The Geneva cam assembly project is started. The Project #3 file is used as a starting file. The naming scheme for the assembly is explained. The first part, the cam, is drawn through the creation of the cylinder feature, hole, and keyway.
- [Instructor] Welcome back, this is our first demonstration for the Geneva Cam assembly. So we're going to start with our project three complete file and I'll do a save as. So we're going to save this in our chapter five folder. It's going to be called project number four. And we're going to add a dash to this because each of our different parts have to have a unique file name when we do our reference to assembly. So this first part is the cam so we're going to call this 4-1 and then underscore 05, underscore 01.
And we're saving this in our chapter five folder. And let's go ahead and delete the original solid. And we're going to concentrate on the 3D for this initial part of these files and then we'll come back and do the 2D drafting after that, so let's take a quick look at our PDF of the completed version before we jump into doing the three-dimensional solid. I'll kind of explain the process. This is the cam and drive wheel drawing. We're going to be using this for our dimensions to draw the cam part.
So this is a sub-assembly showing the cam and the drive wheel assembled together and then we have a detail view off to the side to show detail of this key way and key seat. Or key way I should say with this raised portion. And then later on we'll create a 2D drawing where we reference the drive wheel and the cam together to create a dimension drawing. So I'll be referencing the dimensions for the cam for this first drawing and we'll be using the polar array or polar feature array to create this part.
It'll actually go very quickly, I think. And then we'll go into the drive wheel, and then on the next PDF file, this is your base and pin drawing and then the shaft and key drawing. These will be separate parts. So after we finish up the cam and the drive wheel, we'll do 3D versions of the base and pin together and then we'll do a separate three-dimensional file of the shaft and key. After we finish up all the three-dimensional parts then we'll create a three-dimensional assembly and use that to generate a 2D assembly drawing of our geneva cam.
So let's go ahead and start with the cam drawing first. So we're going to be drawing this in the top view, that's the orientation of the part, so I'm going to maximize my view number one top and then we're going to go ahead and start by drawing the profile of one portion of the cam assembly. We can do this a number of ways so you could draw the part as a primitive cylinder and then create cuts or you could draw the profile. And actually, let's do it that way.
Let's go ahead and draw this as a primitive shape first. So I'm going to start in feature modeling. I'm going to go to my cylinder feature tool and I'm going to set my radius and height. So the radius will be one half of the outside diameter of the part which is 4.802. So I can just type this in as 4.802 and then do a /2 to divide into half. And then for the thickness or the height, we'll use .2 inches. So now here's the axis of the part.
So I'm just going to click here and then let's switch back over into our tiled view orientation so you can kind of see how this works. So let's go ahead and draw this so it's oriented to the top view so our circular view is in the top and then we clicked our second point in the front. So you just want to make sure this is oriented to the top view. Then we can go ahead and add in our cut feature but let's first do our cylinder feature and the inside. So I'm going to go to my cylinder tool once again.
I can work in view two for this one. So this time I'm going to set this for the smaller radius which has a diameter of one. So my radius is .5 and then the height of this will be a total height of .525. Then I'll go ahead and snap to the center of the top of the cylinder and then we want my axis here to be design Z.
So this forces this to be oriented so it's in the same axis as the outside cylinder. So now let's rotate the view. So you can see here I've got the cylinder placed up at the top of the cylinder and the largest cylinder are aligned with one another. But we have a slight offset here. So what we need to do is figure out how far up to go. So we have a total distance of .525 so we need to subtract that from .463, which is the dimensions of .2 and .263.
So that gives us a difference of .062. So what we're going to do next then is raise this cylinder up, we want to make sure we're in the front orientation here and we're going to come up .062. So that gives us the proper offset. So when I did that, I wanted to make sure that when I moved this, I wanted to make sure I was in the front orientation. So let me just undo this and try this one more time. I'll show you how to do this one more time.
So I'm going to pick the cylinder first and I'm going to go to my move command. I can just click out an open space and I want to make sure that my AccuDraw is oriented to the front view so I'll hit F and I also want to hit the spacebar so I'm in XYZ. So now this is forcing the movement to be along the Z. In fact, I can even hit the enter key so that it doesn't accidentally move right or left. So I'm going to come up by .062.
There we are. And then before I draw the hole through this, I'm going to union this together. So I'm going to go ahead and create a union. So this is in feature modeling. Union feature. And I'll go ahead and make these two cylinders into one solid. So now what we need to do is create a hole down the middle of the part that has a diameter of .5. So we'll set the hole type to simple, drill through, diameter is .5, then I'll just click anywhere on the solid, then I'm going to drag over to the center.
To confirm I'm on center I'm going to use center snap and just snap to the edge of this upper circular area and there we have it. Let's switch over to the top view orientation now. In fact I'm going to tile my views here. Makes it a little bit easier to draw here when we can see this in wire frame. So what we need to do next is create a cut for the key way. The width of the key way is .125 inches. And then the depth into the part, we just want to make sure that we overlap the edge of the top of the circle.
So what I'm going to do I'll use my origin set to the center of the circle. So I'm going to go to my place block command and then I'll hit F11 and origin. So now we want to offset the cut .0625. There we are. And then we're going to come up and over. So along the Y axis I'll just set this to .6 from the bottom edge of the arc. So what I'll need to do now is I need to move this down and then I'm going to come up .6 so that gives me the correct distance coming up, and then I'm going to come over a total of .0625 again.
So now what this does is it gives me a distance from one corner to the other. Let's just use our measure tool to measure this. So I should have a distance of .125, which I do. So we started by offsetting here .0625 and then over another .0625 from the center, and that gave us the correct shape for the key way. So now let's switch back over to view number two. I'm going to rotate this slightly so we can see this in a more isometric view.
So now this is a shape for our cut. There, that's a little bit better. I turned off default lighting for this so we can see this more clearly. And then let's go ahead and use our create cut tool, or cut feature, and then we're going to go one direction all faces, and we're going down into the part, and that creates our cut feature for the key way. For the next step what we need to do is create the arrayed feature.
So we'll come back and do the array in the next part.
- Navigating the interface efficiently
- Creating 2D views from 3D solid geometry
- Creating a complex shape
- Creating dimension styles
- Creating a 2D view with title blocks
- Dimensioning and printing a drawing
- Beginning the 3D solid
- Drawing and dimensioning a plate, bracket, and more