Evolution of a Gear-Clock

News Flash: I love to make things.

The explosion of home use fabrication technologies has given modern humans powers, god-like powers that we could only dream of even 10 years ago.  Digital design and fabrication are now accessible to practically everyone.   Those that do not have fabrication facilities at home can use services like Shapeways, 3D hubs, Oshpark, and Ponoko. to fill the gap and create practically whatever they can dream up.  What are you doing with your god-like powers?

I’ve been asking myself this same question lately and it turns out that I use them to make clocks.  Funny thing is I’m not really a clock person, but I know that I need to learn how to use these tools: 3D printing, laser cutting, circuits, and clocks seem to be the go-to target for my aspirations.

This led to ClockTHREE and ClockTHREEjr word clocks and also a Kandy, a two-sided race timer.  But none of these clocks have moving parts.  I figure I need to understand mechanical issues to really employ my god-like powers when inspiration hits.

Motivated by clocks like this one from Brian Wagner I set out to design my own version of the gear clock.  GearClock1.

Screenshot from 2015-03-01 10:33:49

Like Brian’s clock, the hour wheel rotates indicating the hour at the top.  Unlike Brian’s clock, and others, this clock uses a idler gear to push hour ring out to the radius of the minute hand.  The parts are a made with laser-cut acrylic and 3D printed PLA.  A single hand is attached to the drive axle to indicate the minute on a stationary disk, concentric with the hour ring.  AlaMode, which comes with a DS3231 real time clock, was used in conjunction with the Adafruit motor shield to control movement.  Blue accents really make this clock pop.  But the clock had mechanical issues and would bind up frequently.

I realized that if I replaced the idler gear with a planetary gear, It could drag an hour hand along for the ride like a normal clock.  GearClock2.



After first getting the gear ratio wrong (how many hours in the day are there again?) I got it right.  Kevin Osborn jazzed up the design with some sick filigree hands and taught me how to draw in InkScape and import into OpenSCAD.  He also printed all of the many iterations of gears on this and previous clocks.  Thanks Kevin!

The clock looks pretty basic, and it is, but remember my goal is to learn mechanics and I learned a lot with this clock.  Form follows function.  I take that to mean, first make it work, then worry about how it looks.  It can also mean: make it work really well, and its shape will appeal.  We are getting there.  The good news is this clock really works.  We have it set up on a hutch in our kitchen and use it every day.  But I have to admit, the shape is a little awkward and the electronics are unsightly.  The cheap 48-step motors tick every 75 seconds, which is more than frequent enough for a wall clock, but we can do better.

GearClock3 is the same basic mechanical design with a 200 step pancake motor and electronics housed in a separate box.


An Arduino pro-mini, a Pololu stepper driver, and a Chonodot make up the electronics package.  I really like this stepper driver.  It is very easy to use: set the step pin to HIGH to move forward one step.  No complex driver software is required.

Aesthetically, this clock has many of the right elements although a flash of colored acrylic would really make the numbers pop.  Everyone loves GearClock3, but the first thing they ask is: can you do seconds?

GearClock4 adds a second hand.GearClock4

I’ve come to appreciate the difficulty of the standard hour, minute second clocks: Three concentric hands driven at three rates with a ratio of 3600:1 between the hour and second hands.  A 12:1 ratio was already working with the planetary gear.  The 60:1 ratio was solved by using two reduction stages that take the motion off center, then back on.  After several experiments with the gear lash settings, I finally found a combination that works well and makes a pleasant tick (not too loud).  One issue is setting this clock.  You have to fast forward the second hand, which means you’d like to move the seconds hand as fast as possible.  This second hand can turn a complete revolution in 0.2 seconds which means it can fast forward though twelve hours in less than two and a half minutes.  A sealed bearing on the reduction gear allows this and should work for years to come.

What’s next?  Anool is working on a custom circular PCB that will that will bring the electrics up to par with the mechanics.   The PCB will host the real time clock, an Arduino compatible ATMEGA328, hall effect sensors to detect hand position, and a DS3231 real time clock, and GPS unit for time synchronization.  Stay tuned to our GitHub repo for updates….


Låda, a custom project box system


HALO is an EL-Wire night light. Photo by Emily Shaw

Project boxes can be a real pain. You can get a standard size box from a place like Radio Shack or you can make your own custom box. If you have access to a laser cutter, you can make yourself t-slotted boxes.  While the t-slotted boxes do the trick, the open slots leave an unfinished look to projects.

I wanted a more polished look for my latest clock, so I set out designing Låda.  The Låda (or Lada) Sytem, based on standardized 3D printed corner and edge pieces and custom laser cut face pieces, allows you to define a box of any size bigger than about an inch and a half on a side.  A program written in Python does all of the tedious calculations for you and spits out a PDF file.  Custom openings can be added with InkScape to accommodate stand-offs, buttons, cords an sensors.lada_diagram

The edge and corner pieces have mounting holes 0.4″ from the inside face.  They have an elevated platform to cradle your project.  Hex cutouts captivate a M3 nut so that once installed, they remain in place and the box allowing the final face to be screwed into place.  +Kevin Osborn has been keeping our 3D printing non-stop so that now I have plenty of Lada pieces to play with.


HALO consists of an AlaMode, a Grove Shield, and an EL-inverter. Photo by Emily Shaw

The Lada system works fine for small projects like the EL-Wire night light seen above.  It also works with larger projects, like the Kandinsky Klock (or Kandy) for short.


DSC_0539 DSC_0540

About the projects:

Halo is an EL-Wire night light configured to outline a doorway.  It helps to prevent falls by both providing light, and creating a frame of reference to orient you if you need to be up in the middle of the night.  I made it for my father who could use a little assistance getting to the bathroom in the middle of the night.  The idea comes from a story I heard on NPR.

Halo was easily assembled from: an AlaMode,the Grove Starter Kit, and a USB based EL-Wire inverter.

A special thanks to +Kevin Osborn who lined me out on what I needed to drive EL-Wire and pointed that the Grove Started Kit had everything I needed aside from the inverter.

Kandy is a two-sided mountain bike race timer that I’d promised to build for my collage roommate two years ago.  It is 4 TiM boards with c prototype LED controller called TiNA.  It is bluetooth controlled (thanks to the FTDI compatible BlueFruit module).  I think it is worth the wait.

None of these projects would be possible without Anool’s tireless work designing amazingly flexible circuit boards.

WyoLum goes to MakerFest 2014 at Ahmedabad, India

The first week of January had me and Samata Mahidharia driving down to Ahmedabad, about 550 kms North of Mumbai. We were on our way to attend MakerFest 2014, organized by the awesome folks at Motwani Jadeja Family Foundation, at the uber-cool design school – National Institute of Design.

WyoLum gave away 40 of our BADGEr – e-paper conference badges for Makers attending the Maker Fest. We didn’t have time to program all the BADGEr’s , but the Makers were kicked to be able to take them away and get hacking. I took a few pictures.

I gave a talk about the Maker Movement – talking about how the Maker revolution is bringing us back to our Maker roots, using my personal experiences as examples.

Samata and me did an Origami Workshop. The initial plan was to limit attendance to 20 people in a classroom. Eventually, a much larger number of people turned up, and the organizers asked it we could accommodate all. Seeing as how enthusiastic everyone was, we just couldn’t refuse, and moved our workshop to the main stage of the open grounds. It was wonderful to be surrounded by almost 50-60 folks – from little kids to grown ups, eager to learn some folding. Due to the large crowd, and also that no one had a good flat folding surface in front of them, we cut down the original plan of folding about 6-7 models in an hour to a more manageable 3 simple models. Eventually, I think everyone managed to fold the models – a tumbling toy, a cawing Crow and a Swan.

The most exciting event for Samata and Me was to team up with Albie Brown and run a MakerFest Treasure Hunt. Up for grabs was a bag full of goodies, including a WyoLum BADGEr, a BeagleBoneBlack and other cool stuff.

Visitors to the Fest were handed over a “Guide for Hunters

This explained how the hunt worked. On the back of the sheet was a list of 100 words, numbered 00 – 99. Only five of these were relevant to the final solution of the puzzle, the remaining 95 being duds. Hunters were asked to stroll through the booths at Makerfest 2014, where they had to find, and solve, five mini puzzles.

The starting “hint” was that there were a few logos on the clue sheet that indicated which booths are presenting challenges. In no particular order the five booths were:

  • Education for Design (e4d)
  • Microsoft Research
  • WyoLum
  • FabLab
  • Printajoy
  • E4D is working towards bringing education to everyone. Beginning with a handful of Centres in southern India, they are building a higher educational model focused on reaching the masses, rather than building universities. They seek to minimize infrastructure and costs, while taking full advantage of freely available online educational resources. Their activities also include education for blind persons. Their clue was – What is the name of this code spelled backwards? This hint was written in braille on a piece of a can and the can was glued to a stick of bamboo. Puzzlers had to translate the braille and answer the question to solve the clue. The answer was “elliarb

    Microsoft Research is working on conductive ink printers made from regular Ink Jet Printers, but using special cartridges filled with ink made from Silver nano-particles. These printers, along with a range of sticker adhesive elements, allows designers to quickly fabricate prototypes. Their clue was – “What am I made of? (Hint: they sometimes call me 47)” and the answer was “Ag” (the symbol for silver).

    WyoLum put up one of their ClockTHREEjr with a code written next to the clock – C1F8D1H1N9G6. Reading off rows and columns (C1, F8 etc) gave them the word “Patang” which translates in to English as “Kite

    The MJFF donated a $140,000 Fablab from MIT to the maker community in Ahmedabad. The Fablab is a set of digital fabrication equipment and software to help makers transform their imagination into products. The Fablab is housed at the prestigious CEPT University Ahmedabad and will be open to the public at select hours every day. At the Fab Lab booth the manager told puzzlers to press print. They had to figure out how to use the vinyl cutter and print a document that was concealed by coloring all components black so the text was invisible. The machine then cut out the word “Replicate” in sticker form and the puzzlers had to pull off the sticker to reveal the answer.

    Printajoy is a photo printing service for Instagram photos – a “Print button for your Instagrams” India’s first affordable, online printing solution that converts your Instagram photos into beautiful lifetime memories! Their clue was – “There is something hidden underneath every Smile”. Then under the deck of business cards (which said smile on the front) there was one card with a label with the word “Memories” stuck to it.

    If you solved all five puzzles you ended up with five answers and five two digit numbers. Several teams kept asking us to check if they’d got all the right words, but we just encouraged them to continue going.

    At 3:30 we revealed the final clue. Albie wrote out the clue on a white board, and held it up for everyone to see

    _ _ _ _ _FEST

    The first alphabet taken from each our five answers, when placed in the right order formed the word MAKER. Almost everyone filled in the blank with “MAKER” but were flummoxed when we encouraged them to keep going since the hunt was not yet done. The smart winning team realized very quickly that the numbers still have not been used. “MAKER” indicated the order in which to use the 10 digits, which gave a phone number. When they called the number, they won!!! The winning team called the phone number within a minute of our releasing the final clue. Not just that, they even followed Albie who ran behind the stage when he picked up the phone they had dialed, and told Albie – “Turn around and look here – I’m the guy calling you”

    In the middle of the Maker Fest grounds, we set up a pop-up Maker Space where the makers got together and started building and showing off stuff to visitors, and encouraging them to join in. There was a lot of Arduino, flexible sticker circuits, wearable electronics, PVC pipe Lamp shades and other stuff going on. Samata even stitched a quick Dress from an old Saree and sewed a string of LED’s around the neck. Apparently she did a Ramp Walk with the LED dress in the auditorium, but I wasn’t around to witness the awesomeness !

    I set up a PolarGraph drawing robot. I had received the kit a few days before heading off for MakerFest, and had no time to get it working. At the Makerspace, I tried setting it up, and even managed to get one trial print. But I was constantly being interrupted by eager visitors asking me what it was, and ended up spending all my time telling them what it was supposed to do. I even managed to show it off to Mr. Sam Pitroda

    At the end of the second day, the MakerFest was wrapped up with a Panel Discussion featuring a bunch of Makers – Angad Daryani – a young Maker from Mumbai , Spandana Cheruvu – another young maker , Anand Gandhi – Ship of Theseus film maker , Freeman Murray from Jaaga Bangalore, Anna Waldman-Brown curator of MakerFest 2014 , Myself, Vaibhav Chabbra – from the EyeNetra team and also running Makers Asylum in Mumbai, Ankit Daftary – from the Arduino India team, Bangalore , and Kshitij Marwah from MIT Media Labs

    Thanks to everyone who participated! We had a great time putting it all together! We met some amazing Makers from all of India. Some of them we knew via Facebook or Twitter or Google, but meeting them in person was wonderful. And we made a lot of new friends ! All in all, this years MakerFest was a blast and we look forward to next year’s MakerFest.

    Reserve BADGEr_v4 available in our shop

    Rather than pay the huge shipping costs to send the remaining 19 BADGErs back to Seeed Studio, Amy volunteered to ship them from our house.  You can pick them up in our reserve shop.  Thanks!