Scan to CAD Process Preserves Legacy Paper Drawings
One of the problems when referring to a CAD drawing that was made before the “digital age” is that it may be handed to you as an old set of mylars, vellums or blueprints to work from. Short of starting from scratch by recreating the paper drawing in CAD, what can you do? Scan to CAD is the process that enables you to get these old drawings into a digital format for use in your CAD program.
Scan to CAD may sound like a single process, but it is actually a series of processes that start with scanning the original drawing on a good quality large format scanner. As you know, if you read our blog regularly, we’re partial to Contex Scanners.
The default file format for large format scanner output is a .tif file, which can be easily imported into nearly any CAD program. The only caveat is that a .tif file is a raster image and CAD programs use vector images. So, while you can draw on top of the .tif, you can’t edit it, alter it, or add to it. For some operations, this may be enough, but if you need more usability, then the raster file needs to be converted to vector.
Raster and Vector
What is the difference between a raster and a vector file? A raster file is an image…a picture, if you will, while a vector file consists of lines, curves, fonts, symbols and other highly manipulate-able objects. You can move these objects, change their size, rotate them, twist them, turn them or color them. You can’t do that with a picture.
Converting drawings to vector files is not easy. One of the main advantages of Scan to CAD outsourcing is to get the job done by experienced professionals, who start with highly accurate scanners and proceed immediately to the best method of raster to vector conversion for the type of drawing you have. While this may cost you a couple of hundred dollars per drawing, the cost of re-drawing from scratch is much higher.
A professional Scan to CAD service will also be able to save your drawings in whatever format you need — AutoCAD, Microstation, or even 3D CATIA.
So, if you have legacy paper or mylar drawings that are taking up space, deteriorating with age, hard to locate, and that need to be preserved and accessed by your CAD software, consider outsourcing your Scan to CAD requirements. Companies like CAD CAM Services specialize in fast, accurate Paper-to-CAD services and are even certified by the US Department of Defense for CAD conversion work.
Scan In-House, Send R2V Out
Alternatively, some companies prefer to do the scanning in-house, as needed and send the .tif files electronically to a conversion service. While this means that you will need an in-house scanner, many companies find that owning a large format scanner can be advantageous, especially with the easy availability and fast delivery of today’s low cost, high accuracy scanners. Scanning in-house saves on the shipping costs associated with sending paper drawings out, while still enabling the professional touch required for raster to vector conversion.
But what about raster to vector conversion software? If we’re going to scan in-house can’t we convert in-house, too?
We get asked this question all the time. And, yes, we even sell raster to vector software. But, our experience has been that no matter how good the raster to vector software is (and there is some very good software available), it still takes manual tweaking to get a detailed, completely accurate, professional drawing of the type that is required in applications requiring high-tolerances (aerospace, manufacturing, etc.) This is because the most r2v software is designed for use by anyone who needs to restore, update or revise a raster or vector drawing, and is designed to work over a wide range of applications – GIS, cadastral, aerial and satellite image processing, architecture, engineering, schematics and others.
When tolerances are critical, or when converting to a 3D application, we recommend relying on a professional conversion service.
Scan-to-CAD is a valuable, multi-step process that is used to convert legacy paper drawings to useable 2D or 3D CAD files. The entire process can be done by an outsource Scanning and CAD Conversion company, or you may decide to do the scanning in the house and send only the .tif files to the outsource company for conversion. Either way, the professional touch can go a long way to improving the process.