Why Bother Replacing 2D Drawings with 3D Models?

by Madhavi Ramesh

Yes, why would you want to replace 2D drawings? Clearly, 2D Drawings have their own advantages. But there are disadvantages to 2D Drawings. Let’s consider a couple of scenarios.

One, the drawing gets recreated possibly many times in most companies for various reasons. This amounts to the additional duplicated effort required in creating a 2D drawing from a 3D model. The second scenario is the use of pen and paper based verification of the design intent. Traditionally, different marker pens have been used to “markup” the drawing to communicate the changes needed. These changes are lost when the design iterates. But what if you had a mechanism to track who said what and when was it said? Wouldn’t be that valuable? It is also a step towards replacing 2D drawings with intelligent 3D models.

A first step to replacing a 2D drawing is to ensure that the design intent present on the drawing is represented accurately and unambiguously in the 3D model. Typically, the design intent is captured in PTC Creo or other CAD tools such as CATIA V5.

The picture below shows design intent being captured in PTC Creo Parametric:

The next step is to publish the design intent for use by the downstream users. PTC Creo View provides a mechanism to publish most of the design intent from PTC Creo Parametric and CATIA V5 into the PVZ format (viewable file). The software allows for selective publishing of geometry, dimensions, tolerances and view states from PTC Creo Parametric or capture states from CATIA V5. This means that you can protect the intellectual property by restricting the information contained in the viewable file. The picture below shows the design intent published from PTC Creo Parametric.

Once the published 3D model is available, the downstream user can easily interact and interrogate the data on demand. PTC Creo View has an intuitive interface to work with model based design data. The Microsoft-like user interface makes it easier for users to find and use program capabilities. The overall look and feel of the applications has been streamlined. The user cannot only visualize and but also take quick measurements. The picture below shows the viewable file accessed from within PTC Creo View.

Design Checking
Moving to 3D also allows you to take advantage of many more capabilities within the PTC Creo View suite of products. One such area is the design checking process. Historically, the design checker role within the company would review the 2D drawing and call out any discrepancies. A set of colored markup pens are used to highlight the problem areas. This redlining of drawings has traditionally been a pen and paper-based process.

But with PTC Creo View Design Check, the markup/redlining process can now be very efficient as every critical dimension and tolerance present in the model can be digitally verified for accuracy and unambiguous definition. Any discrepancies found can be captured as markups in the tool for later retrieval. One of the significant capabilities of this tool is the storage, management and the traceability of these markups. As the design iterates, all the knowledge that went into the decision making is easily available at any point in time. Also, the visual dashboard provides a quick status of the design in terms of who said what, when it was said. It also demonstrates the “why” as shown in the picture below.

This post covered the some of the considerations for replacing 2D Drawings. While the idea of replacing of 2D Drawings sounds good, there are a number of barriers to the wholesale adoption of 3D models across the enterprise. Some of them include the Cultural readiness, Technology readiness, Contractual obligations, etc. Replacing 2D Drawings is a journey and more & more companies are embarking on this journey. A question: Are you considering to replace 2D Drawings at your company? Let me know your thoughts.