Looks like ice-cube trays are once again proving their versatility as this one is serving as the vessel for a home made lead-acid battery. With a collection of uniformly sized non-conductive containers, it makes the perfect base for a set of small cells. This project is the culmination of a Hackerspace class about batteries, and was put together to turn theoretical knowledge into a hands-on lab.
This is a captured image from the low-quality video found after the break. [Carpespasm] describes the setup; the black pieces are lead plates which are bent into a U-shape to straddle two ice-cube compartments. The each end of the plate is dipping into the acid to make the connection. Once assembled the battery was connected to a charger for about two hours. It puts out 8.5V and is tested by powering an LED cube. This works for just a short period and really drives home the lesson that battery concepts are easy to understand, but reliable battery technology is a bit harder to achieve.
Continue reading “Shocking use of ice cube trays”
[Jordan] likes the flexibility that conductive inks offer when putting together electronic circuits, but says that they are often too expensive to purchase in decent quantities, and that they usually require substrate-damaging temperatures to cure. After reading a UIUC Materials Research Lab article about making conductive ink that anneals at relatively low temperatures, he decided to give it a shot.
[Jordan] started out by picking up various chemicals and lab supplies online, setting up shop at Pumping Station: One. The process is pretty straightforward, and seems like something just about anyone who took high school chemistry can manage. That said, he does note that some of the chemicals, such as Formic Acid, can be quite painful if mishandled.
After just a few minutes of work and about 12 hours waiting time, [Jordan] had himself a decently-sized vial of conductive ink. He tried it out on a few different substrates with varying results, and in the end found that etched glass made the best circuits. He says that there are plenty of experiments to try, so expect even more helpful info from him in the near future.
[via Pumping Station: One]
Back during the Renaissance, great artists like Leonardo, Michelangelo, and Raphael would create their own paints. Of course paint is very cheap and readily available, but that doesn’t mean you can’t make your own paint by playing with chemistry.
Last summer, [Sean] at the Philly hackerspace Hive76 did some experiments with ferrofluids. For these experiments [Sean] prepared a bunch of magnetite from rusty iron screws. In the process a lot of iron hydroxide was formed, which can produce wonderful colors. The red-brown eye in the title pic was made from some of the stuff floating on the top of [Sean]’s beaker.
[Sean] was really after something really black, so he turned his efforts towards hematite, a very dark pigment and is now working with other metals to produce some interesting colors. Already he’s made green and yellow pigments with two copper compounds. We’ll just have to hope he uses a fume hood when he starts taking apart mercury switches to make red.
[Ben] outdid himself. He successfully made monoliths of silica aerogel in his garage. Aerogel, the light-weight solid that has been referred to as ‘hard air’ is really freaking expensive especially in non-granulated form.
The techniques behind producing aerogels have been on the Internet for a fairly long time. A few uncommon chemicals and a supercritical drying chamber are required for production, meaning it takes a lot of know-how to make hard air at home. Somehow, [Ben] got ahold of some tetramethoxysilane, the hard to come by ingredient and made a supercritical drying chamber out of pipe fittings and liquid Carbon Dioxide.
In the end, [Ben] was able to make a few small pieces of aerogel. The size of his pieces were constrained by his “mold” (actually a syringe) and the size of his drying chamber. It’s very possible [Ben] could build a larger supercritical drying chamber and make larger pieces of aerogel that would be sold commercially for hundreds of dollars.
Check out the very informative walkthrough of [Ben]’s process after the break. It’s 10 minutes long and makes for a great lunch break video.
Continue reading “Making aerogel at home”
While many people have tried their hand at anodizing aluminum at home, there are plenty who would just as soon leave it up to the professionals due to the highly concentrated sulfuric acid required for the process. [Ken] started thinking about the process and wondered if there was a way to get comparable results using chemicals that are easier to obtain and dispose of.
Through some experimentation he found that sodium bisulfate (NaHSO4), which is a sodium salt of sulfuric acid, can easily be used in its place with great results. The chemical is typically advertised in hardware and pool stores as “Aqua Chem”, and can be had at a very reasonable price. When paired with the proper DC current along with a cathode, the sodium bisulfate easily anodizes an aluminum workpiece and renders it ready for coloring with RIT, readily available cloth dye.
We were impressed with the results, and when looking at [Ken’s] test pieces, it seems that the metal dyed with sodium bisulfate has a more uniform, less streaky coloring to it. It’s also worth mentioning that [Ken] has found it is fairly easy to etch the aluminum before anodizing using a solution of sodium hydroxide, which is great for individuals who prefer a more matte finish.
If this is something that interests you, be sure to swing by his site. He has a posted nice video overview of the process that may be of some help.
Make: Projects has posted an interesting way to burn designs into wood. Instead of doing the traditional method of using a hot iron to hand draw or trace patterns on the wood, they show us how to use a chemical process to make things easier. They are using a solution of Ammonium Chloride, applied with a foam stamp, then heated. When it is heated it breaks down to ammonia gas and hydrochloric acid, burning the surface. The advantage here is that you can easily use a stamp to create patterns whereas doing it by hand might be difficult. They do point out that improvements could be made, such as adding something to keep it from soaking into the wood and blurring the edges.
Unlike many chemistry projects we post here, making magnetite nanocrystals doesn’t require anything that can’t be found in a local grocery store. All that is required is oil, vinegar, crystal drain opener, and rust. We don’t recognize the specific brand of drain cleaner that they are using, but we’re sure that you could find one with the same ingredients. Magnetite nanocrystals are used to remove arsenic from water. If you are in the USA or most of Europe, that’s not a big concern, but it can’t hurt can it?