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- View Offline
- Adding and removing from selections
- Stretching elements
- Creating mirrored copies
- Leveraging grips
- Editing hatch patterns
- Using layers to organize a drawing
- Changing layer states
- Understanding the BYLAYER property
- Taking measurements
- Automating calculations with the Quick Calculator
- Constructing a multi-view part
Skill Level Beginner
One way to avoid errors is to always use a calculator to solve equations. Fortunately, AutoCAD has a fully functional built-in calculator that may just replace the one you have on your desk. In this lesson we are going to explore the Quick Calculator tool. On my screen I have a polygon, let's see if we can re-create this shape. To do that I'll move up to the Draw panel and launch the Polygon command. I will then enter 6 for the number of sides. I'll click over here on the right side of the screen for my center point.
Since this is dimensioned from face to face, this must be a circumscribed polygon. Now what's the radius of this circle? Well, the diameter is 8.78, so the radius must be half of that. Instead of trying to calculate that value in my head, when AutoCAD asks me for the radius of the circle, I'm going to press Ctrl+8. This brings up the Quick Calculator tool. This calculator works a lot like your Windows calculator, except it will apply the value to the active command; we can see that right here.
Now when the calculator opens, it opens up in a reduced state. I am going to click the More button to get access to the Number Pad. Down here I'm going to type 8.78/2. Note you can also use the keys on your keyboard. I will then click equals and then Apply. This moves the value down to the Command Line where I can press Enter to accept it and finish the polygon. Anytime AutoCAD asks you for a number, you can press Ctrl+8 to bring up the calculator if necessary.
Let's pan the drawing over, and we'll expand on this concept. In this case, let's say I'd like to offset this green entity, the same distance that these two endpoints are apart. I'll start by launching the offset command. Now what's the distance? I'm not sure, I am going to press Ctrl+8. Let me take a second and mention that there is a lot of functionality on this dialog box, more than we have a chance to talk about in this lesson. If you have a question about any of the tools that you see in this dialog box, click the Help icon to access AutoCAD's help feature.
I'm going to click this icon in the middle; this allows me to extract the distance between two points. I will then click this endpoint and this one. There is the extracted value, I'll come down and click Apply to move that value to the Command Line where I will press Enter to accept it. I will then select my segment and offset this upward. When I am finished, I'll press Escape. Let's take this idea a little further. Maybe I'd like to create a center line, now I have to offset this geometry half the distance.
I'll launch Offset, what's my distance? Ctrl+8, take a look at this area up here, this is our history. Not only does AutoCAD maintain a history of our equations, it also remembers the solutions. If you double-click on any of these values you can move it down to the expression area. I am going to double- click on the last solution. I'll type /2 and I'll click equals. I will then click Apply, Enter, I'll click my line segment and I'll offset it upward, when I am finished I'll press Escape.
If you look around, you'll find the calculator in many places in AutoCAD's interface. For example, I'm going to select this polyline and then I'll come over to the Properties palette and I'll drag this down such that we can see the Geometry area. Notice all of these numeric values, the Area is probably the most valuable. If I click in this field, notice that we get access to the calculator. In fact, if I click in any field with a numeric value I can access the calculator.
Just for a second let's say that this area represents square feet, and I'd like to convert this to square meters. To do that I'll click the calculator, I will then click to collapse the Number Pad and I'll expand Units Conversion. Currently the Value to convert is 0, rather than copying and pasting this number down, I'm going to click in the expression field and then I'll click in Value to convert, to move that number. Units type; I'll expand the menu and choose Area, Convert from, I'll select Square feet.
Convert to is set to Square meters. We can see that this polyline is just over 4 square meters. So not only will this calculator will do expressions, it also allows us to calculate units conversion. One other place where this tool comes in handy is computing architectural measurements. I am going to open another drawing; I'll grab this drawing called archCalc and click Open. This drawing is setup using standard architectural units. In fact, we can see the fractional inches down here in the coordinates area.
I'm going to press Ctrl+8 to access the calculator. The calculator is also a stand-alone Command. Now that it's open, let's add two fractional measurements. I am going to type 8'3-1/16". We'll type the values just like we enter them when we're drawing the geometry. Here's the trick, two spaces and then the operator and then two spaces before we enter the next number. I'll add this to 5' 2-7/8".
And when I press Enter, you can see AutoCAD makes quick work of that calculation. Now that we have a pretty good idea of how to use the Quick Calculator, let's try and use it in a practical example. I am going to close the palette, let's say I'd like to find the volume of this room in cubic feet. I'll start by coming over the Utilities panel and I'll open up the Measure menu and I'll choose Volume. Calculating a volume is just like calculating an area. We are going to work our way around the room.
When I'm finished, I'll press Enter, now I can apply a height. Let's say this is a 9' ceiling, I'll type 9 and then the apostrophe and I'll press Enter. And we can see the Volume of the room in cubic inches. Now I wanted cubic feet, so I'm going to come down here and click Exit. I will then press F2. This shows me the history of what's been passing through my Command Line. Here is the value we just found, I'm going to select this; I'll right-click and copy it to the Clipboard.
I will then close the dialog box, I'll press Ctrl+8 to access the Calculator, I'll click the More than button such that we can see the rest of the tools, and I'll drag this out a little bit. For the value to convert, I will drag across the 0 and then I'll right-click and paste my value. Units type Volume, Convert from Cubic inches, Convert to Cubic feet, and we can see this room measures just over 2790 cubic feet.
So the next time you have to calculate some values, don't reach for the handheld calculator, instead press Ctrl+8, and let AutoCAD solve all your problems.