Bodies and patterns, part 1

00:00

Welcome to part two of creating the wheel video series. In this video, we'll talk about bodies and patterns. Part one of the wheel series showed us how to sketch and revolve this half of a wheel. We have a hole in the middle because the sketch was offset from the center line. Let's start by opening a sketch on the left plane. Next, I'll add a couple of circles and some reference lines.

00:37

One is from the center of the wheel to the center of the large hole, and one is to the center of the small hole. Anchor the end points of these lines to the center. Make sure that the vertical line is vertical. And then we can make sure that both lines are construction and fill in this angle as 36 degrees.

01:04

Now you see they overlap a little because we've sketched approximately. So let's change some of the values here. This value I'm going to change to three inches. That's the distance from the center. I'll also make this hole a one inch diameter. Give the big hole bigger diameter. So we'll call this five.

01:30

and from the center we'll give it a distance of six inches. That should be enough.

01:38

Now we want to extrude these shapes as a cutout through the wheel. And we also want to add some draft as we're doing it. So let's select inside the circle, shift select inside the second circle, set the draft in this case to five degrees.

02:01

and just drag the arrow so it goes straight through the wheel. Now one thing you might notice is that the five degree draft went the wrong way. Notice the hole is getting smaller. So there are a couple of ways to fix this, but the easiest way is to go to the history tree, look at the extrude that we just created, and you can see the draft angle will allow you to key in a negative five from here. And notice now that the draft is going

02:32

The next thing we want to do is to create a pattern. But the pattern is under transform. You can pattern bodies. You can also pattern sketches, but you can't pattern features. So what this means is that we have to change the way we've treated this cutout. If you're going to make an individual cutout, that's fine. But if you're going to pattern it, you need to change the combined type from subtract to new body.

03:03

All right, so now instead of cutting a hole in the wheel, we've made two new bodies. We're going to come back later and subtract these bodies from the wheel. But in order to get the pattern, we had to create these holes as bodies. To make this pattern, let's go to the transform and pattern. Pattern will allow you to make a linear or a circular pattern. In this case, we want to make a circular pattern.

03:32

and the prompt is telling us to select bodies or sketches to create a pattern. Notice that it doesn't say features. So we're going to select the bodies from the items list. It's tempting to want to select them from the graphics window, but don't do that. We'll select these two bodies, grab the center indicator and drag it onto the axis for the wheel. Make sure it goes around that.

04:02

Now this dotted circle only means that it's going to pattern in the indicated direction. So notice that the curved arrow is showing how this selection is going to be patterned. And that's not correct for what we're trying to do. What we want to do is going to use this curved arrow and notice that when that gets highlighted, the dotted circle moves. Now we can click and drag.

04:31

I'm just going to leave this as some arbitrary point and change all of the values. The first thing I want to look at is rotated. In this case, we have a selection of two separate bodies, these two blue bodies. And so we use the rotated option. If we use uniform, then notice the relationship between those two bodies stays the same. And that relationship would then be patterned.

05:00

So that's not at all what we want. We want to pattern both of them rotated to keep all of the holes around the same center. Next, I want to select this to make it five and I want to change the spacing to 72. Now that's correct and we're going to hit Done.