By the end of this video, you’ll know how to use the ellipse command in Fusion 360.
The ellipse command can be activated from the sketch dropdown list or from the right-click sketch menu.
Once activated you’ll have to The selection mode controls how objects are select when you drag in the canvas. More an origin plane or the face of some preexisting geometry. For this demo, I’ll simply select the XY origin plane.
You’ll notice after selecting a plane, Fusion 360 went ahead and automatically oriented the view to look straight at the sketch. If yours didn’t do this, or if you’d like to turn it on or off, then you can change this in your preferences menu.
Select your username in the upper righthand corner, and select preferences from the drop-down list.
In the preferences dialog, you’ll have to select the design tab. From there you will see the option about midway through the list that says “auto Re-arranges screen to look at selected object. More sketch.” If this is turned on, as mine currently is, then your sketch will auto-rotate to look directly at it.
If you decide you don’t want Fusion 360 to auto-rotate at the sketch, then you can uncheck this selection, click the apply button, and then the okay button to close the dialog Creates a solid box. Select a plane, draw a rectangle then specify the height of the box. More.
With the ellipse command still active, I’ll click on the center origin and drag out with my mouse. The ellipse command requires us to define the center Creates a sketch point. More, the major axis, and another point of the ellipse.
You’ll see the first input field is the length of the major axis or the longest side of the ellipse. I’ll type out 100mm and hit the tab key to lock the dimension in place.
Next, you’ll see that we have the choice to either type out a degree for the ellipse to be set at, or we can always click to reference the grid or other preexisting sketch geometry. I’ll simply click on the horizontal (keyboard shortcut “L”) Creates lines and arcs. Select a start and endpoint to define a line segment. Click and drag the endpoint of a segment to define an arc. More to snap the ellipse to it.
Lastly, the ellipse tool requires us to define another point or the width of the ellipse. Watch carefully as I slide my mouse cursor along the path of the ellipse. You’ll notice that I don’t have to click directly at the ellipses midpoint. If I were wanting to snap this ellipse into preexisting sketch geometry then I could click anywhere, and the width of the ellipse would snap into place.
Alternatively, I could just type out a dimension for the width. I’ll type out 50mm, followed by the tab key to lock the dimension in place. Then, I’ll click to set the ellipse.
After placing the ellipse we’ll see that we have a closed profile shape, which is signified by this orange background highlight.
You’ll also notice that because we drew the ellipse starting with the center origin point, and defined both the width and the height, we now have a fully constrained sketch.
There are two ways that you can confirm you have a fully constrained sketch. First, all of your sketch geometry should have black lines, which mean that the lines can’t be moved. If the lines are blue, then they can still be moved in some sort of direction. On top of that, you can always select the geometry and try to move it around… which can be helpful if you can’t figure out why a sketch still has blue lines.
The second thing to check is the sketch icon in the Fusion 360 The browser lists objects in your design (everything from planes and sketches to parts and assemblies). Use the browser to make changes to objects and control visibility of objects. More. If I toggle open Sketch folder in the Fusion 360 browser and take a look at this sketch, you’ll notice something different than when we first started. The sketch icon, just to the left of the name, now includes a red thumbtack icon. This red thumbtack signifies that sketch is fully constrained, which is a good thing.
This means that the only way to alter this ellipse is by double-clicking on the dimension fields to edit their dimensions… ensuring that we don’t accidentally move or alter the sketch when we update any other part of the model.
In summary, Fusion 360 offers only one type of ellipse command. The ellipse command requires you to define the center point, distance of the major axis, and a third point which defines the width of the ellipse.