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Showing posts from February, 2025

Using Microwave Heating to Locally Anneal CNT-Coated FDM Prints

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The CNT coating between the layers is heated with microwaves to locally anneal. (Credit: Sweeney et al., Science Adv., 2017) Layer adhesion is one of the weak points with FDM 3D printing, with annealing often recommended as a post-processing step. An interestingly creative method for this was published in  Science Advances back in 2017, featuring the work of researchers at Texas A&M University and citing previous work by other teams. In the paper by [Charles B. Sweeney] et al, they describe how they coated PLA filament with carbon nanotubes (CNTs), resulting in this CNT being distributed primarily between the individual layers of polymer. This is useful because CNTs are quite sensitive to microwave radiation, resulting in the conversion to thermal energy, i.e. heat. Compared to traditional annealing where the entire part is placed into an oven or similar, this microwave-based heating – or locally induced RF (LIRF) as they call this method – localizes the heat to the inter...

Could Non-Planar Infill Improve The Strength Of Your 3D Prints?

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When you’re spitting out G-Code for a 3D print, you can pick all kinds of infill settings. You can choose the pattern, and the percentage… but the vast majority of slicers all have one thing in common. They all print layer by layer, infill and all. What if there was another way? There’s been a lot of chatter in the 3D printing world about the potential of non-planar prints. Following this theme, [TenTech] has developed a system for non-planar infill . This is where the infill design is modulated with sinusoidal waves in the Z axis, such that it forms a somewhat continuous bond between what would otherwise be totally seperate layers of the print. This is intended to create a part that is stronger in the Z direction—historically a weakness of layer-by-layer FDM parts. Files are on Github for the curious, and currently, it only works with Prusaslicer. Ultimately, it’s interesting work, and we can’t wait to see where it goes next. What we really need is a comprehensive and scientific t...

Taking A $15 Casio F91W 5,000 Meters Underwater

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When considering our favorite spy movies and kin that involve deep-sea diving, we’d generally expect to see some high-end watch that costs thousands of dollars and is specially engineered to withstand the immense pressures kilometers below the ocean’s surface. Yet what about a humble Casio F91W that can be bought for about $15 if it’s the genuine article and not one of the millions of fakes? Over at the  Watches of Espionage site they figured that they’d dress up one of these famous watches to give it the best possible shot at surviving the crushing pressures at a depth of 5 km . The actual modification to the F91W was pretty mild, involving nothing but a ‘hydro-mod’ whereby oil is used to replace the air inside the watch case. Since oil is incompressible, nothing bad should happen to the watch. Theoretically at least. The Watch-Under-Test (WUT) was strapped to a US Navy’s CURV 21 remotely operated vehicle and dunked into the ocean before starting its descend into the inky darkn...

RedBox In The 80s: Meet The VHS Vending Behemoth

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Redbox was a company with a moderately interesting business model—it let you rent DVDs from automated kiosks. It’s an idea so simple it’s almost surprising it didn’t appear sooner. Only, it did—all the way back in the VHS age! Meet the Video Vendor. YouTuber [SpaceTime Junction] was able to track down one of these rare machines, which apparently formerly served an Ohio rental outlet called Kohnen’s. It’s a monstrous thing that stands taller and about three times wider than traditional vending machines, and it could hold up to 320 tapes in its robotic magazine. It’s got lashings of woodgrain, a green-on-black CRT, and the beautiful kind of clicky keys that went away after the 1980s. [SpaceTime Junction] has a bunch of videos up on the machine, and you even get to see it powered up.  It’s a little difficult to see what’s going on, because the machine is something like nine feet wide and it’s all shot in vertical video. There isn’t a whole lot of content on these obscurities out ...