Almost Building An Engine From Hardware Store Parts

engine

You can build a surprising amount of stuff from parts you can pick up at a hardware store. Sometimes, though, getting a project built from sections of pipe is very, very difficult. That’s the case with [Lou]’s hardware store engine: despite an inordinate amount of cleverness, he just can’t seem to get an engine made from pipe fitting to work and is now asking for some ideas from other ingenious makers.

The engine uses regular oxygen and propane tanks you can pick up at Home Depot with torch heads soldered onto half inch pipe. The fuel and oxygen are mixed in a T fitting until a grill igniter sets the gas mixture ablaze pushing a cylinder down the length of a copper pipe. The cylinder is attached to an aluminum flywheel that also controls the opening and closing of the oxygen and propane valves as well as switching the grill igniter on and off.

Right now, [Lou] can get the engine running, but only for one stroke of the cylinder. He’s having a bit of a problem turning this into a working motor. If you’ve got any idea on how to make [Lou]’s engine work, drop a line in the comments. We’ll throw our two cents in and say he needs a valve on the exhaust, but other suggestions are always welcome.

Hackaday Links: December 13th, 2012

Cardboard box computer

links-cardboard-box-computer

[Alistair] chapman had a Laptop with a broken screen sitting in his parts bin. He knew he had an LCD panel on hand that would probably work with it, but it wouldn’t fit in the case. His solution was to transplant all the computer parts into a cardboard box from a motherboard.

This violin is garbage

links-landfill-instruments

The kids in this orchestra live in a villiage built on top of a landfill. But they make the most out of what they have. This orchestra is composed of instruments built from garbage and they seem to work pretty well. [Thanks Bruce]

More LED mystery puzzles

links-led-puzzle

[Henryk] is at it again. He puts together some very impressive circuits that play tricks on your engineering mind. His latest is three LEDs in series. Look closely and you’ll see they’re not performing as expected. Watching the solution to one of his previous puzzles will help you figure out how he’s doing it. His work is simply amazing.

Netbook framed as a dedicated weather station

links-netbook-weather-display

Not wanting to get rid of old but still working hardware, [Retro Toaster] built a dedicated weather station by mounting the screen, keyboard, and track pad in a picture frame.

Current and voltage testing your USB projects

links-USBTesterFront

This dev board is a pass-through for USB devices. It makes voltage and current testing your device quite simple.

How To Used An Android Device With A Shattered Screen

This screen is not just cracked, it’s devastated. We can all agree that you’re not going to be carrying this around with you anymore, but it might still be useful in other endeavors. [Mr Westie] wanted to use it for the camera which is undamaged. The issue is how do you control an Android device with a broken screen?

He knew there are apps out there that let you control your device remotely. But these still depend on you being able to install and launch the program. He found he could get the image from the screen on his computer using a package called Screencast. It runs on your computer and doesn’t need to be installed on the phone, but it will require a rooted phone and the user must click to authorize root access. He got around that hangup by pushing keypress commands to the phone via ADB. The only problem left is if debugging mode is not enable.

Using Two Chargers With One Laptop

dual-charing-jacks-thinkpad

This one’s a riot! [Nico] got a new computer and didn’t want to change the six power supply cords he had strategically placed around his home and at work. So he just added a second charging jack that accepts a different style connector.

First off the laptop is used — but it’s new to him. So cracking it open and soldering in a new jack doesn’t affect the already expired warranty. He had an unlimited supply of Dell laptop chargers available from work. They are rated 19.5V and the charger for this computer is rated 20V so he figured this should be no problem. Instead of just swapping out the old charging port he added a second where the RJ-11 connector (for a telephone modem) was located. Now he doesn’t need to waste money buying more chargers for the new-old machine.

This isn’t the first time we’ve seen someone replace a power jack. But it is the first computer we’ve seen that takes two different chargers.

ARM Powered Rack Mount USB Test Equipment

developing-rack-mount-pcb-testing-tools

This is a device which [Limpkin] has been developing at his day job. It’s a high-speed testing interface for use with Physics experiments. We find it interesting because it uses an ARM microcontroller to implement CDC and MSD over USB.

The design is in two parts to make it work in a rack-mount situation. That big white connector allows cards to be swapped out. You can see the board on the right has a USB-A connector. When plugged in this enumerates as a control device (CDC) and a mass storage device (MSD) using fat32 as a file system.

The platform is being developed with open hardware and open source software in mind. If you’re working on a project that uses either of these USB functionalities this makes a swell reference. The ARM Cortex-M3 chip that he’s using is an AT91SAM3U but it should not be too hard to port the code for other similarly-capable ARM processors.

Python Can Be Your Best Friend When It Comes To Binary Math

python-binary-math

If you’re into microcontrollers you know the ability to think and perform math in binary is a must. [Joe Ptiz] has been looking for a way to keep from being distract by the math when coding while still keeping the binary strings in the forefront of his mind. The solution he came up with is to use the Python interpreter as a binary math aide.

We knew that you could use Python to convert between decimal, hexadecimal, and binary. But we failed to make the leap to using it for troubleshooting bit-wise operations. We can see this being especially useful when working with sixteen-bit I/O ports like those found on STM32 chips. For us it’s easy to do 8-bit math in our head, but doubling that is another story.

The image above is one screenshot from [Joe’s] tutorial. This illustrates a few different bit-wise operators given decimal inputs but displaying binary as output. He also illustrates how you can use python to test out equations from C code by first setting the variables, pasting the equation, then printing the result to see if the output is what was expected.

Rooting Your AT&T U-verse Modem

Unhappy with the performance of his U-verse modem [Jordan] decided to dig in and see if a bit of hacking could improve the situation. Motorola makes this exclusively for AT&T and there are no other modems on the market which can used instead. Luckily he was able to fix almost everything that was causing him grief. This can be done in one of two ways. The first is a hardware hack that gains access to a shell though the UART. The second is a method of rooting the device from its stock web interface.

We think the biggest improvement gained by hacking this router is true bridge mode. The hardware is more than capable of behaving this way but AT&T has disabled the feature with no option for an unmodified device to use it. By enabling it the modem does what a modem is supposed to do: translate between WAN and LAN. This allows routing to be handled by a router (novel idea huh?).