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| MicroStation V8 in 3D - The Drawings Are So Easy |
| Part 2 |
| Part 3 |
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MicroStation has always been a 3D design application, but it is more commonly used as a 2D "electronic drawing board" – what a waste!
Why Do It In 3D?
Using MicroStation to model objects in 3D is not difficult, especially with the capability built into the latest version. The advantages of creating 3D models are huge – we can virtually prototype our design before a dollar is spent on manufacture. Added to this, problems and solutions that would be invisible in a 2D design often become obvious when creating in 3D.
However, unless we are into Computer Aided Manufacture (CAM), we still need to produce paper drawings. These need to have a number of views, each complete with annotations and dimensioning to precisely define the object for the builder or manufacturer.
The following text will provide step-by-step instructions on how to make use of Sheet Models to document a supplied 3D model. Of course, the same general process can be applied to any model of our own.
Models
Documentation of designs has suddenly become much easier with the introduction of MicroStation V8. MicroStation now supports Models, including Sheet models. Now the drawing process is even easier than producing the original design model. Since this concept is fairly new to MicroStation, a little explanation is appropriate.
Models in DGNs are sets of Design Elements (such as lines etc.) that are unique to that model. A single DGN may have many Models, but only one Model can be active at any time. There are Design and Sheet type models, with Design models containing the actual designs and Sheet models the "paper" drawings.
In other words, Sheet models are used to compose the final drawing, mostly from elements referenced from the Design model(s). Annotations and dimension elements are placed in this Sheet model, along with borders (usually referenced), title blocks (maybe cells) etc. The actual printouts are created from Sheet models.
The First Step
Files for the following examples are available for immediate download. They are "zipped" into TentFrame.ZIP, which will expand to create Tent Frame.dgn, along with a cell Library and a couple of border DGN’s. Only the DGN’s are needed for the following examples, but the cell library may be interesting to experiment with. The sample design model is of a set of tubular steel demountable framework components for a hire company party tent. This model was chosen to be complex enough to require multiple views, but simple enough to complete the exercises fairly quickly. A rendering of the completed frame is shown below, the model for which is included in Tent Frame.dgn.
We will start by downloading TentFrame.zip and expanding it into any convenient folder. If you would prefer to use the following instructions to create drawings from your own model, skip straight to "Creating a Sheet Model"; otherwise we will start by examining the supplied Tent Frame.dgn.
The Supplied 3D DGN File
Assuming that you have Tent Frame.dgn already unzipped:
- Start MicroStation V8 and open Tent Frame.dgn. At this stage, you will find only two view groups available from the View Group option menu (usually docked on the bottom-left of the screen). Each of these view groups opens its own model.
- Choose the Assembly Views view group.
- A rendered view of the complete frame assembly opens. This was created from appropriately rotated and accurately placed cells of a number of sub-assemblies, which in turn were created from the design model. This model is included to provide an overview of the design.
- Window in on details of the assembled frame and dynamically rotate the view to examine the design and familiarise yourself with it. There is a saved view named "Perspective" to restore the view if desired.
- Choose the Model Views view group, window in on the various components and sub-assemblies. Try turning on Constructions in the View Attributes dialog and noting the construction class elements used to create the 35 and 40mm rectangular hollow sections etc.
Hint: When selecting the view for dynamic rotation, manually snap to a keypoint on the model and accept this as a point to rotate about.
The Model model contains only the components and the sub-assemblies; the Assembly model has copies of the sub-assemblies in sufficient number to construct a complete frame assembly. For example, there is only one horizontal frame in the Model, but there are seven of them in the Assembly.
The DGN was created with metric units, but this can be changed to feet and inches under Settings > Design File without any of the geometry changing actual size.
