Generate Graph Paper — Complete with Jolly Wrencher

There’s a lot of talk about CAD software these days, and don’t get us wrong, they’re an essential tool of the trade. But for roughing out an idea, nothing tops paper and a pencil. Even the back of a cocktail napkin will do.

If you’re like us, at some point you may have had an engineering teacher force you to sketch your ideas out on paper, rather than in software. Or maybe you went to a university that required engineering students take a drawing/drafting class, where the first few weeks, you’re only allowed to use paper and pencil.

It may seem silly that in today’s age that one would choose to sketch an idea out by hand, but one simple drawing can communicate an idea quickly and easily – and that’s key. After all, the biggest part of engineering is communication.

If you’re a bit older you may remember a staple in every engineering office was the green graph paper – some people called it an “Engineer’s Notepad.” It’s basically perfect for jotting down an idea. Thick lined graph paper on the back of each page that lets the lines be visible on the front, without being distracting. It’s becoming harder and harder to find at your local office supply place, but if you search for “Ampad Engineering Pad” you’ll still find it. (There is also a “National” brand that this writer prefers.)

If you’re in a pinch, or don’t want to pay for a full pad, we found a wonderful alternative. This online graph paper generator will allow you to make your own graph paper, and even customize it to suit your needs. With things like multi-weight lines, and polar graphs and much more. The result is a PDF file you can download and keep for the future. Or if you’re a bit crafty, you can add your own logo in an vector-type editing  program such as Inkscape for free.

Still need some pointers on how to using this for project planning? [Steve] sets the standard for graph-paper project planning.

Shirt Printing With Freezer Paper

There’s a pretty good chance that you’ve wanted to add a graphic or design to a t-shirt some time in your life. There are certainly ways to do it but most of us don’t have silk screening equipment or a steady enough hand to have the end product look cool. Lucky for us, [UrbanThreads] has put together a stenciling tutorial for personalizing garments. The process is easy and inexpensive. The results are good, although it can be time-consuming if the pattern is intricate.

To get started, a black and white graphic is printed on a sheet of paper. The design is then taped to a sheet of the secret ingredient: freezer paper. The two sheets are then placed on a table with the freezer paper up. Since the freezer paper is semi transparent, the printed out design shows through. It’s now time to use an exacto knife and trace the design while cutting through the freezer paper. The two sheets are then removed from each other and the freezer paper is put wax-side-down on the garment and ironed into place. The wax melts and acts as a temporary adhesive to hold the stencil down. At this point, fabric paint can be sprayed or dabbed on with a brush (avoid brushing back and forth as it may lift the stencil). Once the paint is applied, the stencil is removed and the paint is allowed to dry. According to [UrbanThreads] the freezer paper doesn’t leave any wax or residue on the garment.

For more garment modding, check out t-shirt bleaching or get ambitious with this DIY screen printing setup.

Using The Sun To Beat The Heat

It’s practically May, and that means the sweltering heat of summer is nearly upon us. Soon you’ll be sitting outside somewhere, perhaps by a lake, or fishing from a canoe, or atop a blanket spread out on the grass at a music festival, all the while wishing you had built yourself a solar-powered personal air conditioner.

[Nords] created his from a large insulated beverage vessel. The imbibing spout offers a pre-made path to the depths of said vessel and the heart of this build, the ice water refrigerant. [Nords] fashioned a coil out of copper tubing to use as a heat exchanger and strapped it to the fan that performed best in a noise-benefit analysis.

A small USB-powered submersible pump moves the ice water up through the copper tubing. Both the pump and the fan run off of a 5V solar panel and are connected with a USB Y cable, eliminating the need for soldering. Even if you spend the summer inside, you could still find yourself uncomfortably warm. Provided you have access to ice, you could make this really cool desktop air conditioner.

[via Embedded Lab]

Crosswalk Pong Auf Deutschland

What is there to do in America while you’re waiting to cross the street at an intersection? Nothing; listen to that impatient clicking sound, and if you live in a busy city, pray you don’t get plowed into. In Germany however, pedestrians will now get to play Pong with the person on the other side.That’s right, as a means to encourage people to just hang in there and wait out the cycle instead of darting across against the light, design students [Sandro Engel] and [Holger Michel] came up with an entertaining incentive involving a potential conversation sparking duel with your impromptu counterpart across the street.

The first of these interactive cross-walk indicators was installed recently in Hildesheim, Germany, two years after the duo first designed them back in 2012. There was a little friction about installing the touch screen equipped modules initially, but after a proper redesign for functionality taking traffic science into account, the city authorities caved and allowed them to test the wings of their progressive idea on one city intersection so far. The mindset behind the invention of these indicators is part of a larger movement to make public spaces safer through means of fun and entertainment. Instead of threatening to punish those partaking in unsafe activity with fines, the notion is to positively enforce following rules by adding a level of play. While pedestrians have the right to walk, the screen shows how much time is left to make their away across, and for the duration that traffic is rolling through, the score will be kept for an individual game of pong for those on either side of the light.

Since the idea is generating some interest, the group of developers involved with the project have moved to promote their work (now branded as Actiwait) with an Indiegogo campaign. They hope to turn their invention into a full fledged product that will potentially be seen all over the world. Admittedly, it’d be charming to see this sort of technology transform our urban or residential environments with a touch of something that promotes friendly social interaction. Hopefully my faith in our worthiness to have nice things is warranted and we start seeing these here in America too. Nice work!

Check out this encounter with the street indicator here. The guy introducing the invention loses to the girl on the other side, but they share a high-five as they pass in the street:

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Triple Sensor Mailbox Alert Really Delivers

Messing with the U.S. Mail is not something we generally recommend. But if you build your own mailbox like [Bob] did, you stand a much better chance of doing what you want without throwing up any flags.

Speaking of throwing up flags, one of the coolest parts of this project is the toy mailbox inside the house that monitors the activity of the real box. When there is mail waiting, the flag on the toy mailbox goes up. Once [Bob] retrieves the mail, the flag goes back down automatically. A magnet in the real box’s flag prevents false alarms on the toy box provided the Flag Raised On Outgoing protocol is followed. Best of all, he built in some distress handling: If the mailbox door is left hanging open or the battery is low, the toy mailbox waves its flag up and down.

So, where do the three sensors come in? A magnetic reed switch on the wall of the real mailbox pairs with a magnet in the flag. To determine whether the door is open, [Bob] initially used another magnetic reed switch on the underside of the box. This didn’t work well in wet weather, so he switched to a mechanical tilt sensor. An IR LED on the ceiling and a phototransistor on the floor of the box work together to detect the presence of mail.

[Bob]’s homebrew mailbox has a false back that hides a PIC 16F1825. When the door opens, the PIC wakes up, turns on a MOSFET, and checks the battery level. It waits two minutes for the mailman to do his job and then reads the flag state. After comparing the IR LED and phototransistor’s states, it sends a message to the toy mailbox indicating the presence or absence of mail.

The toy mailbox holds a modified receiver board and a servo to control its flag. [Bob] has made the code and schematics available on his site. Walk-through video is after the jump.

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[Bil’s] Quest for a Lost Finger: Episode I

A little over a year ago I had a semi-gruesome accident; I stepped off of a ladder and I caught my wedding ring on a nail head. It literally stripped the finger off the bone. This was in spite of me being a safety-freak and having lived a whole second life doing emergency medicine and working in trauma centers and the like. I do have trauma center mentality which means, among other things, that I know you can’t wind the clock back.

hand9A few seconds make an incredible differences in people’s lives. Knowing that it couldn’t be undone, I stayed relaxed and in the end I have to say I had a good time that day as I worked my way through the system (I ended  up in a Philadelphia trauma center with a nearby hand specialist) as I was usually the funniest guy in the room. Truth be told they ask incredibly straight questions like”are you right handed?”  “Well I am NOW”.

So now I could really use a bit of a body hack, having seen the X-Finger on Hackaday long before I knew that I would one day work with them, I was hoping that we could get one to work for me. In speaking with a couple of the mechanical engineers on the Hackaday staff we decided to get [James Hobson] and [Rich Bremer] involved and that the best way to do it was to get a casting of my injured hand out to them.

 

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DIY Coffee Maker Filters Out Manufacturer Specificity

Coffeemaker made from 3D-printed parts and scrap aluminium

This DIY electric coffeemaker prototype uses an assemblage of 3D-printed parts and cast aluminium. [siemenc]’s main goal with this project was to utilize and demonstrate recycling and re-usability. He used Filabot filament exclusively and melted down scrap aluminium such as cans, foil, and CNC mill waste in an oven he fashioned from an old fire extinguisher. He also cast the aluminium parts himself from 3D-printed positives.

Of course, he had to buy the things that make this a coffeemaker such as the hoses, the fuse, and the heating element. If you’re wondering why he didn’t salvage these parts from yard sale machinery, it’s because he wanted to be able to replace any part of it and have it last as long as he needs it to last. The innards he used are not specific to any model, so he should be able to easily find a replacement.

Just like a pour over set up, [siemenc] has fine control over the strength and quantity of the brew. We particularly like this machine’s exotic bird looks as well; it may be a prototype, but it’s quite stylish. If you’re looking to go all the way with DIY coffee, why not grow your own beans and then roast the beans yourself?