Author: Navarre Bartz

292 Articles

A green hat with a grey zipper is partially opened revealing the grey mesh inside. It is held by two hands manipulating the zipper. The picture is inside a red circle overlaid on top of a tinted image of a workshop. A red line points to an image of a woman looking to the right wearing the green baseball cap.

Bring Your Reusable Grocery Bag On Your Head

July 10, 2024 by 60 Comments

After decades of taking plastic bags for granted, some places now charge for them to help offset some of the environmental damage they cause. If you have a tendency to forget your reusable bags at home but love to wear hats, [Simone Giertz] has the bag hat for you.

Having conquered everything from making the first Tesla pickup to a tambour puzzle table, a hat that can turn into a grocery bag seems like a relatively easy challenge. It was not. One thing that [Giertz] observes early in the process is that fabric is a much less “honest” material since it can move in ways that many of the other materials she works with cannot, like glass or wood.

As with any good project, there are numerous iterations of the bag hat, mostly due to trying to balance the two distinct functions of bag and hat without overly-compromising either. In the end, the hat features a zipper down the center from ear to ear that opens up into a mesh grocery bag. The adjustable loop of the hat does double duty as the bag handle.

If you’d like to build your own sewing machine for projects like this, maybe you should find out how they work. If you’d rather just get on with the sewing bit, we can help you with that too.

Continue reading “Bring Your Reusable Grocery Bag On Your Head” →

A man in a red plaid shirt draped over an olive t-shirt holds sandpaper in one hand an an aluminum tube filled with white beads in the other over a wooden table.

Activated Alumina For Desiccating Your Filament

June 27, 2024 by 23 Comments

When you first unwrap a shiny new roll of filament for your FDM printer, it typically has a bag of silica gel inside. While great for keeping costs low on the manufacturing side, is silica gel the best solution to keep your filament dry at home?

Frustrated with the consumable nature and fussy handling of silica gel beads, [Build It Make It] sought a more permanent way to keep his filament dry. Already familiar with activated alumina beads, he crafted a desiccant cylinder that can be popped into the oven all at once instead of all that tedious mucking about with emptying and refilling plastic capsules.

A length of aluminum intake pipe, some high temperature epoxy, and aluminum mesh are all combined to make a simple, sealed cylinder. During the process, he found that using a syringe filled with the epoxy led to a much more precise application to the aluminum cylinder, so he recommends starting out that way if you make these for yourself.

We suspect something with a less permanent attachment at one end would let you periodically swap out the beads if you wanted to try this hack with the silica beads you already had. Perhaps some kind of threaded pipe fitting? If you want a more active dryer, try making one with a Peltier. If you want to know just how dry your filament is getting, you could also put in a sensor. You might also wonder, do you really need to dry filament at all?

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Nine men of various ages and ethnicities stand in a very clean laboratory space. A number of large white cabinets with displays are on the left behind some white boards and there are wireless charging coils on a dark tablecloth in the foreground. In the back of the lab is a white Porsche Taycan.

Polyphase Wireless EV Fast Charging Moves Forward

June 21, 2024 by 85 Comments

While EV charging isn’t that tedious with a cable, for quick trips, being able to just park and have your car automatically charge would be more convenient. Researchers from Oak Ridge National Lab (ORNL) and VW have moved high-speed wireless EV charging one step closer to reality.

We’ve seen fast wireless EV chargers before, but what sets this system apart is the coil size (~0.2 m2 vs 2.0 m2) and the fact it was demonstrated on a functioning EV where previous attempts have been on the bench. According to the researchers, this was the first wireless transfer to a light duty vehicle at 270 kW. Industry standards currently only cover systems up to 20 kW.

The system uses a pair of polyphase electromagnetic coupling coils about 50 cm (19″) wide to transfer the power over a gap of approximately 13 cm (5″). Efficiency is stated at 95%, and that 270 kW would get most EVs capable of those charge rates a 50% bump in charge over ten minutes (assuming you’re in the lower part of your battery capacity where full speeds are available).

We’ve seen some in-road prototypes of wireless charging as well as some other interesting en route chargers like pantographs and slot car roads. We’ve got you covered if you’re wondering what the deal is with all those different plugs that EVs have too.

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Open Source Your Air Ride Suspension

June 19, 2024 by 8 Comments

Air ride suspensions have several advantages over typical arrangements, but retrofitting a system to a vehicle that didn’t come with it can get pricey fast, especially if you want to go beyond the basics. The Open Source Air Suspension Management Controller aims to give people a fully customizable system without the expense or limitations of commercial units.

The project started as an upgrade to a basic commercial system, so it assumes that you’re bringing your own “bags, tank, compressor, tubing and fittings.” The current board uses an Arduino Nano, but the next revision based on the ESP32 will allow for a wider feature set.

With a Bluetooth connection and Android app, you can control your ride height from a phone or integrated Android head unit. Currently, the app shows the pressure readings from all four corners and has controls for increasing or decreasing the pressure or airing all the way up or down to a given set point.

Want to know how air suspensions work? How about this LEGO model? If you want a suspension with active tuning for your bike, how about this Arduino-powered mod?

A rectangular box with a purple section sandwiched between two red sections sits on a black tabletop. The end of the box is open. Black and red wires run out of the back of the box to a breadboard.

Improving Wind Turbine Testing With A Better Air Source

June 17, 2024 by 16 Comments

When comparing the efficiency of different wind turbine blade designs, [AdamEnt] found using a hair dryer wasn’t the best tool for the job. Enter his new 3D-printed wind tunnel.

After several prototypes, [AdamEnt] decided on a design that exploits slicer infill to create a flow straightener without having to do any tedious modeling of a lattice. Combined with a box on both ends of the straightener to constrain the flow, he has a more controllable air source with laminar instead of turbulent flow for testing his wind turbines.

The BLDC motor driving the air is attached to a toroidal blade of MIT fame. We get a little bit of the math behind calculating wind turbine efficiency and see a quick test of a blade placed next to the outlet of the air source at the end of the video.

If you’re planning on building your own wind tunnel, we’ve covered a few. We’ve even seen one that goes up to Mach 20, although that probably wouldn’t be useful for wind turbine design!

Continue reading “Improving Wind Turbine Testing With A Better Air Source” →

Shipping Your Illicit Software On Launch Hardware

June 13, 2024 by 17 Comments

In the course of a career, you may run up against projects that get cancelled, especially those that are interesting, but deemed unprofitable in the eyes of the corporate overlords. Most people would move, but [Ron Avitzur] just couldn’t let it go.

In 1993, in the midst of the transition to PowerPC, [Avitzur]’s employer let him go as the project they were contracted to perform for Apple was canceled. He had been working on a graphing calculator to show off the capabilities of the new system. Finding his badge still allowed him access to the building, he “just kept showing up.”

[Avitzur] continued working until Apple Facilities caught onto his use of an abandoned office with another former contractor, [Greg Robbins], and their badges were removed from the system. Not the type to give up, they tailgated other engineers into the building to a different empty office to continue their work. (If you’ve read Kevin Mitnick‘s Ghost in the Wires, you’ll remember this is one of the most effective ways to gain unauthorized access to a building.)

We’ll let [Avitzur] tell you the rest, but suffice it to say, this story has a number of twists and turns to it. We suspect it certainly isn’t the typical way a piece of software gets included on the device from the factory.

Looking for more computing history? How about a short documentary on the Aiken computers, or a Hack Chat on how to preserve that history?

[Thanks to Stephen for the tip via the Retrocomputing Forum!]

A clipping of the "3D Printing & Modelling" skill tree. An arrow pointing up says "Advanced" and there are several hexagons for various skills on the page including blanks for writing in your own options and some of the more advanced skills like "Print in Nylon or ASA material"

Maker Skill Trees Help You Level Up Your Craft

June 11, 2024 by 12 Comments

Hacking and making are great fun due to their open ended nature, but being able to try anything can make the task of selecting your next project daunting. [Steph Piper] is here with her Maker Skill Trees to give you a map to leveling up your skills.

Featuring a grid of 73 hexagonal tiles per discipline, there’s plenty of inspiration for what to tackle next in your journey. The trees start with the basics at the bottom and progressively move up in difficulty as you move up the page. With over 50 trees to select from (so far), you can probably find something to help you become better at anything from 3D printing and modeling to entrepreneurship or woodworking.

Despite being spoiled for choice, if you’re disappointed there’s no tree for your particular interest (underwater basket weaving?), you can roll your own with the provided template and submit it for inclusion in the repository.

Want to get a jump on an AI Skill Tree? Try out these AI courses. Maybe you could use these to market yourself to potential employers or feel confident enough to strike out on your own?

[Thanks to Courtney for the tip!]

Continue reading “Maker Skill Trees Help You Level Up Your Craft” →