Import
Vector lines
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vector designs, bitmaps cannot be read by CAM soware and need to be traced to create useable vector lines. Some CAD soware packages (including VCarve Pro) provide a built-in bitmap to vector line tracing tool. You can even start with a hand sketch. Simply photograph it and import it for tracing. It’s a powerful way to create original hand-drawn CNC project designs.
are also easily read by most CAD programs. Predesigned vector art is also readily available online—some for purchase and some for free. It’s an excellent way to find high-quality designs for CNC projects.
Bitmap images such as colored clipart and high contrast photos provide another starting point for 2-D designs, Image 2.4. Some of the common bitmap file types are .bmp, .jpg, .gif, .tif, and .png. Unlike
Image 2.4: Images saved as bitmap file types provide another starting point for CNC designs. However, they must be traced to create the vector lines in order to create the toolpaths. Some CAD programs make this easy with an auto-tracing feature.
Import
Trace
Vector lines
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Bitmap image
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CNC Router Essentials
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a single-sided model, such a carved door panel or sign. The second type is a two-sided shape, such as coin or fish. The third type is a full in-the-round shape, such as a coffee mug, human figure, or automobile. Each type becomes progressively more challenging to carve on the CNC. Single- and two-sided CNC 3-D carving are the most straightforward, and these are covered in the practice project chapters. Full in-the-round models, such as a car, can sometimes be carved using a multi-sided carving setup on a 3-axis CNC, but other 3-D models require a 5-axis CNC machine and advanced CAM soware.
Using 3-D models
CNCs excel in their ability to cut complex shapes, and this includes 3-D models, Image 2.5. There are some limits, but the first thing to understand is that 3-D models fit into one of three groups. The first is
Image 2.6: One bonus of using VCarve Pro is that it comes with a large collection of 3-D clipart models that can be dragged into the design area and quickly scaled to fit your project.
CNC compatible 3-D clipart models are also available from many sources on the Internet.
3-D clipart
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Image 2.5: A 3-D model creates a part that appears sculpted or carved.
3-D part
3-D drawing
0CNC Router Essentials
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common and can be imported directly into CAD/CAM programs, such as VCarve Pro, to create the 3-D carving toolpaths. Be aware though, that .stl files, like bitmap images, lose resolution when they are scaled up in
If you find that you enjoy using single-sided 3-D models in your designs, you will find a rich supply of them available from various online sources. A 3-D clipart library in VCarve Pro also contains a large collection of single-sided 3-D models, Image 2.6. We’ll show you how to use these in Practice Project 2. You can also create your own 3-D models using a CAD modeling program, such as Aspire, SketchUp, Fusion 360, Rhino, Onshape, and others, Image 2.7. Once you’ve created a 3-D model, you need to save it in a CAM-compatible file format. The .stl file type is one of the most
Create your own 3-D model
Part preview
Image 2.7: Creating 3-D models can be accomplished with any one of several CAD modeling programs. Aspire (shown here) has a dedicated menu of 3-D modeling tools for creating single-sided models, such as the linen fold door. Creating a 3-D model takes time and skill, but fortunately, there are lots of CNC-compatible 3-D models available on the Internet that you can import into VCarve Pro, Aspire, or other CAD/CAM programs.
CNC Router Essentials
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if the sign wasn’t CNC cut, study its layout and shape and then use those elements in your designs. If you see something you like, whether it’s painted, hand carved, laser engraved, or molded, grab the idea and archive it.
Think outside the box
As you look for ideas, don’t discount anything as a possibility. When you’re new to CNC, it’s easy to look at something and think it’s too hard. But as your skills increase, you’ll want to have more challenging projects. If you like it, capture it, and then figure out later how to execute it.
Keep your ideas organized
With today’s smartphones and tablets, and the fluid nature of the Internet, it’s easy to grab ideas no maer where you are. Maybe too easy, since it makes keeping all these files organized a challenge. There are many approaches to this with today’s technology. At a minimum, keep your ideas organized by category so you can find them as your collection grows deeper and deeper.
From inception to completion, you can let your creative juices flow with CNC work. Keep in mind that, in addition to wood, CNC machines can cut aluminum, brass, bronze, foam, and a variety of other materials. Start stockpiling those ideas!
size because an .stl shape is a wire mesh. As you scale up the model, the mesh becomes visible as flat triangular facets, which will also be visible in the final carving. The best defense against this is to use a high-resolution .stl designed for CNC design work and preview the .stl in the CAD/CAM soware before commiing it to your design.
Project inspiration
Where can you find project ideas? Well, a simple web search or a visit to Pinterest or Instagram will reveal thousands of pictures of CNC work. A lile more searching will reveal sites with ready-to-machine CNC project plans—some for sale and some for free. Aer you get some experience, lots of existing DIY shop projects (wood, plastic, aluminum) can be converted to CNC projects. It’s a great idea to network with other CNC owners: join a forum or a user group. Some of these groups hold meetings with show-and-tell time, providing a close-up look at completed CNC projects and the opportunity to ask questions about how the person made them.
Signs
Making signs is an immensely popular application of CNC machines and an excellent way to gain some experience at CNC project design and machining. Plus, existing signs are all around and can be a rich source of inspiration. You will learn a lot about sign design by just looking