More on Revit export options for 3D Printing

Last week, Dolly Haardt discussed and showed us a video about the STL Export add-in tool for Revit. Good stuff!

A few months ago, on the LinkedIn group site called 3D Printing for Architects, there was some related discussion about the best methods to get Revit designs to 3D printing. Some alternatives to STL were presented as options. For example, Zvi Grinburg of CALIBER Engineering and Computers Ltd., a Z Corp. partner in Israel, posted this comment:

I don't want to spoil the STL party, but the most successful models we received and printed from Revit were those with in ACIS SAT format. I feel much more confident when the model is totally editable. Being able to edit the solid file - eliminates all the architectural typical surprises of thin walls, delicate features, non-touching objects and floating elements. It also enables for intelligent separation which can make a difference between a good and an awesome model. Most significantly, it gives a chance for proper model hollowing and draining, which can reduce a model cost from "out of question" to comfortable.

Now, I don't say that all models should be edited in CAD, but Revit is a good example of architectural CAD that can provide good solid data.

When we receive polygon files (VRML, STL, 3DS etc) we are at the mercy of the designer's ability to comprehend what a physical model is all about. At the alternative cost of numerous iterations, we take the time to review the model and make it ultimately and pleasantly printable.

FWIW, my tool for geometry editing is KeyCreator. This is a pure geometry free-form hybrid modeler (wireframe, surface, solid) that has great control and geometry management facilities and can edit almost everything as if it was natively created.

Matt Mondo from Impact 3D Models, a service bureau specializing in architectural models, posted:

I have to agree with Zvi. Many architects in our area are new to 3D printing and when we usually receive a direct export from Revit, we have the issues that Zvi mentions. It's great that there is an export tool, but it must come with the understanding that it is not a "one click" process where you have an instant 3D printable model; the customer needs to set up their focus (e.g exterior only, etc) before export.

I know that others prefer to take the digital model from Revit into 3dsMax to prepare models for 3D printing, especially when color and texture are desired (VRML export). Some use Rhino in their workflow, which has the added benefit of exporting a ZPR file directly into ZPrint. What is your preference?

http://www.zcorp.com

Model Transformation: Revit, Google Earth and 3D Printing

Today’s guest blog is from Dolly L. Haardt, LEED AP, Architectural BIM Specialist, Microsol Resources, New York City.  Microsol is an Authorized Reseller for Z Corporation. 

It’s amazing what you can do with a Revit project, from publishing it into Google Earth to printing a 3D model, the capabilities seem endless. Some of the most powerful aspects of Revit are the Add-Ins, which essentially are plug-ins to the software to expand its functionality. I’m going to walk you through the Globe Link and STL Add-In tools, so that you can familiarize yourself with how to publish a Revit mass into Google Earth and how to export an STL file to print a 3D model.

First let’s talk about Revit and Google Earth. For those of you that understand the basics of Revit, you know that Project Location is extremely important and can cause havoc down the road if ignored. The beauty of linking your model to Google Earth is that you can import the latitude and longitude of a particular location into your Revit Project. To start you need to make sure that you have the Globe Link Add-In tool; it can be downloaded at subscription.autodesk.com. This is a free tool if you are an Autodesk subscription customer. Once you download and install the Add-In, you will see the commands listed under the External Tools Menu. Then, locate your project in Google Earth and simply ‘Acquire’ the location in your Revit Site view. Once you mass out your design, confirm that you are in a 3D view and ‘Publish’ your model to Google Earth via the Add-In menu. It’s basically that simple. Here is a link to a video I created showing you the process.

Now let’s discuss Revit and 3D Printing. There is a free Add-In tool that you can get at labs.autodesk.com called STL Exporter for Revit Platform. This gives you the ability to take any Revit model and export it out to an STL format. The 2011 Autodesk tool has new features that the 2010 tool did not include, so it is well worth the upgrade. Similar to the Google Earth process, you will want to make sure that a 3D view is active before exporting. I do want to clarify one important point, similar to the process for photorealistic rendering, for 3D printing there is pre-processing work that needs to be done. Your model needs to conform to standards depending on the final output. For example, let’s say you want to bring this model into ZPrint, which is software provided by Z Corporation for printing on their various 3D printers, you will need to adhere to certain guidelines: a water tight model, no inverted surface normals, and minimum element thickness. Once you have gone through this process, you can bring the STL file into ZPrint and then check it in ZEdit Pro for any issues that may need repair. Once you get the ‘Congratulations’ dialog box you are ready to print. Here is a link to a video I created showing you the process.

Both the Globe Link and the STL Export tools are quick to install and master. With a little bit of guidance from my videos, I hope you have the opportunity to test out these latest features. I have found that showing clients their project in Google Earth and printing out 3D massing models helps communicate design concepts most successfully. Keep in mind that these are just a couple of the latest tools out there to enhance your workflow.

http://www.zcorp.com

Tools to Prepare Google SketchUp Designs for 3D Printing

Over the past few years of monitoring architectural practices, we are seeing more and more interest in 3D printing from Google SketchUp designs. We hear architects tell us that SketchUp is easy to use, especially in the early design stages where multiple iterations are needed to move a project forward.

This is good news and bad news for 3D printing. The good news is that 3D printing adds the most value to a design process by enabling the physical visualization of multiple concepts as early as possible. The bad news is that SketchUp behaves more like a rendering tool, not like a solid modeling system. With a rendering tool, designers must take more care in preparing their model for 3D printing to ensure a water-tight model. To be fair, we have seen enhancements in Google SketchUp v8 which begin to address the solid modeling issue.

In the meantime, a few experienced vendors have stepped in with tools to assist with preparing models for 3D printing. One supplier, LGM Model, has created a SketchUp plug-in called CADspan -  CADspan will resurface your SketchUp design and essentially shrink-wrap it to create a single water-tight model for 3D printing.

Another well-known vendor, Materialise, has formed a business unit called iMaterialise. They offer an i.materialise service which will 3D print your model. They also developed a Google SketchUp plugin to assists in the creation and 3D printing of architectural scale models. iMaterialise recently sponsored a design contest using this SketchUp plug-in module. You’ll find pictures of the winning designs here: http://picasaweb.google.com/i.materialise/IMaterialiseSketchUpContent#.

Has anybody heard of similar SketchUp tools? Please share your experiences.

http://www.zcorp.com

Timber House

Today's guest post is by Mark Cook, Z Corp. VP of Research and Development.

One of the things I love about working here at Z Corp. is when I am able to help someone discover the unique capabilities of 3D printing, specifically how ZPrinting can help solve real problems.

A few weeks back I ran into an old friend, during a wine tasting event at a local vineyard, who I had not seen in many years. As is often the case during these chance meetings, we both talked at length about what we had been up to over the past few years. The last time I saw him I must have just recently started my career at Z Corp. because he seemed to remember me telling him something about models. My friend is a local architect specializing in high-end custom homes.

Like many individual or small firm architects that have been around for a while, this guy hand draws most of his concepts and many of his detail drawings. His early design decision process involves sketching concepts, reviewing them with the customer, and re-sketching until they both agree on what is to be built. This is time consuming and at the end to the day there is always a risk that the sketch did not accurately represent the final building. How close the end product is to what is expected depends upon the quality of the sketches, as well as the customers’ ability to interpret them or to visualize the final building from the sketches.

Recently some of the younger architects working with my friend started using 3D software to turn early concepts into more realistic renderings in an effort to better communicate and make decisions at this early design stage. As luck would have it, they were in the midst of a project with a client where the husband was in the building profession and, because of his experience, could easily interpret drawings. The husband and wife were in disagreement about a particular detail - whether an entire wall in their new great room should be made of stone or just the section above the fireplace. The architect had rendered the room and shown them the renderings on the computer screen, but a decision had yet to be made.

I offered to take the 3D data from their software and print a model for their next client meeting on the following Thursday. I was able to export the 3D data, including texture map images for the wood, stone and other surfaces. I delivered the completed ¼” scale model in full color on Wednesday afternoon. My friend was amazed, his client was amazed, and I was very happy to help. The husband was finally convinced that his wife was right. Through a chance meeting at a local vineyard, I was able to help a friend solve a real issue by improving communication using Z Corp. 3D printing technology.

Click here and scroll to the bottom of the page to see a sampling of ZPrinted architectural models.