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Let’s try to model this nice little garden shovel. This tutorial is suitable for beginners and is very simple to follow.
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.
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.
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
With Trim command, we will trim the parts of the two closed polylines which will help us join all curves into one closed:
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:
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:
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.
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:
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)
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)
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.
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.
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.
With BooleanUnion command connect ellipsoid with cylinder:
Again, with BooleanUnion command we need to connect the plate and handle part:
If you are getting something like on the image below….
… 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:
… press enter, and click on AddHandle option in command line. Add 7 more handles like on the image below:
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.
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