Google SketchUp is a 3D sketching tool. To quote the Google SketchUp website "Google SketchUp is software that you can use to create, modify and share 3D models. It's easier to learn than other 3D modeling programs, which is why so many people are already using it." But viewing SketchUp as a simple sketching or modeling tool would sell it very short, as I will explain in this short overview. However, in addition to my overview, you may also want to read the article that first made me aware of SketchUp. I discovered it while reading Fine Woodworking Magazine,  December 2007, No. 194, "A Quick Course In SketchUp", page 78. It is a good short course in designing with SketchUp. In addition, I have provided a Beginner's SketchUp Tutorial in eight parts which can be accessed from my Google SketchUp page.

SketchUp comes in two versions. Google SketchUp Pro 6 and Google SketchUp 6. The major difference between the two is in their ability to save/open/export/import files from/to other CAD applications such as AutoCAD and TurboCAD, and their price. SketchUp Pro is richly supported in exporting and importing features, costs about $400 and is used commercially. SketchUp is free and targeted for the general public to encourage its use and the sharing of creative 3D models. Both are available for download directly from the SketchUp site. So far I have used only the free version and found it to be very powerful and intuitive. And while the free version is limited in save/open/export/import features, it does allow you to import .DWG (AutoCAD native) files. This is enough capability to allow me to save my TurboCAD files as .DWG files and then import them to SketchUp which is all I really need.

To give you an idea of the power of SketchUp look at the completed drawing of a six pane oak hutch I am currently working on (see picture at left). If you compare this rendered picture to the TurboCAD rendered drawing, the first thing you notice is that you can still see the dovetail outline. SketchUp lets you render with the edges outlined or not. I find this more helpful in picturing the final piece.

Another nice feature is the X-Ray capability. The picture at right shows the base only. Notice that you can see the construction within the unit. In TurboCAD you would use the basic line drawing, but its presentation is confusing. SketchUp weights the line drawing so that you get a feeling for depth and outside surfaces versus internal pieces.

If I want to see a section of the base unit all I have to do is define a sectioning plane and move it into position as shown in the picture at left. This is a section in the vertical plane, but I could make it a complex section by simply rotating the plane in one or two axes. Sections can be saved as a view and can be dimensioned just like any other view.

One anomaly you may notice if you look at this section in detail is that you can see inside the pieces that make up the structure. For example, you can see inside the draw bottoms and runners. This is because SketchUp is a surface modeler, not a solid modeler. More on this later.

Richly featured CAD tools such as TurboCAD and AutoCAD allow you to draw complex solids such as car engine blocks or coffee mugs, i.e. things with lots of curves. SketchUp has far fewer features and require you to work with more primitive drawing elements. At first blush you get the feeling that it's not possible to draw these complex features in SketchUp. But that couldn't be further from the truth. If you are an experienced user of tools such as the two mentioned above you have to learn to let SketchUp provide you a more intuitive and simpler way. If I had to describe SketchUp in one word it would be intuitive. The way it works is more natural to the way people draw if they were drawing by hand. This requires you to come down the learning curve a bit and re-climb it. But once you do it is more comfortable and I believe quicker. The picture at right shows the ogee feet I designed for this piece.

One example of SketUp's more intuitive approach can be demonstrated by rotating a part. In the picture at left you can see that all I did was select the part (it's outlined in blue), grabbed the protractor and began rotating. If I am going to rotate it to a standard angle such as 90 degrees the built-in inference engine will let me know when I am there so I can click it complete. If I want an unusual angle I can type it into the window at the lower right which now reads 13.99 degrees. But I don't have to place my cursor in the box at the lower right. The inference engine knows that if I type a number at this stage it must be an angle. So I simply type 13.99. The inference engine is very powerful and frees you up from having to manage and select viewing planes. I can draw a complete piece of furniture without ever moving the axis or thinking about a work plane or even a coordinate system. Try that with TurboCAD or AutoCAD!

SketchUp's presentation style, simple dimensioning and inference engine make it easy to create exploded and dimensioned views as that at right. This simple view provides all the information required to mill the face frame of the base cabinet for this hutch.

As mentioned earlier, SketchUp is a surface modeler, not a solid modeler. That means it represents solids as surfaces. For example a cube is constructed by creating six connected surfaces. In a solid modeler if you were to section or slice the cube you would have two new cubes. In SketchUp you are left with two halves of an enclosure and you can see into each half. This is a real problem if you are designing and modeling mechanical parts, especially if you have to derives such things as weight, center of gravity and mass from your drawing. But for furniture or architectural design this is not a problem.

When comparing SketchUp with big brother CAD tools it also falls short in other areas such as logical operations and splines (complex curves). Logical operations give you the ability to add parts to create a new one, or to subtract two parts. For example, suppose you drew the sides of a drawer complete with tails and now wanted to draw the back with pins. Rather than draw the pins, start with the drawing of a rectangular board sized correctly for the back. Copy one of the sides and place it at right angles to the board. Then subtract the copied side from the board and voilà! You now have the board with pins on one end. Repeat the step on the other end and you are done. This is more difficult in the stock SketchUp. However, one of the nice parts of SketchUp is that it allows plug-ins that enhance its feature set, and there is a world wide community out there generating free downloadable plug-ins called Ruby scripts. Almost any feature you want can be found on the web.

As an example, recall the section earlier, where you could see inside the drawer bottoms and runners. You can download a Ruby script called SectionCutFace.rb written by  TIG © which places a command on the context menu. This command restores the faces on the exposed ends. A little clean up is required, but the results produces a much more readable picture. Compare the picture at right with the previous section.

There are hundreds (perhaps thousands) of Ruby scripts for SketchUp on the internet, and most of them are free. I have a few favorites:

• add_construction_point.rb    This script costs $4.00
• add_hidden_layer.rb            (This one is a must!)
• bezier.rb
• bezierspline.rb
• centerpoint.rb
• clinetool.rb
• CutListAndMaterials.rb        (Works with CutList Plus, though a little clean-up is needed.)
• deletecoplanaredges.rb
• dim_angle.rb
• jointpushpull.rb
• midpoint.rb
• projection_extension.rb
• PurgeAll.rb                         (Helps to keep file size down.)
• SectionCutFace.rb
• startup.rb                           (Forces SketchUp to startup with the Select tool active.)
• zoom_selection.rb

I use more scripts than listed above, and I find new ones every few weeks, but I find these to be particularly useful. I also modify most Ruby scripts to put them on the menus I desire, instead of the default lumping of all scripts to the Plugins menu. Also I tailor the folder that is targeted anytime a file is generated by a script - I find the default folders a nusance. Ruby scripts can be found in a number of places on the internet. Here are two I keep my eye on.

Ruby Library Depot
Smustard(TM) - the Companion to Sketchup(TM)

If you are a woodworker you may want to visit "Design. Click. Build.", the Fine Woodworking SketchUp Blog. This site is dedicated to teaching woodworkers SketchUp for use in the design of custom furniture and  the creation of working shop drawings.

In summary, this tool is (or can be configured to be) very powerful. It is more intuitive than its more feature rich and sophisticated big brother CAD tools, and the price can't be beat. If you are new to modeling or CAD drawing the learning curve is relatively small. If you are an experienced CAD user be prepared to undo some learning, but look forward to a more comfortable intuitive future. Best of all the presentation style of the rendered drawings are much more readable and pleasing than the staid presentations of TurboCAD and AutoCAD.

If you download SketchUp and want some completed furniture designs to practice with, click Free Plans here or the top menu above. Feel free to contact me with any questions.