Final model

STEP 1

First things first. Make sure you got your Snap option turned on in the status bar, and your OSnap enabled with some of the most commonly used options like End, Near, Point, Mid and Int.

We’ll start creating this little shovel from top viewport, like we would start tracing an image of some existing shovel imported in Rhinoceros.

With Curve command, create a curve in Top viewport which has its control points exactly like on the image below. This is why Snap (to grid) is handy tool to use here.

Image 1

Then we need another copy of this curve, and for that we will use Mirror command and mirror it across x axis.After that, use Join command to join two curves.

Then we can either use Line command to close these two curves into one closed polyline/polycurve, or use Close command which will do the same thing with less clicks.

Image 2

Now, using Rectangle command we will create a rectangle like on the image below: do not worry about the dimensions, just count the grid boxes and you’ll be fine. I’ve got some dimensions for you in case you get lost

Image 3

With Trim command, we will trim the parts of the two closed polylines which will help us join all curves into one closed:

Image 4

Next thing would be to make the corners smoother. They aren’t normally that sharp, are they? So, using Fillet command we need to fillet the upper and lower corners with 1 unit, and the inner ones with 2 units, and the tip of the shovel with 0.4 units:

Image 5

Now, before we go any further, it is good to check if all these lines and curves are joined all together. Just click anywhere on the line, and if everything is ok then it will be yellow as selected. One more thing to check is if this IS really closed curve with SelClosedCrv command which will select all closed curves.

Next thing we need is a basic shape of our shovel. Since it is curved in two sides, the best basic shape would be an ellipsoid. Using Ellipsoid command create one positioned just like on the image below:

Image 6

Ok, now we will Cut the Ellipsoid with the closed curve we created. From Top viewport, we need to select both Ellipsoid and closed curve, and run Project command. It is important to do this in Front viewport because the viewport is controlling the direction of the projection.

Image 7

Now we got two projected curves. One on the top and one on the bottom of ellipsoid. We don’t need the upper one, and we can delete it by selecting it and hitting Delete key on keyboard.

Using Split command, we will first select the object we want to cut which is in this case ellipsoid, and then the curve which is the object we wish to split with:

Image 8

Now we have finally created something that is actually resembling our shovel. This is one thin surface, and we need some thickness. Using OffsetSrf command we will first offset the surface and create one on top with distance of 0.3 units: (when you start the command, it will display white arrows on your surface, those are normals, and are used to see in which direction the offset will occur. Chances are your arrows point towards bottom, click on the surface and the arrows will change direction)

Image 9

We now have two flat surfaces and we need to connect them somehow. We’ll do that with BlendSrf command which will basically create nice blend surface between two surfaces: (Use AutoConnect option in command line)

Image 10

With Join command join the blend surface with two flat surfaces. You will notice on the part where would handle start there is some weird hole. Never mind that, that part will soon disappear.

Again, we need to create another Ellipsoid. Using Ellipsoid command create one like on the image below. Again, the positioning and size is crucial here.

Image 11

Hint: When you start Ellipsoid command, just follow these steps. Input “10, -3.75″ (that will set the center in the right position), press enter while active Front viewport (click anywhere in the viewport), “6, -3.75″ (that will set one dimension of the ellipsoid – length), press enter while still in Front viewport, “10, -2.25″, press enter while in Front viewport, “10,-1.5″ press enter Top viewport is active. Do not input apostrophe signs.

Using ExtractIsoCurve command, create a extract isocurve from the middle of ellipsoid. You need to hit the Quad point to make sure the circle is in ellipsoid’s center.

Image 12

Using ExtrudeCrv command we will create a cylinder out of this circle. So, start the command, select the circle, make sure the Cap option is set to Yes, and input 15 units in command line as extrusion distance.

Image 13

With BooleanUnion command connect ellipsoid with cylinder:

Image 14

Again, with BooleanUnion command we need to connect the plate and handle part:

Image 15

If you are getting something like on the image below….

Image 16

… then you need to use Dir command on the plate before you use BooleanUnion. Because the normals are pointing towards the inside, while they should point towards outside.

This next part will be a bit tricky, so pay attention. We need to create a variable fillet on the edges that connect the handle part and the shovel plate. The biggest radius will be 1 unit, while all others will be 0.8 units.

So, start FilletEdge command, and set 0.08 as default radius. Select the edges:

Image 17

… press enter, and click on AddHandle option in command line. Add 7 more handles like on the image below:

Image 18

The two big ones show be set to 1 unit, and you do that by clicking on the outer dot (center of an arc) and inputing the values.

Image 19

Final scene

Since it that time in the year again, some of you might find it useful to learn how to create few Christmas decorations for your tree visualisations

Introduction

Well, basically what we will do here is use solids for basic shapes and cut them how we like it.Simple, eh?

Step 1

In this step we will be creating the simplest decoration.

First Decoration

Go ahead, and create a sphere using Sphere command. Center it in the origin (0,0) and use 10 units as radius. To make this even simpler, you can set your Grid options like I have them. Just run Grid command, and where it says Extents click on it and input 10. That way you will have 10 units in your grid in every direction in the viewport which was active when you run the command. To apply this setting to all viewports, just use ApplyTo setting in Grid command. Click on it so it toggles from ActiveViewport to AllViewports. Now, simply using Snap option in your status bar we will start creating this Sphere.

Image 1

Once you got your Sphere, create another one, using 7 units as radius and position its center on 8,0. That is, 8 on the x axis, and 0 on the y axis.

Image 2

Now, using BooleanDifference make a hole in the bigger Sphere.

Image 3

We need to fillet the edges of this sphere. Using FilletEdge command fillet the edge with 0.2 as radius.

Image 4

Create a Circle from Top viewport with 5.5 as radius.

Image 5

We will Project this Circle onto the Sphere. We need to do this from Top viewport. So make sure it is active, and run the Project command to do the projection of the Circle on the Sphere. You will get 3 projected curves, and we only need the top one, so you can delete other two:

Image 6

Using Split or Trim command, we need to trim the upper part of the Sphere, with projected circle.

Image 7

Next thing we need is another Circle. This time create a Circle with 1.5 units as radius. Create it from top viewport in the origin (0,0). Then you will need to move it up (from either front or right viewport) with Move command by 17 units.

Image 8

Now, using ExtrudeCrv extrude this circle up by 1 unit. Make sure you don’t have Cap set to Yes, or BothSides set to Yes. Those two options need to be set to No.

Image 9

Ok, once you’ve done this, you need to make a surface with smooth transition from the sphere to the extruded circle. You will use BlendSrf command to do just that. As for the BlendSrf options, just leave it at default settings. Meaning AutoChain set to No, and for the Blend Bulge leave it as well at default settings, which are 1,1 and all other options unchecked.

Image 10

Next we will create a cap and a little wire to hang our decoration somewhere. So, using OffsetSrf offset the little cylinder surface outwards by 0.1 units.

Image 11

Now, using ExtendSrf command we will extend the upper edge of the offset surface up by 0.1

Image 12

Using Cap command we will close this surface into solid.

Image 13

Create another Circle, from Top viewport and use 0.5 units as radius. You should get your circle like on the image below:

Image 14

Now, using ExtrudeCrv command set the Cap setting to Yes, and extrude it up by 20 units, just so it goes through the cap:

Image 15

Using BooleanDifference command make a hole with this cylinder in the cap:

Image 16

Using FilletEdge fillet the edges of the tip with 0.1 as radius:

Image 17

Create another Circle with 2 units as radius, and position it like on the image below. Just make sure you create your circle from Front viewport. You can start Circle command, input in the command line when it asks you for the center 0,20 for the center, and then just 2 for the radius. You should get exactly the curve like on the image:

Image 18

We need a Curve starting from the circle. Using InterpCrv command we will create such curve from Front viewport: (you can start using OSnap if you haven’t already – Near would come in handy here)

Image 19

Using Mirror command we need to mirror this curve to the other side.

Image 20

Using Trim command we need to trim the Circle:

Image 21

I have almost perfectly hit the curve direction and smoothness and actually the curve is visually tangent to the circle. In reality that isn’t the case, so we need to fix it. We will match our curve onto the circle with Match command:

Image 22

Here you can see the black curve on the left, this is how the curve will be adjusted to match the tangency. So, now you see I didn’t actually hit the tangency manually. Do this same step for the right curve as well, and join all three into one:

Image 23

If necessary, using PointsOn you can change your curve a bit. But you will see if this is necessary after you make a surface. Using Pipe command we need to create a pipe surface. Use 0.2 as radius:

Image 24

Here you see this needs some adjustments. So, first, try moving it up a bit to see if this can fix it. If not, using PointsOn you will need to adjust the curve itself.

Image 25

For the purposes of this course, just moving this wire will do.