Measuring Up
From the beginning, some of the most valuable information that comes from 3D models is also some of the simplest to retrieve. Visualization and quick precise measurements are the things I have been asked to provide more than any other piece of information during my career.
Thanks to the measuring and sectioning tools in Navisworks® Manage, it is easier and faster than ever to provide your team with the information they need. And because these features are also in Navisworks Freedom and 360 Glue, you can help lighten your workload by empowering your team to find the information themselves.
Measure Tools
The measuring tools in Navisworks have some simple commands that make them very powerful. But first we’ll look at the measure window and how to read it.
Figure 1: Measure window
The measure window consists of four rows: Start, End, Difference, and Distance. At the very top are all the measure tools: Point to Point, Point to Multiple Points, Point Line, Accumulate, Angle, Area, Shortest Distance, Clear, Transform Objects, and Convert to Redline. These same tools can be found under the Review tab.
The measuring tool is pretty straightforward, but there are a few things you should understand before measuring. The Start and End rows have three columns. These columns represent from left to right the X,Y,Z coordinates of your measurements based on where your 0,0,0 point is in the project. Navisworks gives you the option to lock your measuring direction to the X,Y,Z axis and parallel or perpendicular to a surface. This is important to remember because if you want to pull certain measurements from your Navisworks model, you need to pay attention to how you export your models or how you position them in Navisworks.
For example, if I want to get the flat dimension between two pipes running straight but at different elevations, I could use the Point to Point measuring tool. After selecting a point on my first pipe I can hit X or Y on my keyboard and Navisworks will lock the measurement to that axis. But what if my Autodesk® Revit® model was rotated 15 degrees and I exported using Shared Coordinates? The X,Y axis in Navisworks would be off, so if I tried this measurement with a rotated model it wouldn’t work. I would either need to zero out my rotation in Navisworks by selecting the entire model and opening its Units and Transform, or I could change the exported setting in Revit to export using Project Internal coordinates.
Another way I could get that measurement if my model was not rotated is by using the shortest distance tool. After selecting the two pipes I can hit the Shortest Distance measurement and Navisworks will (frustratingly) change my view and then pull that measurement. The measurement will be at an angle which is not what we were looking for, but if you look in the Measure window in the Difference row you can see the flat measurement along the X axis. The measurement can be very different from the shortest distance measurement as shown in Figure 2
Figure 2: Reading the difference
Speed Sectioning
Sectioning can be a very useful tool during coordination. Sometimes you will have the luxury of sectioning before a meeting and preparing views, and other times you will need to section on the fly while everyone is waiting. There are quite a few tools for sectioning, but I will only cover the ones I have found most applicable to BIM coordinations.
When preparing views before a meeting Saved Viewpoints are great because they will keep your section cuts, redlines, and hide properties so you can set up views that will clearly display an issue.
During a meeting I recommend having the Section Plane Settings window open even when sectioning is turned off.
Figure 3: The sectioning planes window can be turned on under View/Windows/Sectioning Plane Settings
Sectioning on the fly can be fast and easy. You can try to use the Top, Bottom, Front, Back, Left, or Right standard sections and then move them to the desired location. At times it is also helpful and faster to use the Align to View cut, but your camera is often not straight so your cut will be at an angle. The cut I use most often is the Align to Surface cut.
You may have noticed that throughout your Navisworks models there is no shortage of flat surfaces in every view. Whether it be a wall, ceiling, beam, duct, or even hanger, there are plenty of flat surfaces you can use to section quickly with the Align to Surface cut. Within two or three mouse clicks you can have a perfect section cut; when you select Align to Surface your cursor will turn into a crosshair. Use your crosshair to select a flat surface close to where you would like your final cut. Once you select your surface and your section cut is turned on with the check box next to it, you can adjust the cut with the Move command and you’re done.
You can add two or more section cuts just as quickly until your scene shows what you need it to show. And if you clicked on the wrong surface or want to pick a different surface, just use the green Re-select button to the right of your cut.
I recommend saving a viewpoint after making important section cuts that you might want to see later.
BIM 360 Glue
As I mentioned earlier, many of the measuring capabilities we have in Navisworks Manage are also in Freedom and BIM 360 Glue.
Because this information can be so important we want our project team to have access to it, we have found that the easiest way to empower them to use the models is through BIM 360 Glue.
Training anyone on Glue takes less than half an hour, and they will be able to navigate a model, view redlined saved viewpoints, and pull their own dimensions.
The Point to Point measuring tool in Glue has a feature that I think Autodesk should consider putting into Navisworks—that is when you take a point-to-point measurement it automatically shows you the X,Y,Z measurements in different colors.
Figure 4: BIM 360 Glue Point to Point measurement.
These simple tools can be easily learned and taught to the project team, freeing you up for more technically intensive tasks.
Mark Hunter is a BIM Manager for C.W. Driver, a large general contractor in Southern California. The firm is highly regarded throughout the design and construction industry for implementation of BIM innovations on each project, and for creating customized software plug-ins to increase the efficiency of the latest software releases. Mark has a video showing how section cuts can be pushed in walkthroughs to the extreme on his blog: http://navisninja.blogspot.com/ Mark can also be reached at mhunter@cwdriver.com, or at 909.945.1919.
