Best Free CAD Program

Seeing your imaginings materialize and take actual form, now that's what it's all about, right? And if you can command your PC to perform all the gory drudgeries of that undertaking, so much the better. Luckily, others have been thinking along that same vein for decades, so today you can enjoy the culmination of all their toil and sweat. It's called Computer Aided Design. Keep in mind of course that this sort of software tends to be insatiably complex. It's not easy fitting a complete 3D workbench onto a two-dimensional monitor screen, while still maintaining operability by plebeians. Many people employed in engineering trades have endured long and laborious college courses to acquire skills in the use of these behemoth programs. So know what you're getting into. As the ancient sages were so often heard to proclaim, "The electronic brain is a perfect servant, but a lousy master".

If you've already used drafting software at work, then you've likely heard of industry giant, AutoCAD, which has enjoyed a near monopoly. Its drawing exchange file format, .DXF, gets revised continually and competing software has to keep step. This is one of the reasons why you'll often see older versions of expensive CADD software offered for free on the Internet, usually feature-limited or use-limited or time-limited and support-limited, and always with lengthy application forms for licensing. These software companies desperately want their share of name recognition and to accustom people to the use of their product, with the hope of one day licensing their big-ticket "Pro" edition to whoever it is you know with deep pockets. It would astound you the number of extravagant packages that can be had for download and free use... packages that are essentially AutoCAD clones. Be forewarned that their system requirements tend to be very hefty. Ideally, your PC should have two or more gigabytes of memory, a monitor capable of 1280 x 960 resolution, fast dual processors, a state-of-the-art graphics card and a motherboard that is extra well-cooled.

But Gizmo won't be pursuing the giant AutoCAD clones in depth here, because our readers aren't so much concerned with getting impeccably-perfect blueprints down to some factory in Mexico to produce 2.5 million high-valued widgets. Those who are should, in all probability, shop elsewhere for software. And those who are planning any major or risky undertakings, such as tearing out an exterior wall of their home to erect a second-story balcony …they also should seek out the best guidance money can buy to ensure the safety of their constructions. None of the software that Gizmo's has cited below claims to analyze structural integrity.

With Google Sketchup you'll find not only a near limitless wealth of capabilities, but also a lucid breezy interface that won't put your head into a swoon. This exceptional package is a modestly trimmed-down version of Google's Sketchup Pro. Yet the free version affords the novice designer a veritable dream come true. With innovative tools like the Push/Pull and the Follow Me, you can count on achieving your desired results. But it doesn't stop there. Sketchup incorporates so many advancements that I am hard-pressed to enumerate them. It employs its own scripting language, called Ruby, which multiplies the software's power exponentially. And you won't be standing all by your lonesome self in the pursuit of said power. An army of fellow Sketchup users have heralded the way and devised scores of pre-programmed add-ons that are a cinch to download and put into immediate use.

There are numerous add-ons and plugins that expand Sketchup's fundamental abilites, giving it new menus and new menu entries. There are also enhancements to Sketchup's production capabilities, for example, affording integration with some exquisite photo-realistic rendering engines and conversion of Sketchup 3D objects into non-native file formats for use in other packages. And what is perhaps the most appealing feature of all is Google's ever-growing libraries of 3D objects and scenes for import into your designs. These number in the tens of thousands and no doubt, you'll have Google's well-honed search engine to use in locating the elements that you seek. Sketchup also affords full integration with Google Earth, so the building you model can literally claim a place on the map. And don't worry about guidance, for you'll find numerous tutorials and video guides, as well as a helpful user forum, at the Sketchup site.

Sweet Home 3D (SH3D) is a software package that is sure to tickle every bone in your body. With this program you can model your dream home, along with all of its cherished appointments, and then watch it come to life. You can start simple, with just the bare walls, and if you already have an image of your intended floor plan, this can easily be imported into Sweet Home 3D to serve as a basis for the design-to-be. The user interface of SH3D is as intuitive as it gets; drag and drop furnishings from the built-in catalog onto your floor plan. Clear graphic handles then make it easy to move and rotate the items, shrink or enlarge them, and change their height or elevation. Arrow keys also work for nudging things into the precise desired positions. Contextual menus are always just a right-click away, affording yet more powerful functions. You can bring up a dialog box for an item and customize it in a number of ways, not just its position and size but color and finish as well. You can apply textures to all of your furnishings, floors and walls. (NB The term "texture" is used in this software to mean what some may more commonly know as an "image map".)

If you should find SH3D's built-in catalog of furnishings inadequate to meet your needs, then go online to sweethome3d.com and there you'll find hundreds of additional models free for the taking. In fact, entire libraries of such models can be imported into the program. Or, with a little ingenuity, thousands of additional object models can be readily acquired. There is the entire gallery of Google Sketchup models at your disposal, and the Internet is chock full of 3D models, if you just take the time to follow some links and use your search engines to advantage. Sweet Home 3D can import 3D objects in any of four file formats: .DAE, .OBJ, .3DS and .LWS. I mentioned the vast libraries of Sketchup models but take note that these will have to be converted. The Sketchup program can convert them to DAE format or employ a user-contributed Ruby script to convert to OBJ format. A free web service may also be of help in doing such conversions, for example, Babel3D.com.

Once you've finished your home design and tweaked every niche and corner to your liking, the fun has only just begun. Then it's time to move the camera into your model home and let Sweet Home 3D's ray-tracing rendering engine take snapshots or produce walk-through videos of your creation. Check the SH3D site for an even more advanced photo-realistic rendering plugin available at no charge. Keep a watchful eye on this site, as more models and more plugins are sure to be made available. There's a complete user forum as well, plus plenty of guidance.

The SH3D package is written entirely in the platform-independent Java language, so it should run okay under Windows, Linux, Mac OS and Solaris. It will also run in your web browser, so one option is to simply use the package online at sweethome3d.com. This software is free and open-source and is available in English plus more than a dozen other languages.

I examined a number of traditional CAD packages that are offered for free use, each with its own particular flavor of licensing restrictions and/or functional limitations. I've settled on progeCAD Smart! as a recommendation for the budding architects and engineers among our readers. Yes, there are a few features trimmed out, as compared to progeCAD's Pro edition, features such as PDF conversion, raster image insertion and photo-realistic rendering, but the package is still truly awesome, and it's yours to keep forever, free of charge. The main licensing restriction is that the software be used for purely personal pursuits and not for business production.

Oh, and one other thing to keep in mind with this is that any DXF file format revisions beyond 2009 are not likely to ever be supported. If you can live with those terms then by all means download this nearly 100 MB colossus and put it through its paces. You'll find it an exceptional utility, feature-packed, fully 3D savvy and incorporating some nifty extras, such as Wintopo for vectoring raster images, plus availability of the entire ALE libraries of more than 11,000 pre-drawn blocks. I could go on about the many features of this highly-advanced drafting package, but I'll just finish by giving my earnest assurance that you will not be disappointed. If you run into any snags, progeCAD 2009 Smart! has its very own user forum on the Web.

Blender is the complete software package for 3D modeling, texturing, rendering, animation and physics. It has a complex but merciful user interface, and the entire repertoire of its capabilities are made available through a scripting language, so the creation of 3D games beckons. The software can import from and export to more than 20 different file formats. There is a large and growing community of Blender users who've already contributed numerous add-on scripts that can make your going easier. You'll find a generous number of fine tutorials to guide you up the steep learning curve of this monumental program, plus an active and helpful online user forum. If it can be imagined then it can be realized, with Blender freeware.

Sculptris Alpha 6 is a free early version of a program that later went commercial. It's a great utility for working with OBJ files, tweaking them to your liking and then applying textures and colorization. Of course Scupltris can also create 3D objects from scratch, beginning with primitive spheres and planes and then treating them like clay: pinching, creasing, inflating and elongating until the model arrives to your expected form. There are helpful tutorials and a user forum to give you a leg-up. This is some truly exceptional and innovative software.

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