Author: Navarre Bartz

276 Articles

A dark walnut table sits in the sun in what appears to be a field. Voids in the natural wood slab have been filled with shiny bronze, and a bundle of copper wire sits upon the edge of the table in a jaunty artistic fashion.

A Different Take On The River Table Does It In Bronze

February 28, 2025 by 6 Comments

River tables are something we’ve heard decried as a passé, but we’re still seeing some interesting variations on the technique. Take this example done with bronze instead of epoxy.

Starting with two beautiful slabs of walnut, [Burls Art] decided that instead of cutting them up to make guitars he would turn his attention to a river table to keep them more intact. Given the price of copper and difficulty in casting it, he decided to trim the live edges to make a more narrow “river” to work with for the project.

Since molten copper is quite toasty and wood likes to catch on fire, he wisely did a rough finish of the table before making silicone plugs of the voids instead of pouring metal directly. The silicone plugs were then used to make sand casting molds, and a series of casting trials moving from copper to bronze finally yielded usable pieces for the table. In case that all seems too simple, there were then several days of milling and sanding to get the bronze and walnut level and smooth with each other. The amount of attention to detail and plain old elbow grease in this project is impressive.

We’ve seen some other interesting mix-ups of the live edge and epoxy formula like a seascape night light or this river table with embedded neon. And if you’re looking to get into casting, why not start small in the microwave?

Continue reading “A Different Take On The River Table Does It In Bronze” →

A blue-gloved hand holds a glass plate with a small off-white rectangular prism approximately one quarter the area of a fingernail in cross-section.

AI Helps Researchers Discover New Structural Materials

February 27, 2025 by 18 Comments

Nanostructured metamaterials have shown a lot of promise in what they can do in the lab, but often have fatal stress concentration factors that limit their applications. Researchers have now found a strong, lightweight nanostructured carbon. [via BGR]

Using a multi-objective Bayesian optimization (MBO) algorithm trained on finite element analysis (FEA) datasets to identify the best candidate nanostructures, the researchers then brought the theoretical material to life with 2 photon polymerization (2PP) photolithography. The resulting “carbon nanolattices achieve the compressive strength of carbon steels (180–360 MPa) with the density of Styrofoam (125–215 kg m−3) which exceeds the specific strengths of equivalent low-density materials by over an order of magnitude.”

While you probably shouldn’t start getting investors for your space elevator startup just yet, lighter materials like this are promising for a lot of applications, most notably more conventional aviation where fuel (or energy) prices are a big constraint on operations. As with any lab results, more work is needed until we see this in the real world, but it is nice to know that superalloys and composites aren’t the end of the road for strong and lightweight materials.

We’ve seen AI help identify battery materials already and this seems to be one avenue where generative AI isn’t just about making embarrassing photos or making us less intelligent.

A blue and white, 3D printed rose sits on a black surface with a fuzzy tan background behind it.

Thermorphs: Self-Folding 3D Prints

February 27, 2025 by 3 Comments

Prints separating from the build plate or warping when you don’t want them to is a headache for the additive manufacturer. [CNC Kitchen] walks us through a technique to use that warping to our advantage.

Based on a paper by researchers at the Morphing Matter Lab at UC Berkeley, [CNC Kitchen] wanted to try making 3D printed objects that could self-assemble when placed in hot water. Similar to a bimetal strip that you find in simple thermostats, the technique takes advantage of the stresses baked into the print and how they can relax when reaching the glass transition temperature of the polymer. By printing joints with PLA and TPU layers, you can guide the deformation in the direction you wish, and further tune the amount of stress in the part by changing the print speed of different sections.

[CNC Kitchen] found that Hilbert curve infill slows the printer down sufficiently to create relatively stress-free sections of a print to create flat sections which is an improvement over the original researchers’ all TPU flat sections with respect to rigidity. We’ve covered how to reduce warping in 3D prints, but now we can use those techniques in reverse to design self-assembling structures. These parts, being thermoplastic, can also be heated, reformed, and then exhibit shape memory when placed back into hot water. It’s very experimental, but we’re curious to see what sort of practical or artistic projects could be unlocked with this technique.

We’ve seen a few other interesting techniques with folded objects like laser cutter origami, some flat-to-folded 3D prints that might be interesting to try with this technique, and also folded hybrid mechanisms made with laser cutting and 3D printing.

Continue reading “Thermorphs: Self-Folding 3D Prints” →

A man in a t-shirt and sport coat sits behind a table upon which are a small, black air fryer and a larger pale green model that looks more futuristic. Behind him is a black set of cube shelves (possibly IKEA Kallax) with different colored interiors lit and holding various bits of vintage technology equipment like landline phones and HiFi setups.

How Do Air Fryers Work?

February 27, 2025 by 63 Comments

Air fryers are the new hotness in the kitchen, but are they actually any different than a convection oven? [Technology Connections] walks us through the design of these countertop appliances to find out.

If you like your fries and chicken crispy instead of soggy, you traditionally had to eat out or spend the better part of an hour waiting on your food to cook to a crisp in the oven. Convection ovens significantly speed up this process by moving the air about and keeping the food from sucking most of the heat out of the stagnant layer just next to it.

It turns out that most air fryers are just a coil stove element and a fan placed above a basket which is just a fancy re-arrangement of the parts of a toaster or convection oven. The magic sauce here is the small size and the fact you don’t have to futz with pulling a hot wire basket out of your toaster or larger convection oven. The small size does give you a pretty big advantage in preheating and precise application of heat to the food for smaller batch sizes, but if you already have a convection oven, the advantages might not outweigh the additional space and cost of yet another kitchen gadget. We appreciate the sacrifice of eating “a lot of french fries” to test the differences between brands and conventional convection ovens for our edification.

If you’re looking for a way to make cookies faster instead of fries, how about this hack using a microwave and a heat gun? Or maybe it’s better to redesign the food instead of the appliance like this ramen in an edible package or these origami noodles.

Continue reading “How Do Air Fryers Work?” →

An overhead shot of a parking lot. A road with cars parked along it is on the right hand side of the image. The top center shows a drilling rig on tracks drilling at a slight angle into the ground. Many different semi trailers dot the parking along with several different pallets of construction supplies. An excavator and skylift/forklift are also at work in the lot.

District Heat Pump Systems Save Money And Gas Utilities

February 26, 2025 by 50 Comments

Ground-source heat pump systems are one of the most efficient ways to do climate control, but digging the wells can be prohibitively expensive for the individual citizen. What if you could do it at a larger scale?

Starting with a pilot to serve 37 commercial and residential buildings in Framingham, MA, Eversource is using its experience with natural gas drilling and pipe to serve up a lower carbon way to heat and cool this neighborhood. While district heating via geothermal has precedents elsewhere in the country, Boise is a notable example, it has remained a somewhat niche technology. Once networked, excess heat from one location can be used elsewhere in the system, like data centers or industrial facilities being used to heat homes in the winter.

As gas utilities look to transition away from fossil fuels, their existing knowledge base is a perfect fit for geothermal, but there are some regulatory hurdles. Six states have passed laws allowing natural gas utilities to expand beyond just gas, and bills have been filed in six more. This will likely accelerate with the formation of the Utility Networked Geothermal Collaborative which includes many utilities including giants like Dominion Energy who are looking to expand their energy portfolios.

If you want to dig more into district heating systems or geothermal energy, we’ve covered cogeneration from power plants to serve up the heat instead, doing it with wind, or even using old coal mines for geothermal heat.

A bright yellow crew cab pickup is on an unpaved area with snow-capped mountains in the distance. In its bed is a matching camper shell which is somewhat trapezoidal with a smaller semicircular section that can pull out to lengthen the sleeping space of the camper. At the top of the image it says, "Sleeps Two!" with an arrow pointing to the camper shell.

Want A Truck With A Short Bed And A Long Camper Shell?

February 26, 2025 by 37 Comments

Camper shells are a time-honored piece of truck gear, but with modern trucks having increasingly vestigial beds, the length of your overnight abode has increasingly shrunk as well. To combat this problem, [Ed’s Garage] built a camper shell that extends once you’ve arrived at your campsite.

[Ed] wanted to keep things relatively low profile while still tall enough to sit up in for convenience, leading to a small bit of the shell peeking over the truck’s roof. To keep the cold Canadian winter out, attention was paid to proper weather sealing around the sliding portion of the shell so that it stays warm and dry inside.

While this would work on any truck, the mains power plugs in the bed of some modern trucks mean that certain glamping conveniences like a heater and projector can be easily powered while you’re in camp. We get to see the camper shell in action at the end of the video where the pros and cons of having your sleeping space also being your storage while en route become apparent.

If you’re looking for something a little less conventional for your camping experience, how about this solar camper or this retro bike camper?

Continue reading “Want A Truck With A Short Bed And A Long Camper Shell?” →

A dark warehouse contains a number of large blocky objects. A Tesla Model 3 sedan sits in the center with flames underneath and curling up the side away from the camera. A firefighter on the left side attempts to put out the fire with a fire hose.

UL Investigates The Best Way To Fight EV Fires

February 26, 2025 by 50 Comments

While electric vehicles (EVs) are generally less likely to catch fire than their internal combustion counterparts, it does still happen, and firefighters need to be ready. Accordingly, the UL Research Institute is working with reverse engineering experts Munro & Associates to characterize EV fires and find the best way to fight them.

There is currently some debate in the firefighting community over whether it’s better to try to put an EV battery fire out with water or to just let it burn. Research like this means the decision doesn’t have to fall on only anecdotal evidence. Anyone who’s worked in a lab will recognize the mix of exceedingly expensive equipment next to the borderline sketchy rigged up hacks on display, in this case the super nice thermal imagers and a “turkey burner on steroids.” The video goes through some discussion of the previous results with a Chevy Bolt, Hyundai Kona, Ford Mustang Mach E, and then we get to see them light up a Tesla Model 3. This is definitely one you shouldn’t try at home!

While the massive battery banks in modern EVs can pose unique challenges in the event of an accident, that doesn’t mean they can’t be repurposed to backup your own home.

Continue reading “UL Investigates The Best Way To Fight EV Fires” →