Just Type The Number
I think this post is more about me and the way my brain works than it is about learning to use SketchUp. Now that I’ve become somewhat adept at modelling, I really admire the simple and elegant way this program works. But it wasn’t that way at the beginning, there were several elements of the program that took me a long time to catch on to, and one of them was entering dimensions. It turns out that this is so simple, I flew right by it and couldn’t get it to work because I was expecting more complication.
I’ve been told that I could complicate a peanut butter and jelly sandwich, and I’ll admit that sometimes this is true. But I have also been influenced by bitter experience using software that was written by guys like me, programs with convoluted methods to do the simplest tasks. The good folks who made SketchUp did a wonderful job at keeping things simple. And simple is good when there is a lot of work to do. If you’re like me, sometimes it takes a lot of work to understand simple.
Down in the lower right corner of the modeling window of SketchUp is a small window labelled “Measurements”. Depending on what you’re doing, the label may say “Length”, “Dimensions” or “Distance” and when you’re drawing, moving or extruding something, the numbers displayed in the window tell you how far you’re going. You might think (as I did) and then try repeatedly (as I did) to wiggle the mouse and then click when you see the number you want. That will work, but you will spend most of your time bouncing back and forth between just a little over and just a little under what you want. Frustrated with that, I read the directions (reluctantly) and found something to the effect of “type the dimension in the measurements window”. Taking that literally, I desperately tried to click the cursor in the little window before typing. That doesn’t work. No matter how many times you try, or how loud you cuss.
Here is what does work:
Start the command, click on a starting point and let go of the mouse button. Move the cursor in the direction you want to go and when you see the colored inference that lets you know you’re moving in an axis direction, let go of the mouse. Now, type the number and hit the Enter key. You don’t type the number in the Measurements window, you type the number and it appears in the Measurements window.When you catch on, this is as quick and easy as it gets.
When you type, the distances will be in the units that you choose in the Model Info window. If you’re working in inches, you can enter fractions as decimals, or two numbers separated by a forward slash, 1/4 for example is the same a .25. If it’s a mixed number, hit the space bar after the whole number. SketchUp will read improper fractions and if you forget the space the program will read 1313/16 as one-thousand-three hundred and thirteen sixteenths, and not thirteen and thirteen sixteenths. If you want to switch between units in midstream you can do that by typing a dimension indicator after a number. If you’re making cabinets for example, and using European hardware, you can copy holes 32mm apart just by typing.
When you’re moving or copying, or extruding with Push/Pull the distance you type is the distance the object moves. If a box is four inches high, and you want to make it eight inches high, you start the Push/Pull command and type the number 4. Sorry, but sometimes you do need to add and subtract. 
Another cool way typing dimensions works is with the rectangle tool. Type two numbers separated by a comma and hit Enter. You can also pick up a point inference from something existing and use that for one of the numbers. If the inference is for the first number, type “,X” or if it’s the other way around type “X,” and hit Enter.
The big lesson for me when I picked up on this was that if something is a complicated struggle to accomplish in SketchUp, the chances are very good that I’m struggling with complications I’ve thrown in. Look for the simplest way to do any task, this is supposed to be fun, and it really is easy.
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This is number 5 in a series of 10 posts. You can read the whole series if you click here.
Hey Bob, great post!
I find myself using the dimension box for every move I make in Sketchup. (I think it’s called the “VCB” for “Value control Box”) But it’s a great way for me to make sure I’m going to where I want to be. Like sometimes, even if I can drag out and snap to the dimension I want, I sometimes move the mouse accidentally as I click and end up missing my mark.
The other thing I found myself doing was starting the action, going to type the dimension into my keyboard, then accidentally hitting my mouse which causes the numbers to reset. So now, I start AND finish my action, then I correct the dimensions by typing them in directly after completing the action.
Great post!
Matt’s comment is a great addition to the post. I have always entered dimensions but never realized I could enter them after finishing the box or line or… One thing that I have found useful is that sometimes it is easier to perform your action in the opposite direction and then enter a negative value to make it go the direction you want it to go.
One thing I noticed is even though I entered my dimensions in the VCB, lets say for a line length
of 6ft. and regardless of axes. A small rectangle will appear in the model as if it were a “tool tip” next to the cursor arrow. That dimension is never exactly what you had typed into the VCB to start the line?? Causing me to question myself, so like in Matt`s post. When you click to finish the line or set your end point. Then add the dimension, you know your spot on and it does help you concentrate and develop a work flow. Especially as a newbie, being I was ( still!!) second guesting myself and not not feeling that sure or confident. Taking my eye off the model in addition to searching for a tool, instead of using short cuts // hot keys. You waste time and add to your frustration in learning.
The popup tag can be confusing. If you click the mouse when it is visible, the line will snap to that dimension. But it is reading where the cursor is, not showing what you type in the measurements window.