Discover how to build a lower arm for a lamp using a step-by-step method. This article guides you through creating new components, building sketches, dimensioning and constraining sketches, modeling and copying components, among others.
Key Insights
- The tutorial begins by creating a new component named "Lower Arm" and then proceeds to build a sketch on the same face used in the previous creation of a hole.
- After the sketch is complete, the dimensions and constraints are added, a horizontal vertical constraint is placed to keep the geometry from moving side to side. The resulting project geometry is either purple (projected) or black (fully dimensioned and constrained).
- Lastly, the arm is modeled by extruding the sketch and the whole process is repeated to create a second arm on the opposite side of the lamp. This is done by copying and pasting the existing component and moving it along the X-axis.
In this video, we will build the lower arm for our lamp. I will go to my data panel and open step 02, lower arm.
Remember, you can open with a double click or right click open. When my file is open, I will close my data panel, and we can begin to build our lower arm. The first thing we need to do is create a new component.
Again, I can go to the New Component button here or right click on this component, New Component, and that will make a new component nested inside. I will double click on my name and rename it Lower Arm. Enter.
You will notice that all of the objects in my base component have become grayed out, and this is because they are not in the active component. So let's build our first sketch. With Lower Arm 1 active, I will create a sketch, and I will choose the same face which I chose earlier to create my hole.
My view will reorient to this view, and let's create a rectangle. My arm will go somewhere like this, so I'll draw it roughly to shape. Next, we know that there will be a second hole here, but instead of drawing a new point and creating a separate hole command, we will build our hole using the extrude.
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So I will go Sketch, Circle, Center Diameter, and I will draw my circle here, and again, I will not worry about the dimensions. I will make my dimensions in a minute. The last circle we need is the circle that will go on top of this object.
Because we are building our geometry in location and in place, we can use projected geometry. If I go to Sketch, Project Include, Project, which is the keyboard shortcut P on your keyboard, you will see this project window appear. I can select specific entities or entire bodies.
I will select specific entities and zoom in and select this circle. It may be hard to see on your screen, but you will notice that that circle has now become a dark purple color. This means that that sketch geometry is now present in my current sketch and is non-editable because it is projected directly from my 3D geometry.
I will hit OK, and now we can begin to dimension and constrain our sketch. First, I will go D for dimension, select my circle, and let's make this five, Enter. Next, my rectangle will be 30 millimeters wide.
And 285 tall. If your geometry is moved, that's okay. Click and drag on your geometry to move it back into approximately the right location.
Next, let's dimension our circles to the edges of our rectangle. I will zoom in, select the center of this circle and this endpoint, and I will make this 20, Enter. And I will do it to the top, 20, Enter.
Notice that my geometry can still move side to side. So instead of dimensioning this geometry, I will place a horizontal vertical constraint. If I zoom in here with nothing selected, I will select my horizontal vertical constraint.
When I hover over this circle and click the center, you can see that I want to snap to the midpoint of this line, but I can only select the endpoints. By holding down Shift on my keyboard, I can open up my O snaps. As I hover over the midpoint of my line, you will see the midpoint snap appear.
By clicking with Shift being held down, I can snap a horizontal vertical constraint from the midpoint of this line to the center of that circle. Let's do that one more time for the circle at the top of our arm. I will select horizontal vertical, select the center of my circle, and holding Shift, I will select the midpoint of this line.
You can see that my geometry is either purple as it is projected, or black, which means it is fully dimensioned and constrained. We can now hit Stop Sketch, go to our Home view, and go to Extrude. Notice that when I hover over this rectangle, the bottom portion is not selected.
This is because my projected geometry has split this face and this profile into two separate sections. I will need to click once here and here to select my full rectangular face. I can now drag out 15, Enter, and we will see that the arm with the holes already cut out has been modeled.
I am done modeling in this component, so I will activate my main component. And to finish this video, I would like to create a second arm on this side of my lamp. We can do this by simply copying and pasting our existing component.
If I go to my lower arm component, right-click Copy, I can hit right-click Paste, and it will paste a copy of my component directly on top of my old component. When it has pasted, the Move command automatically opens. In the Move command, I can use my sliders to move my object along three directions, use my Rotate to rotate my object about my axes, and use these square grips to move along two axes or a plane.
I will hit Cancel and delete my old component, and again go right-click Paste. I will now slide along my X-axis, negative 45, and that will place my other arm directly opposite my first arm. I will go to my Home view and save my file.
Again, feel free to write whatever description you would like. I will leave this as User Saved and hit OK. In the next video, we will build the upper arm and create an assembly component.
I will see you in the next video.
