So, you want to know how to convert your paper or mylar drawings into 3D models. One word: carefully. But before we get into that let’s look at the reasons for converting.
Reasons for Converting 2D to 3D
There are many companies who have legacy 2D paper drawings or mylar drawings that are still relevant for maintenance and redesign. For instance, aerospace companies need to maintain their drawings for the life of the aircraft, which can be as long as 20 to 30 years, in some cases.
Manufacturing and parts companies need to maintain machinery and repair parts for older equipment.
Companies that generate electricity and water power, as well as railways, and the military all have equipment that can have many years of life, requiring maintenance, parts and occasional redesigning.
Many of these industries have engineering drawings that began life in the days of the 2D CAD. But, today, 3D is the design standard, so these industries and others find it necessary to convert older drawings to newer standards. 3D models are much easier to work with, enabling the reverse engineering that often needs to be done in order to bring complicated machinery up to current requirements.
But, conversion from older paper and mylar to 3D models can be a tricky proposition. That’s why we cautioned at the beginning of this article that it must be done carefully.
Paper drawings can become stained, torn, folded and wrinkled over the years, making it difficult, if not impossible to recreate totally accurate dimensions from scanned images of the originals.
Over Mylar drawings can yellow, shrink and warp, causing distortions in the allowable tolerances. Adding to this problem is the fact that the distortion can vary over the length and width of a mylar drawing. This means that at one end of the drawing the distortion may be very small, while at the other end it can be much larger, based on the varying conditions under which the drawing was stored. When this happens, tolerances become disproportional, and cannot be easily corrected.
These issues can create problems for the in-house CAD team whose main focus is the creation of new designs.
In-House CAD Team Disconnect
It’s not that the in-house staff can’t do the conversions. The problem is the time commitment required for accurate conversion from 2D drawings to 3D models.
In order for any business to be successful and profitable, the focus must be on the future. In-house CAD and engineering teams are rightly focused on next year’s model or the year after that. Taking time from their forward-looking focus to created models for repair parts for machinery that is many years old takes away from a business’s forward drive.