Sketchup Sketchup

FEATURE SEGMENTS with SketchUpSketchUp David Heim

Photo: From Segmented Turning, by Dennis Keeling, published by The Taunton Press. Used with permission.

A segmented bowl and its SketchUp representation. 3-D modeling can help you create accurate segment patterns and a cutlist.

lanning a segmented turn- architects, product designers, and lines, the Tape Measure tool measures ing takes considerable preci- others worldwide. lengths and places layout lines, and P sion and patience. There are SketchUp offers three significant the Protractor tool sets angles. For a couple of computer programs benefits. One, it runs equally well turners, the Follow Me tool is criti- designed to help you determine on Windows and Mac. Two, it’s free cal. This tool extrudes a shape along the size and shape of the staves or (a Pro version costs $700, but most a path, and it allows you to generate a wedges you need, but I prefer to use users don’t need it). Three, SketchUp 3-D version of the bowl with just two the SketchUp 3D design program allows you to create a full-color mouse clicks. (sketchup.com). It is increasingly 3-D model of a turning, with every SketchUp has color-coded on- popular with woodworkers, turners, individual segment perfectly shaped screen axis lines and numerous and positioned. You can also use the prompts to keep you from getting 3-D model to generate absolutely lost in space. For instance, if you JOURNAL ARCHIVE accurate, full-sized patterns for want to draw a line parallel to the CONNECTION the segments. red, or left-to-right, axis, watch

or turners who have never tried segmented turning or for those F who would like a refresher on the basic concepts, here is a simple, For more basic information easy approach to turning a segmented Turning Your First bowl. This quick, accurate method will for the line following the cursor acquaint you with the fundamentals of segmenting, which you can then apply to more complex pieces. The SEGMENTED bowl presented here makes use of a Jim Rodgers solid layer of wood for the foot and four progressively larger rings, each BOWL on segmented turning, one comprising multiple segments cut at predetermined angles. SketchUp basics to turn red. Orbit, Pan, and Zoom Segment-cuttin As you would imagine,g segmentedsled projects require careful attention to creating a blank prior to turning. see “Turning Your First The table saw is my preferred tool for cutting segments, and a sled with a fence set at the correct angle When you work in SketchUp, you tools make it easy to navigate and is the best way to produce identical segments. Some time invested up front creating a good sled will help you far into the future. I recom Segmented Bowl” (AW vol mend making and using a Wedgie - Sled, a simple fixture designed by renowned segmented turner Jerry Selecting wood Bennett. Plans and instructions for You will need to determine which always work in three dimensions view the model from any angle. building this sled, as well as helpful wood species to use; I had some very Make a drawing videos, can be found at Jerry’s dry Eucalyptus cut a few years ago Make a full-sized drawing of your website, segeasy.com. Regardless of from a friend’s yard. Mill the wood bowl on graph paper with your 30, no 5, page 18), by Jim the sled design you choose, the goal to the desired thickness you want desired profile. This drawing will help is to be able to cut desired angles for each level, or ring. I chose ⅝" you determine the ring diameters and accurately and with repeatability. (16mm) thickness. It is important thicknesses as well as the segment that you select wood that is thor sizes required. Allowing for extra wall oughly dry, with moisture content and always full size. Clicking the blue question-mark thickness now will help you mini - JOURNAL ARCHIVE of six to twelve percent. Using mize any problems you might have CONNECTION green, or unseasoned, wood intro later in aligning the rings or turning- Jim Rodgers has written duces a greater likelihood of wood the bowl. Next add horizontal lines to

Rodgers. AAW members Part 1: Cut Accurate Segments - previously in indicate the foot and ring thicknesses, American movement, which will cause Woodturner based on the thickness of the wood on segmenting. glue joints to fail. His 2005 article on cutting you will be using. Add a centerline to accurate segments (vol Plan your bowl the drawing and number each level, 20, no 4, page 24) offers Segmented Most tools in SketchUp work icon at the bottom of the SketchUp Unlike other kinds of wood or ring, of the bowl from the base helpful information, Turning School turning, segmented projects upward ( Figure 1 including an alternate - ). By Jim Rodgers 24 require detailed planning of Note that drawings made with sled design and tips on gluing segments into can access all past American Woodturner Winter 2005 the piece you wish to create. For sophisticated software or using rings. AAW members can access all past this project, I decided on a small journal articles online at woodturner.org. trigonometry functions will render popcorn bowl that would fit in more accurate results, as a simple your lap—about 3" (8cm) tall by 7" two-dimensional drawing cannot (18cm) diameter. account for the three-dimensional just like their real counterparts. screen opens a window that aspect of the bowl’s curvature. This is why allowing for extra wall thickness journal articles online 18 18_SegmentedBowl.indd 18 American Woodturner October 2015 For example, the Line tool (with a explains how to use whatever tool

at woodturner.org. 9/9/15 2:04 PM pencil for a cursor) draws straight you have selected.

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Figure 1. Begin the model of the turning Figure 2. Use the profile as a reference to Figure 3. Make the bowl profile into a with a profile of the bowl. Anchor it where size and position one wedge for each ring 3-D shape and merge, or intersect, it the colored axis lines meet. in the turning. with the stack of wedges.

Building, not drawing beginning with SketchUp’s own user Use SketchUp’s Line and Arc tools to With SketchUp, you don’t simply guide. Go to sketchup.com/learn. draw the profile of the bowl or vessel make a perspective drawing of an you want to make. Once you are satis- object. Rather, you construct it piece Plan a segmented turning fied with the shape, make the profile a by piece, much the way you would The video accompanying this component. It’s a good idea to anchor in real life. Each time you add a article shows all the steps involved the edge of the profile at the origin, new piece, you need to make it what in using SketchUp to create a model where the three axis lines meet. The SketchUp terms a component—for of a segmented turning. Here are blue, or vertical, axis line makes an ideal woodworkers, a component is basi- the basics. centerline for the turning (Figure 1). cally a virtual piece of wood that’s separate from anything else in the model. This is the most important thing to understand about Erase and copy SketchUp. If you don’t create components, all you make is a series of random lines that won’t add up to anything. There are two other key concepts to master. One, draw components in place whenever possible to help ensure accuracy and save time. Two, rely on SketchUp’s ability to deliver the precise lengths, radiuses, and distances you need. If you want a line exactly 125⁄16" (31cm) long, for instance, begin drawing the line, type that length (without the inch Figure 4. After running the intersection Figure 5. Copy the shaped wedges around routine, erase most of the drawing so you a circle to finish the bowl shape. Paint the sign), and press Enter. are left with wedges that are now shaped segments with color to match the woods You can find plenty of online tuto- to match the bowl profile. you will use. rials to learn more about the program,

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Work in SketchUp much as you it a component, then move on to the made. Click on one and drag it to would in the shop to create com- next layer (Figure 2). the main SketchUp screen. Now ponents for the base of the turning To finish the model, use the Follow you can add dimensions with the and one wedge for each ring you Me tool to make the bowl profile a Dimension tool or orient the com- will need. Use the profile as a ref- 3-D shape. Execute a series of component to print a full-sized pattern erence to size and position these mands to intersect the bowl shape (Figure 6). components. with the wedges (Figure 3). After It’s easy to draw the wedges with much erasing to get rid of waste, Easy and versatile SketchUp’s Polygon tool. You can you’ll have a set of shaped segments SketchUp isn’t a one-trick pony. set the tool to match the number of (Figure 4). Copy and rotate those seg- You can use it to design just wedges you need in each ring (type ments around a circle to complete about anything—the table your the number you want and press the bowl. segmented bowl sits on, the Enter). That will give you the exact With the turning model complete, room the table sits in, the house angles for the wedge without any use the Paint Bucket tool to apply a containing the room, even the further measuring or calculating. color or wood texture to each segment neighborhood for the house. If you For the bowl shown on these pages, for a reasonably accurate preview of download SketchUp at breakfast, each ring has eighteen wedges, so I the actual piece you want to make you can be making good models by set the Polygon tool to generate an (Figure 5). dinnertime. I encourage you to give eighteen-sided figure. That auto- To retrieve the original wedge it a try. matically produces wedges with components for full-sized pat- David Heim is a frequent contributor of 80-degree angles on the outside terns or measured drawings, go to articles and SketchUp illustrations to the corners. With a little more work Window>Components. This opens journal. He is a member of the Nutmeg using the Offset and Push/Pull tools, a new window showing thumbnail Woodturners League and can be reached at you can generate a 3-D wedge. Make images of all the components you [email protected].

Create segment drawings You read the article— now see the video! This article has an accompanying online video in which David Heim shows you, via real-time screen capture, the key elements of using SketchUp for planning a segmented bowl. To view the video, visit tiny.cc/SketchUp or scan the QR code with your mobile device.

Figure 6. Use copies of the original wedge shapes for a measured drawing or full-size patterns.

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