive in a straight line.

When axles are parallel and they look like this, the wheels are in line, the vehicle can drive in a straight line.

So this is an important part of positioning the axles on our vehicle.

A quick check then, which of these pairs of wheels and axles are parallel, A, B, or C, which ones are parallel? Pause the video, and have a think.

Welcome back.

What did you think? Well done if you said, "B." Exactly, they are parallel, so the wheels are lined up in the same place, so that they can drive in a straight line.

Well done if you got that right.

So we're gonna make an axle holder to put our wheels onto our vehicle.

And we need to make sure it's accurate, so that our wheels and axles will be parallel, so that the vehicle will drive in a straight line.

So you're going to mark a position on the side of your frame.

So that cardboard that you bent up onto your frame earlier, you're going to mark two holes, where your axle is going to come through, and it needs to be 30 millimetres away from the edge, so that whether it's the front or the back, it needs to be 30 millimetres away from the edge and 10 millimetres away from the base.

So you're thinking about which way around your vehicle chassis will be.

The flat card will be on the top, and the frame will be underneath.

So you need to measure it 30 millimetres from the side and 10 millimetres from the base, so up from the bottom.

So you can see there on the image, showing you where to mark a dot.

And the same on the opposite side.

So you've got two places, two marks, where you can add your axles.

Then you're going to pierce those holes using a sharp pencil, and you're going to repeat it on the other side of the frame as well, so that you've got two holes on one side and two holes on the other side, and that's where the axle will be threaded through.

So it's very important that you're accurate with this measuring because, otherwise, your axles will not be parallel, and then the vehicle will not drive in a straight line.

A quick check then before we move on, why is it important to mark all the holes using the same measurements? So the measurements that I've included there, why is it important? Is it so the frame will stay attached? Is it so that it looks neat and tidy when you're finished, or is it so the wheels will be parallel? Pause the video, and have a think.

Welcome back.

What did you think? Well done if you said, "It's so the wheels are parallel." If we don't follow those same measurements on every side, then the wheels will not be parallel once we put them into place.

Well done if you got that right.

So that's your task then for the second part of the lesson.

First of all, you're going to follow the steps to assemble the wooden frame.

So you're gonna make sure that you attach the card supports using that neat glueing technique as well, and you need to leave that to dry.

Then you're going to follow the steps to mark those two lines and cut that rectangular hole into the A5 cards.

You've got those two tasks that you need to complete to get those components ready to assemble.

Pause the video while you complete that, and come back when you're done.

Welcome back.

How did you get on? So let's have a look at the next steps now, what we need to do with those two components that you've just made.

So you're going to follow the steps from the lesson, to fold that piece of A5 card and glue the wooden frame into place.

So go back and look at those steps of how to do that.

And then you're going to follow the steps to mark and pierce those four holes, two on each side of your frame, to make those axle holders, and make sure you are measuring accurately, so that your axles will be parallel when you're finished.

Pause the video while you complete those two steps, and come back when you're done.

Welcome back.

How did you get on? Well, you should now have a completed chassis that looks like this.

So that wooden frame that you've built should be glued inside that piece of A5 card.

And those folded upside should have those four holes that were accurately measured and pierced to make your axle holders.

And this is where the axles will be placed in the next part of our build.

It is the end of today's lesson, though.

I've had fun starting the process of building our prototype electric vehicles by completing our vehicle chassis.

We've learned that the chassis is the name for the vehicle's frame.

We've learned that axle holes need to be parallel to make sure that our vehicle wheels can operate in the right way and the vehicle can drive in a straight line.

We've learned that a wooden frame needs measuring and cutting accurately if it's going to be put together properly.

And that the wooden frame also needs to be joined with accuracy if we're going to make our vehicle chassis correctly.

Thank you for joining me for this lesson.

And I hope to see you for the next stage of this build, but it's goodbye for me for now.