It seems like a vast majority of the woodworking blogs I read make their plans available by PDF and SKP files. Most people know what a PDF is these days, but what’s SKP? It belongs to a program called Sketchup, which Google originally owned, and sold to Trimble in 2012. My wife uses it in her classroom to teach children concepts like compound area, scale and other geometric ideas by having the students draw a floorplan on paper, scan it in and build a 3D model of their house. At first it seemed a bit complicated to use, but I figure if 12-year olds can do it, I can too!
There are a lot of blogs and videos out there explaining the ins-and-outs of using Sketchup, but I find that most of them are either written for much older versions, not explained well, or WAY too detailed for a beginner. I’m planning to write a series here at TwoMauro over time, hopefully explaining clearly the features and techniques I use for woodworking. The same tools would apply no matter how you use the program, though different kinds of modeling may require other techniques to use them.
When I’m building a model of a woodworking project, I primarily use models of lumber pieces and assemble them just as I would in the “real” world, rather than try to create a single 3D object. In the Sketchup world, these are simply 3D objects painted to look like wood. They start out as a 2D rectangle, and get “pulled” into 3D. Say I’m building a very basic box that might be used as a planter, toy chest or whatever:
- 4×4 posts for the uprights, each 2 feet tall
- 3/4″ plywood sides and bottom each roughly 2ft2
From a woodworking perspective, this is very plain but functional. But how do we build a 3D model of it? The basic plan is:
- draw a 4×4 at 2 feet tall
- draw a 3/4″ plywood floor at 2 feet by 2 feet
- copy the existing leg to be 3 more
- copy the floor to be a ceiling
- draw in the 4 sides
- paint it to look like wood
So, let’s get started!
Moving around your model
Before you actually start drawing anything, you’ll want to get familiar with moving around in your virtual world. The main ways to do this are the Orbit, Zoom and Pan tools.
Orbiting is essentially moving the camera (your view) around the center of the scene in any direction.. Think of it as the camera being tied to a string at the center of the scene, and you’re moving around in all directions, always pointing at the center. To orbit, click on the Orbit tool in the toolbar, hold the left mouse button down and move your mouse.
You can also set the view to a list of preset positions by holding the Command key (on a Mac) and the numbers 1 – 7.
If you’re using a mouse with a wheel in the middle, zooming is very simple: roll forwards to zoom in (moving forwards), or roll backwards to zoom out (moving backwards).
Without a scrolling mouse, you can click on the Zoom icon in your toolbar. Hold the left mouse button and move the mouse up to zoom in, or down to zoom out.
If Orbit is moving the camera around a central point in the scene, Pan is sliding the scene like a piece of paper. Click the Pan tool, hold down the left mouse button and drag the scene around. TIP: If you’re using Orbit, you can temporarily switch to Pan mode by holding down Shift, and you can zoom in/out with the mouse wheel. I usually use Orbit and get the best of all three tools in one!
Drawing a square
To draw the first 4×4 post, we need to start with a flat square. For the purposes of this post, we’ll assume a 4×4 piece of lumber is actually 4 inches by 4 inches, which isn’t really true but will make the example simpler.
- Click on the Rectangle tool, and draw a shape on the floor. Don’t worry about getting it exact, or even close… just draw a small rectangle.
- On the bottom right corner of the screen is a small text entry box with some numbers in it. This shows the current dimensions of the box you just drew. Click in there, type 4″, 4″ then press Enter. This sets the actual dimensions to 4″ by 4″ (NOTE! Don’t forget the comma between the 2 measurements)
- Click on the Push/Pull tool.
- Put the cursor on top of the rectangle you just drew, until you see the surface change to a dotted shading texture.
- Hold the mouse button down, and push forwards. Again, don’t worry about trying to get the height correct… just start moving it so you see the square start to get taller.
- Click in the text entry box again, and enter either 24″ or 2′ (whichever makes more sense to you)
- Press Enter to lock in the height.
Now that you have your first post, use Orbit/Zoom/Pan to line things up so that you can select the entire post (and nothing else). Select the post, then right-click on it and select Make Group. This locks the post so you don’t accidentally change it. Another way to select the parts and turn them into a group is to right-click anywhere on the post and click Select > All Connected. Then right-click again and click Make Group. Turning things into groups as you go will make your life much easier than trying to go back later and convert everything.
Making a floor
Using the same technique as the first 4×4 post above, first draw a Rectangle at 24″ x 24″ (or 2′ x 2′) then Push/Pull it 3/4″ (you can also type .75″ if you prefer) and make that a group as well.
Now you should have a floor for your box, and one post standing somewhere nearby.
Let’s put the post on top of the floor of your box… Press the Move tool, and click on one of the bottom corners of the post. By using a corner, you can move that to the corner of the floor piece and it will lock into place when it gets close. This is MUCH easier than trying to move it freehand and line it up exactly. Drag the bottom corner of the post over to the top corner of the floor piece, and watch them lock in place.
Note that they won’t be “glued” together, just snapped into location when you bring them close.
There are a few ways to copy something in SketchUp. I prefer using the Move tool with one extra twist. Orbit your view so you can see another corner clearly. Click on Move, then look in the bottom toolbar. You’ll see that it says “Option = Copy” in the fine print. (Note that I’m doing this on a Mac, so it’ll be a different key on Windows) Press that key, then use the same corner-drag as before to copy the leg to another corner of the floor. Move and Copy take some practice, but the corner trick helps a lot.
Repeat the same process for the other 2 legs… orbit so you can see a corner, press Move, then the option key, copy your leg to the next corner, making sure to drag from a corner of the leg to a corner of your floor.
Now using the same Move and option, copy the floor of your box up to the ceiling. Take the bottom corner of the floor (where it touches the ground) and bring it to the top corner of the leg.
Now for a slightly different way of sizing your rectangles – fitting them to the model rather than entering a size manually. Click the Rectangle tool again, and draw from the upper left corner of your box’s ceiling, all the way down to the bottom right corner. Note that if you haven’t been turning each piece of wood into a group, this rectangle might not snap to the edge you expect it to. You would have also had a hard time moving them as well, so you would have seen problems before this.
Now we need to give the new wall some depth with the Push/Pull tool just like before. Pull the new wall a little bit, and enter .75″ (or 3/4″ if you prefer) then make sure to make this a group as well.
Orbit around to the other sides, and repeat the process. Draw a Rectangle across the area, and Push/Pull to give it depth, then make it a group.
So now you have this white cube… not very realistic, is it? Next let’s make it look like wood with the Paint Bucket. Click the Paint Bucket tool, and a new window will appear, titled “Colors”. If you want to make your box a solid color, you can choose that from the Color Wheel, Color Sliders, or the other icons along the top of this window. The last icon is what you’ll probably use most: Texture Palettes. It looks like a brick, and has a dropdown inside it to select many real-world textures:
Choose Wood from the dropdown, and select a pattern of wood that looks right to you. When you move your mouse off the Colors window, the cursor turns to a dripping paint bucket that you can click on a Group to paint the entire object at once. Your box is made up of 10 Groups at this point:
You can Orbit around to paint the plywood faces easily. Switch between the Orbit and Paint Bucket tools to find and color each face. To paint the floor, you can either Orbit below the ground and look up at it, or if you’re precise enough you can click on the 3/4″ thick edge and it will paint the whole group.
If you care about the legs, those take a little more effort since they’re inside. Whether you paint those or not is up to you. I like to be thorough. To get the legs, you can either Orbit and Zoom until your camera is inside the box, then paint them from the inside, like so:
or you can Move off one of the faces and get a look inside, then put the face back when you’re done:
Once you’re done painting the legs, Move the face back on, and you have a complete model! For the purposes of this tutorial, I waited until after everything was built to paint them as wood texture. Normally, I would paint them as I created them so there wouldn’t be any need to chase them down later.
You can download a copy of the completed SketchUp file here: sketchTut.zip
If I were actually building this with wood, I would attach the sides and floor to the legs with screws, and not attach the top. For the top, I’d screw on either a small block of wood or a bolt on handle of some sort, so I could just pull the lid straight off. It would probably need to have the edges sanded down a bit for a snug fit, while still allowing it to move freely. If you look closely at the top of the box, you’ll notice that the 4 sides form a frame around the top piece, which sits inside the frame. Because the faces extend outwards to cover each other’s edges, they’re slightly larger than 24″ each. To save yourself the mental math (a common source of mistake in woodworking!) you can measure the model to find that they are 2′ 1 1/2″ (24 + 3/4 + 3/4) high and 2′ 3/4″ across (24 + 3/4). I used the Dimension Tool for this. Click on one corner of a piece, then the opposite corner, then move your mouse around until the dimensions are drawn where you like. These exist in 3D space, rather than simply being drawn on the face of the board, so you can offset them in any direction that works.
To help with assembly, it may be useful to experiment with the View > Face Style menu. Some of the options under there include X-Ray, Wireframe and Hidden Line, all of which give you a look inside the model without removing pieces.