Author: Matt Mets

Technically Director of Blinkinlabs, Matt is a maker who uses electronics to create playful objects that teach and inspire. An electrical engineer by training, he's been at various times an RF engineer, embedded systems architect, writer, and exhibit designer. He currently lives in Guangzhou, where he enjoys fast access to the world's largest electronics manufacturing base.

Amazing PC light show made using BlinkyTape

Will from Fuzzletek put together this epic PC casemod, complete with water cooling and a custom light effects using BlinkyTape. Going way beyond a standard chase pattern, he put together a synchronized light show using after effects and a custom software bridge to map the position of the lights into the video. He goes into deeper detail in the making-of video:


From the Blinkinlabs Store:


Howto: Controlling BlinkyTiles using Arduino+FastLED

Jason Coon put together an excellent tutorial on controlling BlinkyTile with Arduino and the FastLED library:

This tutorial will guide you through connecting a BlinkyTile sculpture (I made the standard dodecahedron) to a microcontroller. The same basic instructions will apply to just about any microcontroller, but we’ll be using an Arduino Uno. I’ve also tested with a Teensy 3.1.

He also used this technique to fit a controller, battery, and accelerometer inside a ball. Pretty sweet!


 

From the Blinkinlabs Store:

BlinkyTile kits are now in stock! Get them in the Blinkinlabs Store!

Excellently overengineered bathroom occupancy sensor

Screen Shot 2015-03-13 at 7.14.29 PM

James made this possibly overdesigned system to monitor his office bathroom, using a BlinkyTape, Raspberry Pi, Spark Core, and a paperclip:

The idea is to show the status outside the outer door a few meters away with an “information radiator” to avoid a wasted trip and disturbing occupants by trying the handle. Yes, this could be achieved with some wire linking the switch directly to some LEDs but where’s the fun in that‽ In the spirit of the development team this needs to be massively over-engineered and the greatest amount of micro-processors and micro-controllers should be put between the switch and lamp as is unreasonably possible.

Making the Blinky diffusers: the plastic injection molding process

Injection molded diffuser samples
Injection molded diffuser samples

As an accessory for our BlinkyTile DIY Light Sculpture Kit, we are manufacturing a set of plastic diffusers. We started out by 3d printing them, however it’s not really feasible to produce 100’s of pieces in that manner, and the quality of an injection molded part is way better.

The concept behind injection molding is is pretty simple- you just create two metal shells that, when stuck together, have a cavity in between them which is the same shape as the piece that you want, and then squeeze some hot plastic in there to make the part. Of course, the devil is in the details, and you end up needing tons of pressure (literally) and precision-controlled molten plastic that can be cooled rapidly to spit the part out at the end. The result, though, is that you can produce a large volume of almost identical pieces out of precisely controlled material very quickly and economically. For comparison, it takes about 1 hour to print 4 diffuser pieces on a desktop 3d printer, but less than 30 seconds to produce two pieces using an injection molding machine- that means is over 60x faster to do an injection mold process.

First off, we turned to our friend Nick Starno for a design review of the 3d printed model. Even though we designed it to be straightforward to manufacture (no overhangs or complicated geometries), there were a few things that needed to be tweaked to transition from 3d printing to molding. First, the design had to be made thicker to ensure even flow of the material. Second, the snaps needed to be elongated to reduce the stress on them as they are attached to the BlinkyTile. After making the changes, he performed a Finite Element Analysis (FEA) to validate the design, and it was ready to submit to the factory.

Simulating snap design using Finite Element Analysis (FEA)
Simulating snap design using Finite Element Analysis (FEA)

After receiving the design, the next step for the factory was to cut the mold. They use a traditional CNC machine to make the rough shape, then a neat process called electrical discharge machining (EDM)  to machine the fine details (square corners, etc) that are difficult to machine using spinning tools. EDM uses tiny, high voltages sparks of electricity to wear through a piece of hardened metal, rather than cutting it with a spinning blade like a drill or end mill. The EDM process looks like this:

EDM tool sparking away metal
EDM tool sparking away metal

And the resulting metal mold looks like this:

Metal mold ready for injection
Metal mold ready for injection

The green stuff on the mold is a grease that protects the metal from oxidation while it is in storage.

After finishing the mold, the factory loaded it up into the machine and produced samples (first shots) of the design for inspection. The purpose of this was both to evaluate the physical shape and condition of the parts (do they fit in the PCB tiles? are there any ugly surface features?), as well as test that the material produces the right amount of diffusion.

Once the samples were ready, we went to visit the factory and inspect them in person. Over some delicious tea, we inspected the samples and found the design to be spot on.

First shots of the BlinkyTile diffuser
First shots of the BlinkyTile diffuser

We had 5 different material types to choose from, from transparent to full white opaque. After some careful evaluation using our Disco Party app, we settled on the ‘B’ variety:

Looks good!
Looks good!

A few days later, and we’ll have more pieces then we can count! Don’t worry, we can determine the amount by weighing them.

Announcing the BlinkyTile!

Hi everyone, Today is an excellent day for three reasons: Blinkinlabs is exactly one year old, it’s the start of World Maker Faire and we’ve got a great exhibit for you, and… we’re launching a new product! If you’ve been watching closely here, you’ve probably seen glimpses of a new blinking light structure. It’s called the BlinkyTile and it’s a system for making your own dynamic light sculptures using pentagonal tiles. It’s on Kickstarter now, act fast and get an early backer reward! Screen Shot 2014-09-20 at 8.05.32 AM blinkyball

Prototyping tutorial: Quick and dirty solder paste stencils

PCBs made with a DIY stencil

Solder stencils are pretty cheap these days, but for a single, quick production run of a really simple design, it seems like a waste of resources to have a professional one produced and shipped to the lab. Of course, if you have a laser cutter handy, you can make a pretty nice one, but if all you’ve got is a rusty knife and some office supplies– don’t fret! You are still in luck.

I’m actually pretty stubborn, and until recently I would just solder this kind of job by hand. This time, though, my good friend Honghong was around to set me straight- she explained a totally cheap and dirty procedure that they use at her factory to make stencils quickly. We tried it out here, and are happy to report that it works great!

It It turns out that soldering stencils aren’t really anything special, at least for large components- they’re basically just pieces of thin material with holes cut in them. In fact, you probably have all the material you need to make one right now- a piece of transparency sheet or velum, a knife, and some tape. So without further ado, the instructions!

Step 0: Gather materials

You will need:

  • 1 sheet of velum, preferably 2-3x the size of your PCB
  • 1 sacrificial PCB for the template
  • Masking tape
  • Xacto knife (the sharper the better)

Step 1: Tape the velum to the PCB

Tape velum to the PCB

Use masking tape to secure the PCB to the velum. The top side of the PCB should point towards the velum.

Step 2: Cut holes in the velum

Cut the mask

Use the X-acto knife to cut out openings over the SMT pads on the circuit board. I cut out little rectangles. If you have a small drill handy, you could also just drill holes here.

Step 3: Check the hole alignment

Inspect the PCB mask

Once you have the holes all cut out, double check that the holes line up with the SMT pads, and that there aren’t any rips or tears in the paper. I messed up the first one, but after replacing the blade on the knife, the second one was fine.

Note that I intentionally left out the big component in center of the board- that one is an LED that would be damaged by this reflow process. Those will be soldered on by hand later.

Step 4: Make a simple jig to hold the PCB in place

Make a temporary jig

This is optional, but will help speed up the assembly process. Tape some old PCBs to a thick sheet of paper, forming a corner for your board to fit into.

Step 5: Align the solder stencil, and apply the paste!

Apply solder paste

Place the solder stencil over the board, and align it to the correct position on the board. Next, apply solder paste using a squeegee tool. Carefully peel back the stencil and remove the PCB.

Step 6: Inspect

Inspect the finished PCB

If all went well, you should now have a PCB with solder paste on it! Add components using your favorite method (tweezers, vaccuum pen), and reflow the board.

Conclusion

This is a truly quick and dirty method for making solder masks, and is nice because it only requires a few hand tools. It’s great for situations when you want to test a new design or make a single, small run of boards, but don’t want to waste time and money on a professional stencil. Share how your build works in the comments!