- The Rear triangle is now almost complete.
And the final things that we're going to add
are two small bridges between the Seat Stays
and the Chain Stays like almost everything in cycling
not every frame has these.
And there's a bit of a debate about whether
they're actually needed for stiffening
the frame or whether they're just there
for mounting things on like mud guards or fenders.
In this model, I'm going to go a bit more
traditional and add them in. But if you prefer,
you can leave them off.
Open the Assembly and let's insert a new part
by going to Assembly, Insert Components, New Part.
And as usual, depending on your settings
at this point you might be prompted to
enter a file name and if so call this first part
Seat Stay Bridge and then we're back in the Assembly
and we can choose the Plane to start this part.
So I'm going to select the Right Plane of the Assembly.
You can select it here on the left.
And now this is an extremely simple part.
It's just one single feature, a single tube.
For the position it needs to be somewhere along this line.
So let's get the circle tool, draw a circle
roughly in the right position.
And then you probably have to select the center point
of the circle and then hold down Control
and also select the line and then add a Coincident Relation.
Then let's add a second circle
have the same center point and lets add some dimensions.
So it was 10 millimeters diameter.
It's the smallest tube that we've used
and let's drag in that second circle so it's smaller.
And the wall thickness is 0.9 millimeters.
Then we can set any position along this line.
So I'm going to get the Smart Dimension tool.
I'm going to select the end
of the line and the middle of the circle.
And I'm going to set it as 130.
Then we just need to extrude this profile out to the side.
So I'm going to go to Features,
Extruded Boss Base going to go Up To Surface
and just choose that Seat Stay part like that.
Then let's do the same on the other side.
So enable Direction 2 and then
let's also choose Up To Surface
and then choose the one on this side and then press OK.
And that's all there is to it,
So we can exit editing that part
by clicking up here in the top right.
Some people say that these bridges
are really important for bracing the frame.
Some other people say that they don't make any difference.
So at this stage, if you need to, you can rename the part
by right clicking on it and pressing Rename.
And let's call that one Seat Stay Bridge
and you can save the assembly
and we can save that part externally.
Now we're going to add a similar one down here
for the Chain Stay using the same process.
So let's go to Assembly, Insert Components, New Part.
And then again, if needed write in your new file name.
Call this one Chain Stay Bridge.
if not, let's choose the Plane.
So again, it's the Right Plane and let's draw a circle
and this one should be somewhere along this line.
So let's draw it in roughly the right place
and get the center point.
Also select that line and then add a Coincident Relation.
And then get another circle, and then add that inside.
The size is the same as the one that we just made.
So it's 10 millimeters diameter.
And then the wall thickness, just drag it in like that.
And the wall thickness is the same as well.
So it's 0.9 millimeters.
- For the position of this one
I'm going to get the end point of the line there.
And I'm going to set this one as 75 away.
So at 75 millimeters, and that
should fully define the sketch.
And then we can go to Features,
Extruded Boss Base and we can do
Up To Surface select that Chain Stay
and then do the same in the other direction.
So select Direction 2, select Up To Surface
and then select that Chain Stay on that side.
Press OK and now this part is created.
So we can exit editing that part,
We can right click on it and rename if you need to.
So I'm going to call this one Chain Stay Bridge.
So this one down here, it braces the rear frame here
and it can also be useful for adding a kickstand.
So now if we zoom out the frames looking great
and we can start adding some more
smaller details in the next chapter.
At this point, you can save your assembly
and then save that new part externally if you need to.
if you want to check your assembly
against the exercise files at this point
then the files from the starting point
of the next chapter, Chapter 4 are the same as
the end point that we're at right now.