3D Printing and Scanning - Watch Case Design & The Incredibles!

<a href="../../index.html"> ## _**back home please!!**_ </a> ___ ## Hey all! ___ ## 3D Printing ___ Personally, one of the things that attracts me most to 3D printing is its utility in prototyping. So in thinking about what would make sense to create through additive manufacturing, one of the first things that came to mind was a design for the case of my final project. Given that my final project has the ultimate goal of ending up a wearable, I figured that one of the things I will certainly want to have sorted out later is what exactly the body will look like when it's on your wrist! As such, I began designing. For the initial iteration of what my case may look like, I wanted to draw some inspiration from the watch that I wear every day. So I laid out an appropriately sized photo of my watch and began working on a sketch for the shape of the main case. As you can see below, one of the things that I aimed to improve from the design of my watch's case was the layout of the lugs - though I like the quirky vintage styling, I figure that I would like my watch to have a slightly more streamlined design to its lugs in order to update it from Vostok's 420 case design. However, the rough size of the dial remained the same, as the trend towards 42mm dials on watches is a trend I'm personally not a fan of. Once the sketch was done, I was able to slice it into quarters so I could safely work on and then replicate the designs of the lugs to ensure the springbars fit perfectly. <img src="img/initial_design.jpg"></img> <img src="img/quarter_design.jpg"></img> From here, I wanted to round out the design of the lugs so that the watch would sit snug on the wrist, and the curve of the lugs would be comfortable to wear. <img src="img/lug_design.jpg"></img> And once that was all finished up, I took the opportunity to round off the design so the lugs were more seamlessly integrated into the main case. And last of all was to include the holes for the springbars! Once it was properly sized and aligned on the one quarter of the case, I mirrored that bad boy to create the full body! Last but not least, I went ahead and added a bottom to the hollowed-out face of the watch, and after much trial and error, the design was complete. All ready to 3D print! <img src="img/full_design.jpg"></img> <video width="600" autoplay loop muted> <source src="img/printing.webm"> </video> After some serious wrestling with the printer I was using, I finally got the printhead to stop clogging, and while I was at it, troubleshot some issues I'd been having with bed adhesion and support printing. With the final product pulled out of the printer, it was time to see if it could actually fit standard 18mm springbars and straps (because to be fair, having a watch you can't put your own strap on is demonstrably less useful than having no watch at all). I was concerned by the appearance of the springbar holes, which seemed large enough in neither diameter nor depth. A look of terror crossed my face as I thought that the precision of this 3D printer just might not be able to accurately handle a feature that small. But a pleasant surprise awaited when the springbars fit in after only having one fly across the room. <img src="img/bare_print.jpg"></img> <img src="img/springbars.jpg"></img> And with great anticipation, I threaded in the strap and fastened it to my wrist! <img src="img/wrist.jpg"></img> I'm fairly happy with how it is looking for a first prototype, but there are certainly a few limitations that I will be noting for future case designs. First, the 3D printer's resolution (in this case bottlenecked mostly by layer height) is not sufficient to resolve the smaller and more shallow curves on the case, making it somewhat sharper than I'd anticipated. Additionally, due to the nature of the first few layers of the print, it seems quite difficult even with support material to create a curvature on the case's bottom to mold to the wrist. As a result, if I end up prototyping further with 3D printing, I plan to try out the Sindoh printers, both for improved resolution and for the convenience of dissolvable supports in printing more complex structures. ___ ## 3D Scanning ___ One of my favorites among the many objects that are scattered around my room is this adorable little bobblehead of Edna Mode from The Incredibles. <img src="img/edna.jpg"></img> So naturally, I wanted to 3D scan her for this assignment! That being said, given that she is a bobblehead, she does have a tendency to bobble unprovoked, which could possibly present an issue in trying to get a clean model. My first attempts with the 3D scanner in the EDS were quite frustrating, so ultimately I ended up deciding on using an app to make my scan. First I tried out an app called Trnio, which had trouble capturing all sides of the model as its tracking was entirely gyroscope-based. As such, every little calibration error would compound, and ultimately though it was just a mesh of the front, the following was the best I could get it to produce: <img src="img/edna_bad_0.jpg"></img> <img src="img/edna_bad_1.jpg"></img> However, a little more digging around led me to the app Qlone, which uses a QR-like mat similar to those used in AR apps to track the position and size of the surface. This did away with many of the inconsistencies I was experiencing in the other app, and also allowed me to put the object on a turntable while I rotated it to capture images. Most certainly a better experience despite some minor nitpicks I had. Here is the final product I captured with it! <img src="img/spin.gif"></img> ___ ## Construction Files <a href="src/watch_case_18mm.stl", target="_blank" download> __watch_case_18mm.stl__ </a> ___ <a href="../../index.html"> ## _**back home please!!**_ </a>