Fail of the Week: Transparent Circuit Design is Clearly a Challenge

[Frank Zhao] wanted to try his hand at making a transparent circuit board. His plan was to etch the paths with a laser cutter and fill in the troughs with conductive ink. The grooves are ~0.1mm deep x ~0.8mm wide.

He used nickel ink, which is slightly cheaper than silver ink. The ink was among the least of his problems, though. At a measured resistance of several hundred ohms per inch, it was already a deal breaker since his circuit can’t function with a voltage drop above 0.3V. To make matters worse, the valleys are rough due to the motion of the laser cutter and don’t play well with the push-to-dispense nature of the pen’s tip. This caused some overflow that he couldn’t deal with elegantly since the ink also happens to melt acrylic.

[Frank] is going to have another go at it with copper foil and wider tracks. Do you think he would have fared better with silver ink and a different delivery method, like a transfer pipette? How about deeper grooves?


2013-09-05-Hackaday-Fail-tips-tileFail of the Week is a Hackaday column which runs every Thursday. Help keep the fun rolling by writing about your past failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.

DIY Conductive Paint For All Your Wearable Needs

DIY Conductive Paint

Conductive ink or paint is lots of fun. It opens up tons of possibilities for flexible and unique circuits — unfortunately, it’s pretty expensive. [Brian McEvoy] shows us how to make your own for cheap, and it works great!

He started trying to formulate his own recipe after playing with other Instructable guides and commercially available paint, and what he found is it’s really not that complex! Graphite powder, acrylic paint, and a jar with an airtight seal — seriously, it’s that simple! But, like any engineer worth their salt (he calls himself the 24 Hour Engineer), he had to do some tests to compare his formula.

In a detailed experiment he compares his formula to the commercially available Wire Glue, and two other recipes using Elmer’s Glue-All and graphite, and Titebond III with graphite. The results? Acrylic paint and graphite produce the most conductive material — and the cheapest!

Now that you can make conductive ink, why not 3D print a circuit stamp to make your very own SMD circuit board!

CartoLucci: A Candle-Powered Christmas Card

cartoLucci

If you’re looking for a last-minute Christmas present, you probably won’t have enough time to reproduce [Helmar’s] candle-powered Christmas card. He’s been working on it for a few years now, since his first prototype in 2010. Though he pieced together the original card with parts lying around his workshop, the most recent iteration looks like it belongs on the shelf in a store.

We last saw [Helmar’s] work two years ago, when he shared his Full Color Laser TV. This project is a bit more compact: the circuitry was printed with conductive ink on the cardstock, and all the required components are held together by conductive adhesive. To power the electronics, he decided against a battery and instead chose to embed a solar cell on the inside of the card. Placing a lit candle inside the open card provides enough juice for the exterior of the card to shine.

You can see a video of both the current and prototype versions of [Helmar’s] cards after the break.

Continue reading “CartoLucci: A Candle-Powered Christmas Card”

3D printed circuit boards using conductive ink

The thought of using a 3D printer to fabricate PCBs is tantalizing and the good news is that it’s a reality. This project shows that it’s possible to use a special printer head to apply traces to an extruded substrate.

This is similar to the point-to-point 3D printer circuits with one big upgrade. Now the traces can be printed directly onto the ABS using conductive ink. The process starts with the design files, which are used to model a substrate that has a trench for each trace. A Makerbot then prints out this model. Once complete, the ABS extruder head is swapped for a special ink head. Each trace is then filled with the conductive fluid, which is kept in place by the trench walls until it can dry. We think this improves on the trace printing techniques we’ve seen before because it doesn’t require your printer heat to use molten metals.

The circuit above uses printed traces for the high and low side of an LED circuit. It’s a bit rough at the edges, but it shows a lot of promise. Don’t miss the demo video embedded after the jump.

Continue reading “3D printed circuit boards using conductive ink”

Conductive ink circuit experiments

This glowing LED is proof that the experiments [Nvermeer] is doing with conductive ink are working. We’re filing this one as a chemistry hack because  you need to hit the lab ahead of time in order to get the conductivity necessary for success. He reports that this technique uses a copper powder suspended in an epoxy intended for spray painting. Before mixing the two he etched the powder in ammonium persulfate, then washed it in deionized water which made it a much better conductor.

We gather that the ink was applied with the brush seen in the photo. But since this uses that spray paint friendly solution to host the copper powder we wonder about stenciling with something like masking tape in order to spray the circuit paths onto the substrate.

There’s not too much info up yet, but [Nvermeer] does link to one of our other favorite conductive ink projects.

DIY Conductive ink lets you freehand circuits on the cheap

silver-ink-on-glass

[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]