Category Archives: How-To

Spark Core meets CrashSpace, gets stern upbraiding

We had a really good turnout and raised $190. Matt led the charge, Metal kept things lively (and taught me how to deal with a broken strand in a Bukito), and I took it way too seriously for a while. Nevertheless we learned a lot about the Spark Core device and how to get them working.

Spark Core meets CrashSpace, gets stern upbraiding

By the way, I can’t thank Barb enough for designing the two kinds of covers for the Cores with Internet Button shields: flat topped, and domed. Pimptastic!

Each of us found different ways to break the Cores, rarely trying to do so:

  1. Chris found that certain library functions are not quite supported by the firmware. He could nearly brick a Spark Core and it took a while to recover. Chris, would you mind sending me the commands that did this (or at least a link to the code, since it was one of the examples)?
  2. There are at least a couple sketches on the Spark web site that do not compile in the web IDE, let alone run on a Spark Core — the code is out of date.
  3. Of the 12 Spark Cores we received, 3 needed special attention before they could download and run a sketch. This hints at a serious quality control problem. This definitely does not bode well for what is supposed to be a plug-and-play tool, Arduino killer, or MCU board with as much space and power built into it (ARM Cortex M3 72 MHz, 128 kB flash, 20 kB RAM; an extra 2 MB storage off-die; and a TI CC3300 WiFi chip).
  4. The default instructions for getting a Spark Core running often fail. They cannot be used at all in an environment with more than one person trying to sync a new Core: the phone app will just grab any broadcasting Core it finds.
  5. We worked through several syncs, so we now have a clearer set of steps for getting someone up and running without the vekakte phone app. I need to finish typing them, as there are different steps for Windows, Mac, and Linux.
  6. Having to flash a sketch by typing it into a web site and sending it via WiFi is inefficient. The device’s WiFi features are more interesting during runtime, and we just scratched that surface. Flashing the sketch via USB.

On the positive side:

    • We had a visitor that got his Core to text him every time he did something (see the pic at the top of this post);
    • Daniel got a working Big Button like there wasn’t anything to it (because he rocks);
    • Many eyes, hands, and minds made it easy to detect and workaround problems. That was a lot of fun!

Spark Core meets CrashSpace, gets stern upbraiding

    • We could use the existing Neopixel library with the Internet Button shields and get that happy RGB glow.

Spark Core meets CrashSpace, gets stern upbraiding

I will submit docs to Instructables once I have everything in steps-and-pics order.

Instructables / Dremel July Build Night

On July 6th, Crashspace hosted a Dremel July Build Night.  Much fun was had by all while experimenting with Dremel 4000 rotary tools and oscillating Multi-Maxes.  There were carvings on recycled wood and a rock; there was metal cutting (and fun sparks!); one person used a sanding attachment to smooth irregularities on a piece originally made on a CNC router.

 

See more photos from the Dremel July Build Night.

In response to the event, Barb created two featured instructables using the tools we were sent – Wooden Rag Doll and Upcycled Sofa Foot Box:

Instructables / Dremel July Build Night
Instructables / Dremel July Build Night

MakerBar Hosting MAKER CAMP 2014

ABOUT MAKER CAMP: Maker Camp is a 6-week virtual summer camp for anyone interested in DIY, making, creating, crafting, hacking, tinkering, and discovery. Maker Camp 2014 starts July 7. MAKE and Google+ host an online Maker Camp in the summer.  This year the camp begins July 7th, with a different theme each week.  New projects to work on are posted each week.  It’s geared towards teens, but anyone can participate. MakerBar is pleased to be hosting this camp, and look forward to a future full of Maker Camps…. Join us!!

We will be meeting once a week to work on projects… More Details to follow soon!

Here’s a link for more info on MAKER CAMP 2014
http://makercamp.com/summer-2014/

Here’s a link to our meetup to reserve your spot(Volunteers Welcomed):
http://www.meetup.com/MakerBar/events/192022032/

MakerBar to host new Software Defined Radio Night Friday, June 13, 2014

BEGIN TRANSMISSION:

‘We interrupt this broadcast transmission to bring you special breaking news report… live from Hoboken, MakerBar….’

Join us as we explorer the air waves with Software Defined Radio(SDR)… Doors Open at 7PM..  Also we will be running our OPEN CRAFT NIGHT as well. Bring a project, in any shape or form, hack the night away with us….

Or just come by explore the space, have a beer with us and see what creations are developing in the MakerBar community…..

MakerBar to host new Software Defined Radio Night Friday, June 13, 2014MakerBar to host new Software Defined Radio Night Friday, June 13, 2014MakerBar to host new Software Defined Radio Night Friday, June 13, 2014MakerBar to host new Software Defined Radio Night Friday, June 13, 2014

END TRANSMISSION.

For Meetup info:    http://tinyurl.com/MakerBar-Radio-SDR-Night

MakerBar to Host Instructables Dremel Build Night!


Instructables and Dremel have selected MakerBar as one of its locations to host a build night to learn Dremel and create awesome things!

We will be Dremel-ing and writing up our projects for others to learn via doing through the power of sharing knowledge. After a 15 minute safety demonstration, we will have five Dremel rotary tools with accessory kits and three Dremel reciprocating tools to make a mountain of awesome projects! We have a lot of things at MakerBar that could serve as the foundation for projects, but we want your ideas, your participation, and your projects to shine here. Bring any materials you may have and transform them into science, art, or something unique.

All are welcome, and the event will begin at 7:30 with our safety demonstration.

Come out and build things with Dremel tools and learn how to make your projects a reality fast!

See you there!

Sign up on the meetup!
http://meetu.ps/2p5N1T

MakerBar to Host Instructables Dremel Build Night!

MakerBar to Host Instructables Dremel Build Night!

Wood Burning Class Next Saturday: Still Time to Sign Up!

MakerBarBarians and Friends, back by popular demand is another edition of the intro to Wood Burning and Image Transfer class. There’s still time to sign up to learn this rewarding hobby and take home your own burning iron to customize your own wood projects.

Sign up here at Meetup: http://meetu.ps/2lY7ZM

Hello Processing

If you want to learn to code, Processing is a great place to start.  You can download the Processing editor for free, or you can do a quick intro tutorial without downloading anything right in your web browser.

Hello Processing

It’s part of the Hour Of Code project, and in addition to the tutorial video with Daniel Shiffman, it has a fully functional Processing editor right there.  You can change the examples, or you can make your own programs.

Get started right here!

Found @ CRASH Space No 6. – USB LED Light goes Dieselpunk

Finished Light

The finished light plugged into a USB hub

So there was a delay this week in the F@CS series. Why? Because I met my match in a part that is taking more research than I originally intended. It has the location of a factory printed on it so I’m doing a bit more humanities-style research on it.  Please stay tuned.

The change-of-course-project is a mod of an  USB LED light.  I stumbled onto an inspiring Instructable by Winged Fist called Dieselpunk USB Lamp that has links to other Dieselpunk and Steampunk style mods for modern technology.   My version uses more lamp-parts and 10mm LED, but the spirit is the same.

More pictures are up in a flickr set, including the original USB LED find from our donations pile.

If you decide to make your own, please note two important  missing pieces from the Instructable: any mention of a current limiting resistor or a link to how to solder wires together. It is tiny, but you can see a resistor soldered to the lead wire of the LED in the Instructable. I would have liked him to call that out as important. I know the original current limiting resistor in my hacked object came out in the dismantle.

To make a lot of these without designing a PCB or soldering wires together, go to Mouser and order something like the Visual Communications Company’s CNX LED Socket with the integrated resistor option. They’ll be more stable than a wire to wire connection and the LED can be swapped in the future. Some items in the line have lens accessories.  Also, they are less than a dollar if you are getting the part without lead wires.

Tools Used

  • Wire Snips (Drawers on top of benches on the west wall of the large lab)
  • Wire Strippers (Drawers on top of benches on the west wall of the large lab)
  • Glue gun (Shelves above the benches on the west wall of the large lab)
  • Small screwdriver (for dismantling the original) (Drawers on top of benches on the west wall of the large lab)
  • Scissors (for trimming hot glue) (Drawers on top of benches on the west wall of the large lab)
  • Soldering Iron (Shelves above the benches on the west wall of the large lab)
  • Silver Sharpie (For the phono connector. My stash – but there may be one in the drawers on top of benches on the west wall of the large lab.)

Supplies Used

  • Solder
  • Hot Glue
  • 470 Ohm Resistor (The dismantled light was using a 56 Ohm resistor. This makes sense given Ohm’s Law:  5 V / 100mA USB current limit = 50 Ohm. I wanted a lower voltage and less current on my chosen LED to maximize longevity and create a moodier light. The new circuit only draws around 10 mA.  We have LOTS of resistors in the drawers on the east side of the large lab and on the shelves below in the “Misc Components” box. Thanks Steve G.!).
  • 10mm White LED (10mm looked more bulb-like, found in the drawers on the east side of the large lab. Thanks Matt P. ?)
  • The outside plastic sleeve from a Phono/RCA connector (Radio Shack)
  • Lamp Parts (my stash, originally from Lampstuff.com)
    • #09257 2 inch pipe, Nickel over Brass
    • #08610 Solid Brass Knurled Nut
    • #08631 Heavy Duty Brass Plated Nut
    • #08453 Nickel Plated 1/8 IPS Lamp Socket Cap (i.e. the bottom part)

 

 

Found @ CRASH Space No 5. – Tactile Swiches

Finished Viewer From op
United States Patent US3133170 (1964)
P1000133

Tactile momentary switches are magic.

Think of all the giant heavy toggle switches and spring-based momentary push buttons on some of the older electronics you’ve seen and we still have. Crazy satisfying to play with but heavy, clunky and big.

Now picture tactile switches, or tact switches, that still manage to have a physical snap and yet are tiny.  Their physicality comes from the deformation of a metal dome that may or may not also serve as one of the electrical contacts. The clicky seal-intact indicator on jar lids is that kind of spring.

These switches represent a huge step in miniaturization and production automation.  The technical drawing (shown middle left) was captured from the oldest patent I could find using this technology. Everything else I saw from before this before was using coil springs. Current patents filed are all about improving reliability, manufacturing and size.  There are some others in  F@CS No. 5 Flickr set and I’ll be posting more.

The reason I’m writing about them for this series is because someone kindly donated a handful of 12mm tact switches to our parts bins. I enjoy poking around to see what new stash has shown up in the unlabeled drawers.  So this is a little how to on how to use them in finished projects (not just exposed on breadboards or raw pcbs) and a bit of a buying guide if you want to source your own.

Using Tact Switches

A good example of tact switches in the wild can be found here on this very website in Take Apart Tuesday No. 8: Saw III Digital Voice Recorder. The fewer buttons a device needs, the more likely designing a membrane switch pad wasn’t worth it.  Also they can be pretty sturdy in terms of press counts and come available in dust and moisture resistant sealed packages.  I’ve found them as  the eject buttons on external optical drive, under printer buttons, in radios, in digital cameras…  Once you start taking things apart it becomes hard not to try and imagine what kind of button mechanism is under the case.

I suspect the ones I found are the E-Switch 1100 Series, but I couldn’t quite identify the cap accessory.  It is very useful to have the snap-top / plunger for cap type like these are when you are going to make your own buttons. The round caps can be slippery. The human pressable operating part must line up with the circuit below.  Anything other than perfectly centered right angles can cause electrical noise and decreased life span of the switch.

I only found one cap on Thingiverse, and it is a good example of how to make your own illuminated tact switch caps.  If you want to make a 3D printed part, manufactures sometimes supply cad files. Omron has theirs up on their own site’s CAD library and via Trace Parts Online

My example project for this was to make a little slide viewer out of laser cut wood and sanded acrylic. The button is bass wood from a hobby shop. The box was started by an online box generating tool and then modified.

 Finished Viewer From op  Slide Viewer Inside From SIde  The tactswitch with operating hardware
 The notched wood  SlideViewer1

It works well, is stable and didn’t take long.   No soldering even.

Tools Used

  • Laser Cutter
  • Small screw driver as a chisel (don’t tell)
  • Wire strippers
  • Hack saw

Supplies Used

  • Sand paper
  • 1/8 inch plywood
  • 1/8 inch acrylic (sanded)
  • 10 mm LED (white)
  • 1 Ohm resistor (or 24 feet of 26 AWG wire, your pick)
  • 2 AA Battery holder
  • 2 rechargeable AA batteries
  • Small breadboard
  • Bass wood dowel
  • 26 AWG wire

Buying Your Own

The TL;DR

  • The easiest thing to do is to go to either SparkFun or Adafruit and buy what they stock.
  • If you want a switch like in the inventors kits: 12 mm, Through Hole,  NO, SPST, top actuated, standard or round actuator style, 160gf, 0.05A @ 12V or 24V, expect to pay between $0.50 and $1.00 if you are only buying 1 or 2. AdaFruit sites theirs as being the Omron BF3 series
  • The one I used in the slide viewer: Mostly the same but with an actuator style called “snap-top” or “plunger for cap”
  • One like used to be on the Arduino: 6mm, Through Hole, NO, SPST, top actuated, standard or round actuator style, 160gf, 0.05A @ 24V, expect to pay $0.37 or less for small quantities (Listed as Digikey SW400-ND)
  • The one that is on the Arduno Uno / Leonardo boards is like before but the mounting type is surface mount (gull wing style) with a grounding pin.

First, if you haven’t bought a lot of switches and abbreviations like SPDT (single pole double throw) and NO (normally open = broken = off) mean nothing to you, go watch the Digikey product training manual called Switch Basics provided by them and NKK. The Digikey PTM‘s swing between really informative and marketing schlock.  This one explains circuits and package types, etc. with minimal “NKK is so awesome love us” side comments.

Going from the Mouser and Digikey websites, these are some of the things to consider:

Manufacturer: Is there someone who’s stuff you like or that your company has a relationship with? Some of the big ones include C&K, NKK, ESwitch, Omron, and ALPS which hilariously has trademarked the phrase (caps included) TACT Switch™  Looking at manufacturer sites can be educational/ Putting their names into Google Patents or Free Patents Online with key words about the product you are planning to source from them can also be kind of entertaining. I put some of those pictures in the F@CS No. 5 Flickr set as well.

Operating Force: How hard do you have to press the plunger to make it move. Choice of 160± 50 gf or 260± 50 gf is what the data sheet says for our switch.  gf stands for gram force, or the effect of “standard earth gravity” on a gram of material. You can internalize this as how many pennies would you need to stack on the switch to get the plunger to move.  If you prefer Newtons here is a conversion chart.

Actuator Type:  Really describing the packaging for the metal dome or lack there of.  There seems to be a lack of consistency in words to describe them. Mouser refers to the one we have as “Snap Top” in Digikey it falls under “Plunger for Cap.” The bare metal dome can be purchased if you want to try building your own mechanism. There are square buttons and round buttons… you get to pick.

Current Rating, Voltage Rating AC/DC, Power Rating: All of these are descriptions of how much of an electrical load will the switch be required to carry. Generally tact switches are used with a micro-controller, so the power loads shouldn’t be too big of a deal.   If you are looking for a push button for a higher current application that is exactly what you should be looking for a pushbutton switch.

Contact Form (Mouser) / Circuit (Digikey): This is where knowing what NO SPDT means comes in handy. Go watch the module. It has graphics.

Switch Function:  Mouser seems to just go by whatever the manufacturer put in this field without a lot of QA.  Digikey has it pretty clearly. MOM stands for momentary,  ON-MOM is for Normally Closed, Push to Break switches.  OFF-MOM is for what you usually think of as a button: Normally Open, Push to Make switches.  OFF-MOM-MOM is for DT or oddly SPST x 2. Again, watch the module.

Mounting Style:  How will it be attached? Where’s the solder going to go? Through Hole has legs that go through a hole on the board and can sometimes fit in breadboards. Surface Mount/SMD/SMT are all the kind that rest on the board with no holes. I don’t love that for something that will be pressed often or hard. There are some panel mount tact switches (i.e. the switch will be mounted to the CASE and lead wires will be attached) but those are exclusively the ones that come with built in illumination.  Digikey allows you to indicate some orientation here, too.

Mounting Direction/Actuator Orientation: In your project’s design will the button be pressed from the top (board is parallel to the case surface) or the side (board is perpendicular to the case) or do you need the button to mount to the actual side of the board on the edge?

Other Options: You can buy caps in different colors and shapes, choose the height of the plunger (i.e. stem), if you want the case to be grounded for added protection that is also a choice.  RoHS is the certification that is intended to reduce hazardous materials like lead in electronics.

Price Comparisons: If you are looking at two buttons and they look exactly the same but one is way more expensive than the other look at their data sheets. One may have higher quality metals in their contacts. One maybe better sealed against dusty or wet environments. One may have more clicks per-life-time.  Going back to the manufacturers website and looking at the description for the product series can also give you more insight on what some of the price raising features might be.

Found @ CRASH Space No. 4: Pager Motors as Insects

Pager motors are small motors with a lopsided weight on the end that were developed to shake pagers (link provided for those born in or after the ’90s). They now shake phones, electric razors, toothbrushes, etc.  The particular pager motor for this project was another scrapped-off-the-floor find. Most likely it fell onto floor and hid under the couch during a Mega-Take-Apart excited to be free from a toothbrush.  I made a moth with it.

Which one is alive?

Which one is alive?

The most common quick projects to make with pager motors are vibration robots. That is mostly what you’ll find when searching Instructables.com for pager motor.  The most complete full scale project with etched circuit board and rechargeable batter was the PingBot. It is a great tutorial. Read it and learn.  I also really enjoyed the Tomato Pollinator and Seed Spreader too since they were practical tools instead of just more clutter.  The Instructables most useful to me for making the moth were the Solar Cockroach and the Vibroclip.  If you want to make a tiny car or RC copter, David Cook of Robot Room has written an excellent tutorial on how to remove the the weight.

More pictures and videos of the moth project process are on Flickr.

Moth 1 Facing Camera

 

What I learned

  • Hot glue does not stick to parchment paper (and that is useful)
  • Although the electronics seemed to work perfectly in the breadboard, there really isn’t enough current going through the “eyes” once it all metamorphoses into a moth. Direct sunlight was required, and even that resulted in fiddly behavior.  The photocells are in parallel to reduce resistance, but 2 were not enough.  The motor couldn’t always draw enough current to get the load going and it would stop when the battery got warm.  More photocells (in parallel) would definitely be something to try.
  • Don’t rush soldering. Really. Festina lente. Will I never learn? Bad soldering introduces electrical noise and I really had no margin for that. Also, soldering near hot glue can cause problems.
  • A transistor or mosfet as an amplifier might mean I can still only use two photo resistors, but more other parts… hmmmmm… trade offs.  (An example of a adjustable sensitivity photocell relay trigger)
  • Put the eyes on the TOP of the moth’s head and make sure cells are in the same plane so they both get direct light.

Tools Used:

  • Hot Glue Gun (Shop One, right hand side upper shelves or in the drawers on the bench below)
  • Soldering Iron (Shop One, top of right bench)
  • Wire Strippers (Shop One drawers on right bench)
  • Pliers (Shop One drawers on right bench)
  • Scissors (Shop One drawers on right bench)

Parts & Supplies Used:

  • Hot Glue (BYO)
  • Parchment Paper (my stash but any non-porous, non-heat reactive surface will do)
  • Pager Motor (found on the floor, really)
  • CR2032  Battery (Next time maybe 2, battery box in back left of Shop 1)
  • CR2032 Battery Holder (found in battery box)
  • 26 Gauge Solid Core Wire (wire is at the mid-point of the right benches in Shop 1)
  • Stainless Steel Wire (for antennae,  found in nut and bolt rack near back door in Shop 2)
  • Plastic shopping bag (for wings)
  • 3 white paper clips (for legs)
  • LED Socket (any header will do, optional)
  • 2 10K Ohm Photo Resistors (next time, try multiple per eye – there are some in the little drawer extravaganza in Shop 1)
  • Breadboard for knocking out prototype (My stash. Never leave home without one. )