3D scanning is expected to reach $53.3 billion as a market in 2025, but are you on top of it? More people in more fields are how to 3D scan an object to improve their data and quality assurance methods.
Make sure you don’t get left behind if you are in the architecture, engineering, and construction (AEC), additive and subtractive machining, assembly, restoration, or a dozen other industries.
Keep reading for a quick guide on 3D scanning that you can use today.
Step 1: Prepare the Surface
First things first, you have to prepare your surface. It will be impossible to image an object if the surfaces are scanning are reflective or transparent.
Like prepping someone’s skin before they go on TV, if the object you are scanning is too shiny it disrupts the accuracy of the image. Since 3D scanning is all about quality and accuracy, you don’t want mistakes.
Matte powder sprays are available which take the shine out of most surfaces, and best of all they’re usually temporary. For transparent items, they’ll have to be “painted” in a matte color suitable for your scanner to read accurately.
Step 2: Say Cheese
Only step 2, and we’re already scanning? Yes, because taking images, or using a laser or x-ray imager to create a cloud of data isn’t enough.
Also, we complete this step in various ways, as there are different kinds of scanning machines for different purposes. Some processes are actually two or three different technologies merged together. Some might use photogrammetry or a laser 3D scanner, or a combination of the two.
Whatever the device or method you use to scan, the actual scanning will differ by the proprietary method of the scanning device. Also to consider is the type of scanning the device does.
As it sounds, a photogrammetrical scan takes pictures. Fine for an iPad, but an iPad can’t quite handle a project the size of an airliner, or the tolerances required. That’s where something like a laser scanner comes into play.
Step 3: Making a Mesh of Things
After you scan using the device, it makes the scan into what we call a “mesh” file. Because the scanning device is only scanning the surface of an object, it doesn’t create a solid file for engineers to manipulate or compare yet.
This is like your DSLR or other professional camera taking a picture in a “RAW” format. It is a map of pixels of varying color information 1 for 1 on the sensor of the camera. After you have that, you take the mesh into the software to render it, and it is usually exported as a converted file type.
The same is happening with the mesh file. Because the scan makes millions of points of raw data, it’s a massive file that isn’t very practical for editing purposes. This step of refinement is crucial for comparing the scanned “as-built” object to the master “as-designed” object.
Once the mesh has been reduced and refined, we can make it into a workable “solid” CAD file.
Step 4: Surface Extraction
Your mesh is now imported into your CAD program, and you’re ready to go! Well, as soon as you’ve mapped the surface. This is the conversion part of things we talked about before, and there are basically three ways to do it.
But why do we have to do this, isn’t that what the scan is for? The scan is millions of points of data and not a contiguous surface. What you’re doing in this phase is stitching those points together.
Manual surfacing is as it sounds: you have to tell the program every detail of the surface of the object. This is performed by using planes and merging them together. This is often the fastest and most accurate surfacing method, unless it’s a complex curved shape.
In Semi-Automatic surfacing, you are still generating planes, but you often have a kind of “brush” tool to merge those planes together in a softer way. This will rough out sharper transitions you generally get with manual surfacing. This tends to be the most accurate for complex curved surfaces.
By far the fastest method and most hands-free would be the automatic surfacing method. It isn’t as accurate, but the object must be scanned very accurately to begin with. This is best used for a jig that exists as a physical object that you want to make duplicates of, or factory QA tests.
Step 5: Replicate
We aren’t quite at the stage of atomic assembly as in Star Trek, but we’re getting there. Once you have your surface CAD file extracted from the mesh, you can edit or compare it to another solid surface for inspection. If your intention is to 3D print from here, you can yell “replicate” to a 3D printer and make a model of any scalable size needed that the printer can handle.
It’s been a long road, but we’re finally there. A replicated part is in your hands, or you’re inspecting the “as-built” part, comparing it to the “as-designed” one.
It sounds like a long process until now, but printing takes the longest. If you working factories or architecture, this stage is not as important. Although, if you are an architect studying an ancient ruin or historical structure, you likely have a need for accurate models.
Taking things from digital to physical is an obvious industry move to watch for in a society like ours that craves endless prototyping. 3D printing has been a hugely disruptive technology in this regard.
How to 3D Scan an Object: Over and Out
In a digital world, many people haven’t gotten past the 2D scanners from yesteryear and taken the leap to 3D. It is no less critical to take something in the physical world and bring it into the digital one.
We hope you didn’t only enjoy this article on how to 3D scan an object, but that you were able to find a good use for it. Be it for convincing your team to consider applications for 3D scanning, or for helping you to decide on which 3D scanner to buy or use.