Okay, I know, the graphic is way overused.  But it’s true, We Want You for sloArch!  As part of our 2010 initiative sloArch is expanding and we want your help.  Yeah, yeah, I know.  You are busy.  But we hope to make this website the portal for all things Architecture and that means you.  You are an Architect after all, or you at least pretend to be one.  So help us and let us help you!  So… what can you do?

• For starters, subscribe to The Studio! This is our new weekly podcast by, for, about, and featuring CalPoly San Luis Obispo students and alumni!  Yeah, that’s right, we’re talking about you!
• Contribute to our new forums!  Have a Revit or AutoCad question?  Need help with the IDP?  Not sure what’s the best technique for creating a model that’s sure to get you noticed in studio?  Post a question and we”ll help you find the answer.
• Write for us!  We are looking for contributing authors.  If you have a report on a show in the Berg gallery, news on a Hearst lecture, a Revit tutorial, or want to promote your latest project, we want to hear from you!  If you are interested please contact us!

Don’t let Uncle Sam down,
contribute today and help out the Cal Poly Architecture community!

In May I published my picks for Best Revit Blogs on the Web.  Coming in at number 2 was The Revit Kid and Jeff’s Lock Noob Classic Thong.  I still try to read everything Jeff writes but I thought I might stir up a little controversy and make the argument that, contrary to what the thong says, a Revit expert is one who doesn’t use locks.

I think that Jeff has it backwards.  In my experience the newcomer to Revit wants to lock everything.  I think the initial instinct is to not trust Revit and just lock things down.  Later when this user tries to change something they get a string of messages telling them constraints aren’t met and they end up getting frustrated and removing all the locks anyway.

I’m sure Jeff would argue that the Revit Expert knows how to use locks properly.  I would agree that as you experiment with Revit you learn when to lock and when not to lock.  With Revit family creation that time is only as a last resort.

So what to do instead of locking?

1. Reference lines and planes:  Hosting and aligning geometry to reference lines and planes automatically creates a strong connection between them.  The link isn’t quite as strong as a lock, under some conditions it will detach.  But for most purposes it works just fine.  Align geometry to a reference plane and flex your model.  You’ll be surprised how often this works.  Carl Gibson has a great overview of the types of Reference lines.
2. Parameters:  Instead of locking a dimension to a fixed dimension assign a parameter to it.  Using parameters gives you flexibility to easily change things later, and more importantly it lets the user of the family know what’s going on inside it without having to edit the family.  For example, create a a parameter called Table Thickness and give it the formula 0′ 2″.  This tells the user that the Table is 2″ thick and locks it from changing.  Note that locking a parameter with a formula locks it across all types in the family.

Locking does have it’s place, but I always try to make a family work without locks first.

As I mentioned in a follow up comment to Revit Families 103 – Formula Basics, Revit still doesn’t allow you to do data validation on values or formulas in families or on table data.

Still, you can build some functionality into your families to ensure that a value never exceeds a specified range or create warnings for the user of your family.

Lets start with a simple example.  In the plan view below I am showing a basic table.

Lets say in this example that we never want the table’s width to be greater than 1/2 the depth.  We have a few choices.

1. Don’t do anything
2. Display an error message for the user
3. Default to another value

Continue Reading »

Just a quick note this morning to talk about Revit and creating 3d PDF files.  As we move more and more to creating complete and accurate 3d models we really want an easy way to share these with our clients and consultants.  Consultants are usually technologically savvy enough to open RVT, DWF, or DWG files but what easy solution can we offer our clients?

Over the last couple days I’ve done some experimentation with creating 3d PDF documents.  Why PDF’s?  The only reason is because everyone is using them and knows what they are.  This is a benefit over the DWF format which requires the download of an additional viewer program.  (Autodesk True View or Design Review)  Being able to have a model embedded in a PDF that a client can open and manipulate is very appealing.  Multiple sheets could be set up with 2d images and 3d “live” models.

To get started I followed Tim  Huff’s post on “How to get Autodesk Revit models into Acrobat 3D version 8“.  I downloaded a demo version of Adobe Acrobat Pro Extended and gave it a try.  My results were very disappointing.

Here is why 3d PDF’s are not ready for use with Revit:

1. Even after following Tim Huff’s directions exactly I could not get the Print Screen key to capture a Revit model.
2. Importing a DWF into Acrobat worked, however with more complex models (an actual building with linked RVT files and design options) the building was exploded and scattered in 3 dimensions making it unusable.
3. Importing an IFC file worked, however Revit doesn’t exported linked RVT files in the IFC.  So you are limited once again to very simple models.
4. Navigation in a 3d PDF is not intuitive.  I was getting frustrated manipulating the model and trying to explain how to navigate to someone not familiar with 3d models would be nearly impossible.
5. Paying an extra couple hundred dollars per licence for the Extended version of Acrobat is a hard sell when Autodesk offers DWF creation for free.
6. Probably most importantly, the files size of a 3d PDF was substantially larger than a DWF file.  Depending on the model it was anywhere from 2 to 3 times larger.

I had high hopes for 3d PDF’s but for now we will be staying with the DWF format.  It’s a little inconvenient to require a client to download another program, but it’s much better than the time and cost required to make larger less functional (or unusable) 3d PDF’s.