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July 2, 2009

Ask MAKE: Kids' sprinklers and the CPSIA

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

Bill writes in:

Last year I built a Kid Wash and my kids have loved playing in it. We brought it out again yesterday with the great weather we had over the weekend and my son (age 12) came up with the idea of earning money over the summer by building and selling them locally. It's an easy enough project that I figure he can handle it and it is popular enough with the neighborhood children that he could also have some success in selling it.

However, the new CPSIA regulations have me worried that such a project (however small) will never get off the ground or we'll just be setting ourselves up for legal problems down the road. How do makers who build and sell toys deal with such regulations? Obviously if he was trying to make and sell something hazardous I wouldn't allow it, but how do we encourage such entrepreneurship without exposing ourselves to liabilities.

There was a huge outcry over the CPSIA regulations when they were announced because of their lack of consideration of the costs they would impose on small manufacturers, especially handmakers of one-of-a-kind toys and clothes. The CPSC voted to impose a stay of one year for testing and certification requirements, which expires February 10, 2010. These folks clearly realized there needs to be more thought put into the wide-sweeping rules that would devastate many small businesses. So you still aren't allowed to sell toys with lead paint, small choking-sized parts, etc., but you don't have to have your KidWash tested by a third party for lead and phthalates before selling them to your neighbors. Not until next year, at least.

June 25, 2009

Ask MAKE: Crawl space camera

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

Henry writes in:

There are several ducts and wall spaces I would like to be able to look in. They sell pipe inspection cameras but these are expensive because they are based on fiberoptics. I think an inexpensive video camera and a few LEDs would give you the length of a USB cable and the image could be captured on a laptop. Has anyone made such a thing?

Well, I haven't seen this particular setup DIYed for such a purpose, but I'm sure you could rig up something quite easily. They even make wireless spy cameras small enough to do the job you're talking about. A piece of flexible conduit would work nicely, as you could run the wires for the LEDs down to the handle, but a wooden rod would do the job. Just wire up your LEDs/battery circuit with the battery and switch at the handler's end of the operation, and surround the camera with the LEDs at the business end of the contraption (3 white LEDs wired in series with a 9V battery should do the trick).

When I was a kid, my parents took on a home remodeling project that ended up exposing the long-hidden colony of carpenter ants in the wall above the old sliding glass door. If they had one of these things, it probably would never have rained ants all over my dad! If you find anything cool in there, let us know! Here are some projects to get you started:

RC boat with cheap wireless video

From the pages of MAKE, Vol. 14 (Optics):

Living Room Baja Buggies by John Mouton. With wireless cameras on board, these radio-controlled racers give you virtual reality telepresence; Living Room Baja Buggies in the Digital Edition.

Covert Spy Sunglasses by Kip Kedersha. Record what you see and hear with these low-cost stealthy sunglasses; Covert Spy Sunglasses in the Digital Edition.

June 18, 2009

Ask MAKE: surplus TVs from the DTV switch

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

Twitter users @threefourteen, @klaatu, @dcwilson303, @digitalcaffeine, and others all had the same thing on their minds this week and asked "What do we do with all the TVs flooding thrift stores because of the DTV conversion?"

Well, after taking a break to re-watch one of my favorite video art pieces, Media Burn by Ant Farm (above), we've come up with some advice. First off, you can keep your TV in use with a digital receiver, for which you can even make your own antenna. Failing that, you can still watch DVDs on your old set, making them perfect for the movie den, or for donating to your local schools (call and ask if they want them first). Whatever you do, don't throw it in the trash, that old box can contain lots of lead. Recycle it. Now on to repurposing:

Make some art:

get a cheap video camera, make a video loop, and experiment with interference patterns
stack, pile, and create towers of video ala Nam Jun Paik (RIP; pictured above top)
use the TVs as period props for films and plays
make that video installation you've always wanted to
lower its resolution for some pleasing ambiance
burn in some subliminal messages

Take the thing apart:

watch out for the large high-voltage capacitors that can remain charged inside!
teach your kids how cathode ray tubes work
create a video highlighting the "little city" (above)
scavenge it for parts
make a cat bed or fish tank
create a shrine to your favorite cancelled show

Reuse the parts:

make a floating halloween head
convert the old case into a bar
try out the YBOX, an internet appliance for your TV (pictured above)
don't forget your Arduino TV!
try your hand at circuit bending (be extra careful and read up before opening it!)

Have some TV ideas? post them in the comments!

June 11, 2009

Ask MAKE: For engineering faculty

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

Michael Willits wrote in to us on Twitter, "Do you have suggestions for how engineering faculty could see Makezine.com as a valuable educational resource?" A few ideas come to mind.

Assign a re-engineer project

You could assign your students to search here on the site for an open source DIY project, then take the plans and re-work the design. This would work for all fields of engineering and you could even have them release the new, improved project plans back out there to the community online. It's not about finding problems in other people's designs, it's about building on the group of dedicated makers and their innovative projects. Check out the archives in the following categories: electronics, furniture, computers, flying, open source hardware, robotics, science, and wireless.

Give a resources-limited problem

Create a project where the materials for completion are limited. It can be a software or hardware limitation, and could vary from person to person, say, "whatever you have in your garage," or "the following electronics components only." Send them here to look for inspiration.

Get feedback

If your students are keeping a public log of investigations (in blog form or otherwise), they can submit their work here using this page or to the Makezine forums. Getting a project or problem here on the blog is a great opportunity to expose student work to a wider audience that loves to give constructive feedback. Keeping a project blog is a great way to connect with other engineering students as well as interested industry members from around the country and world.

Use projects from the blog as case studies

A big part of engineering is communicating your ideas effectively. With your students, go over sample projects featured here and analyze their method of presentation and public response. Find and identify smart presentation methods and also places to improve. We frequently feature projects for the simple reason that they are documented extensively and completely. Check out our archive of Instructables as well for this one.

Have a suggestion for Michael? Are you an engineering professor using our site as an educational tool? Please share with us in the comments!

Photo above is some amazing papercraft by Haruki Nakamura.

June 4, 2009

Ask MAKE: Kid's birthday success story

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

Kari in Austin has a very creative son, Sam. He's a "maker in the making," you could say. CRAFT contributing writer Rachel Hobson put me in touch with Kari for my weekly Ask MAKE column because she was looking for the perfect gifts to stock her son's birthday toolbox. Well, look how happy Sam is, and look at his awesome loot! Over on Flickr, she has a nice breakdown of what goes in the toolbox. Thanks to everybody that gave great suggestions for Sam's first toolbox!

More:

Ask MAKE: Kid's first toolbox

May 21, 2009

Ask MAKE: Kid's first toolbox

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

This week's question comes to us via CRAFT contributor Rachel Hobson. Her friend Kari is mother to a "true maker in the making." Kari writes:

Sam's birthday is a week from Sunday and I'm thinking of putting together a toolkit/box o' gadgets for him. Things to help him take stuff apart, things that he can do little experiments with, stuff like that. I'm thinking of a tiny screwdriver, electrical tape, maybe a hammer. He already has a tape measure. I don't know what else would be cool and fun and good for a seven-year-old. I want this to be the "big" item for him, a big toolbox with a bunch of wrapped things inside.

We passed this question around on the Make: Online Editors mailing list, and got a lot of neat suggestions. I'm sure these won't all fit for Sam's birthday, but at least its a jumping-off point!

third hand tool with magnifying glass (for holding and inspecting stuff)
small flashlight or head-mounted light
needle-nose pliers
gaffers tape (not as messy as duct tape)
safety goggles
wire cutters
ruler or square
multimeter
Maker's Notebook (we'll toss that one in for free, happy birthday, Sam!)
zip ties
some junk to take apart (CD drive, old radio, etc.)
wire nuts
battery tester
battery clips
battery tester
tire pressure gauge

If you have any suggestions for a seven year-old's first toolbox, please post them in the comments below!

Above image is cc-by-nc-sa by Flickr user Austin ampersand Zak.

May 14, 2009

Ask MAKE: Summer camp bugle automation

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

YMCA summer camp director Don Jennings writes in:

Summer camp runs on signals - bells, bugles, claxons, etc. And though the old-timers grumble, the days of folks pulling a rope, blowing a horn or turning a crank are mostly gone. Camp signals have gone digital, and therein lies the challenge.

Our current system for playing bugle calls is Rube Goldbergian in the extreme. I won't even attempt to describe it except to say it involves an answering machine tape, a PA system, bullhorns, and an entire software suite of home management software. All of this to run 20 seconds of bugle, 8 times each day. It's an embarassment of Byzantine seat-of-the-pants hackery that only works part of the time.

In my 50% geek heart I know there must be an elegant, inexpensive way to play digital bugle calls at specific times of the day, for discrete durations. There just *has* to be. And so my appeal to your readers.

Can you or your communities offer any advice? A solution would garner the enthusiastic gratitude of dozens of summer camp communities.

The camp runs on Windows XP, and a solution would have to be comfortable on that platform. Do you have any ideas?

There are tons of automation programs out there. Mac OS X has Automator which works with AppleScript, you can make cron jobs on a Linux server, but I'm going to suggest you use Windows Task Scheduler for your situation. It's free, already on your camp's Windows XP machines, and should be relatively easy to set up. That said, I'm sure there are free utilities out there you could download to do this as well, but I'm not a frequent enough Windows user to be able to suggest any. If any readers know of something that would work , please post it in the comments!

My main squeeze, Alex Schlegel, helped me figure this one out for you. You can program the Task Scheduler to play a sound file however often you want throughout the day, every day, using Windows Media Player (the older version, mplayer2.exe, because the newer wmplayer.exe doesn't respond to the /close command line argument). You can schedule a task to, at regular intervals, open the media player, play the sound, then close. This does not have to be a dedicated machine, but you'll have the sound hooked up to the PA system, so whatever computer you use should have its user interface sounds (system notifications, etc.) turned off.

You can use any one of the Windows Task Manager tutorials available online to get yourself acquainted with the program, but since you're 50% geek I'm sure you can play it by ear. Access it through your control panel, and create a new task. Select that you want it to occur daily, with a start time when you want the first call to happen. Then hit "Advanced" to repeat the task throughout the day, with a finish time when the last sound will happen. Alex took a few screenshots to help out.

Once you create a new task, it will open a wizard that will make you pick a program to run from a list (at this point it doesn't really matter what program you pick, but to be on the safe side you might browse to "C:\Program Files\Windows Media Player\mplayer2.exe"), and select how often you want it to occur (once per day in your case), but on the last page there's a checkbox that says "Open advanced properties for this task when i click Finish." This will open the screen that allows you to input the command line text to play the audio file:

"C:\Program Files\Windows Media Player\mplayer2.exe" /play /close C:\Windows\Media\tada.wav

Replace the path to "tada.wav" with whatever bugle sound you want (a 20 second mp3, for example). If you want the sound to play at non-regular intervals, you'll have to create a task for each bell throughout the day. Once you get it up and running, though, you should hardly have to touch it.

The photo at the top is the "time for thought" area at the summer camp I attended as a child (Windham Tolland 4H in Pomfret, CT), taken by my camp buddy Natalie Carter.

May 7, 2009

Ask MAKE: Small space workbench

Justin writes in:

I only have a small space available in my apartment, but I would love to have a workbench area. I really miss having a garage where I can setup a full size work bench and leave projects out. Currently I use my computer desk or kitchen table, but I have to put everything away once I'm done working for the day which is a huge hassle. I would love to see other Maker's small-space inside workbenches.

Justin, I know exactly what you mean. In my first apartment, my room was so small that I had to sit on my bed to use my desk; the (small) furniture went wall to wall. When working on electronics projects, I often ended up with components or clipped leads in the sheets, not to mention all those restless nights when I checked email every time I tossed or turned! It's important to have a dedicated workspace where you can leave in-progress projects. You may not even have enough space to pull off the Tight-Fit Workbench from MAKE, Vol. 10. Here's what I recommend:

Use your wall space

Pegboard is great for holding tools on the wall, where they don't take up any floor space; put it wherever you can. Also, attach shelving to your walls to maximize the vertical space you have. I also love the little wall-mounted tool rack you see at electronics outlets.

Keep as much off your desk as possible

Get a pull-out keyboard/mouse tray. That way, the space in front of your monitor can be used for building things. I just took this very advice, and I'm surprised at how much of a difference this small change made. Ikea sells them for ten dollars. Hang lights from the ceiling, don't clutter your desk with lamp bases. If you use a laptop, get a stand to raise it off the surface of your desk and use an external keyboard (on the pull out tray, of course).

Make a dedicated workbench (if you can)

When all else fails, see if you have room for even a small dedicated workbench (think shallow and long, even a low shelf mounted to a wall). Adding another tabletop to form an "L" with your current computer desk is ideal, but any horizontal plane you can claim for your projects will suffice.

Do you have advice for Justin's workbench? Post them in the comments.

Ask MAKE is a weekly column where we answer reader questions, like yours. Write them in to becky@makezine.com or drop us a line on Twitter. We can't wait to tackle your conundrums!

April 30, 2009

Ask MAKE: Voltage annotations

Kevin asks:

What do all those little subscript letters and numbers after V on circuit diagrams mean Vcc, Vee, Vss mean?

I have to admit, I didn't really know the full answer to this one, so I looked it up. I found a page on the solarbotics website explaining the whole shebang: Vcc and Vdd mean that that point in the circuit is directly connected the power source, and Vee and Vss mean that point it is connected to ground. It went on to say:

Apparently this terminology originated in some way from the terminals of each type of transistor, and their common connections in logic circuits (i.e., Vcc is often applied to BJT collectors, Vee to BJT emitters, Vdd to FET drains, and Vss to FET sources). This notation then carries across to integrated circuits -- TTL ICs were originally based on BJT technology, and so often use the Vcc / Vee terminology; CMOS ICs are based on FET technology, and so often use the Vdd / Vss terminology.

The absolute distinctions between these common supply terms has since been blurred by the interchangeable application of TTL and CMOS logic families. Most CMOS (74HC / AC, etc.) IC data sheets now use Vcc and Gnd to designate the positive and negative supply pins.

Image is a snippet of the schematic for SparkFun's Blue SMiRF.

Have you got additional information? Post it in the comments! Have a question for Ask MAKE? Shoot me an email at becky@makezine.com or drop us a tweet! We'd love to answer your questions on anything MAKE-y.

April 23, 2009

Ask MAKE: Silicone sticks to what?

Matt asks:

I'm interested in making a silicone mold, and I'm wondering what sorts of things the silicone will stick to and what sorts of precautions to take to prevent it from sticking? I'm making a mold of a plastic figurine.

Well, you have to assume it will stick to anything. If you're using Polytek PlatSil or TinSil, you'll want to use a non-silicone based mold release (like PolEase 2500), and spray shellac will work in a pinch. SIlicone sticks to itself, too, so be sure to coat the different pieces of your mold in the release agent before pouring multiple parts. When in doubt, give the folks at Polytek a call; they're really helpful on the phone and will work with your specific project to make sure you're using the right materials and processes.

If you're unfamiliar with moldmaking in general, check out our primer in MAKE, Vol. 08 by Mythbuster Adam Savage. You can preview the article in the Digital Edition.

If you have a question for Ask MAKE, send me an email at becky@makezine.com or tweet at us!

April 16, 2009

Ask MAKE: Navigating Maker Faire

Amy Zimmer from Sebastopol, CA writes in:

I would love to go to the maker faire in San Mateo--but crowds flip me out! Do you have any suggestions or must sees for navigating for a crafty mostly gift giver type crafter (and maybe her two girls, ages 10 and 14)?

I think each of us experiences a bit of enochlophobia or agorophobia at some point during Maker Faire; there are just so many people! Well, Amy, you should definitely check it out, it's a great event for the whole family, and here are some tips that might make the experience more enjoyable for you and everybody else who's not at piece in a crowd of tens of thousands:

Buy your tickets in advance

Avoid the ticket line by buying your tickets online in advance.

Check the Maker Faire site regularly

In the weeks before Maker Faire, there will be more and more information published to the Maker Faire site including schedules of demos, makers who'll be attending, and information about transportation to/from the Faire. This will help you know what to expect to see, which should make the visit a little less overwhelming

Make a loose plan for the day

Using the schedule provided online and onsite at the Maker Faire, decide which demos and events are a must for you and your girls (diet Coke and Mentos at 12:30? Soft circuit demo at 11am?), and then plan your day around those. Know which maker and crafter booths you want to get to, and allot time to get to them between time-specific events. By all means, also allow time for unexpected things to catch your eye, but having a plan of attack can help you feel in-control.

Shop early

If you plan to shop in the Maker Shed and Bazaar Bizarre, do it early in the day. Sure, you'll have to carry around your purchases with you, but this is when the crowds are smaller in these parts of the Faire.

Find some quiet time

This one is the hardest tip to actually implement, but it can certainly help. Find a shady grassy spot to eat lunch or otherwise relax and reflect. Drink plenty of water throughout the day to stay hydrated (oh, what a difference it can make in your energy level and mood)!

I hope those tips are helpful to you, and that you'll come out and see us at Maker Faire! Have you been to Maker Faire before and have tips for Amy? Share them in the comments below!

If you have a question you'd like answered here on Ask MAKE, drop me an email or tweet at us!

April 9, 2009

Ask MAKE: Grandchildren starter projects

David writes in:

I am interested in fooling around with LEDs. Nothing fancy I just want to learn some basic stuff, and build some easy circuits. I am 65 years old and have some time on my hands so I want to explore these devices. Could you send me a list of some elementary school level books? I have a couple of grand children that I want to play with; and, I think we could have fun and learn some interesting things together. I don't know what aspect of this technology will interest them, but maybe we will build something that we can attach to an old cd player that will change colors in conjunction with the music.

Well, David, I don't know about elementary school level books, but I can certainly suggest some kits to start you and your grandkids off. LEDs are a great place to start. They don't take a lot of background knowledge or equipment to get started. A good first project is to make some LED throwies. All you need are LEDs, coincell batteries, magnets, and tape. You can get LEDs and batteries online, or from RadioShack or Fry's Electronics if there's one nearby. From there move on to blinkybugs and vibrobots, and then maybe the Sparkle Labs kit for learning electronics, which comes with an excellent booklet full of illustrations and easy-to-follow instructions for popular and simple circuits. As for making an LED blink in time with music, you could follow this Instructable. You might also like playing around with 555 tmers, as they're pretty easy to get going, too. There's a great article on them with sample diagrams in MAKE, Vol. 10. I'm so glad you're excited about building things with your grandkids!

April 2, 2009

Ask MAKE: Siphon for homebrewing beer

Alex asks:

I've brewed beer at home three times, but one thing has always proved to be a problem: How do I get a siphon going well for moving my cooled wort into my primary fermenting bucket, and then for bottling? When I put my mouth on the tube to start the flow, it de-sanitizes the equipment I went to great length to clean, and the flow often stops, making me have to repeat this process. It's very frustrating! I'm sure there's a better way.

I've also brewed beer a few times at home, and this part was tricky at first. You really shouldn't put your mouth on the tube, as it introduces bacteria to the cooled wort, which could spoil the whole batch. I found a video (above, from homebrewingvideo.com) which illustrates an effective way of starting a siphon that works remarkably well. Basically you start the siphon with water from the sink, with the racking cane in a vessel of sanitizing solution. Hold the tubing up to the running faucet water until water starts flowing into the sanitizing solution vessel, then stop the flow with your thumb over the end of the tubing. Then start the siphon by holding the end of the tube low in the sink (lower than the sanitizing solution vessel) and letting go with your thumb. Liquid will flow from the vessel into the sink, and once it starts going well, cap the tubing with your thumb once again. At this point it's safe to lift the racking cane and tubing assembly out of the vessel (keep your thumb over the end of the tubing, and the suction will prevent liquid from exiting the bottom of the racking cane), moving it over to your wort container. With the end of the racking cane in the wort and the end of the tubing lower than the wort vessel, release your thumb, siphoning the water into a waste container (or in the grass if you're in your backyard) until the wort starts coming through, at which point you can move the siphon tubing to drain into your fermenter or bottle. This is a long convoluted explanation of the easily demonstrated method shown in the video, so be sure to watch that too. Happy brewing!

If you've got a question for MAKE, send it my way! Anything goes: photos, video, schematics, you name it. Send questions to becky@makezine.com or hit us up on Twitter.

March 26, 2009

Ask MAKE: Large LEDs and building your electronics stash

Tim writes in:

What are the reasons we see light bulbs made up of lots of small LED's instead of one large LED?

As Collin showed us in his excellent video about the subject, LEDs pass electricity through "dies," or little chips cut from a larger wafer of semiconductor; there is just a small active area that's actually lighting up, which is then reflected out in the desired direction. Engineers try to make the most efficient LED possible, which is linked to the size of this semiconductor as well as the heat it puts out, among other things. There is such a thing as a multi-die package, which puts more than one piece of semiconductor inside the same plastic casing. My favorite electrical engineer, Matt Mets, found me this interesting article comparing the efficiencies of single-die and multi-die packages for LEDs. Essentially, the maximum usable size of the semiconductor is limited, and there's a limit to how many you can cram into one lens before the thing generates too much heat. On the practical side of your question, the market is just now seeing a boom in these "bulbs" containing many LEDs, like the one pictured above (image from Treehugger). The product designers for these things are buying off-the-shelf components and putting them together into a product, not engineering new LEDs... yet. We're able to see a massive reduction in energy consumption with these LED bulbs when compared to incandescents, so the demand for an even more efficient model (perhaps using multi-die LEDs) hasn't quite caught up to us yet. The takeaway: bigger isn't always brighter!

Young maker Justis writes in:

I've just started out in electronics and I want to make some cool stuff! but alas, being a kid and all, I don't have much time to bike to radioshack every time I need a resistor. How do you recommend I start gleaning things for projects?

Simple: you've got to build up a stash! Components aren't that expensive, especially resistors. I'd recommend asking family members for gift certificates to Sparkfun, the Maker Shed, and even Amazon, which all carry excellent components and kits, and they'll mail them right to you, no bike-riding required (work with your parents to ensure you're buying form a reputable site). If you come across older devices at the thrift store, like VCRs and the like, they often contain full-size (not surface-mount) components that you can remove while you practice your de-soldering skills. When I was a kid, I was really into baking, so for every gift-giving holiday, I'd ask for a different item that I couldn't afford myself, namely a stand mixer. If you make a wish list for those who might shop for you, include web addresses for particular products to ensure your non-savvy relatives get you the things you really want. To start with, I'd highly recommend the DIY Design Electronics Kit by Sparkle Labs. It comes with a great starter assortment of many different types of components in common varieties, so you won't have to ride over to RadioShack quite so often. Show us what you make!

If you have additional advice for Tim or Justis, leave it in the comments! And if you have a question for MAKE about a project you're working on, concept you're trying to understand, or anything else related to the complicated life of makers, drop me a line at becky@makezine.com (or record a video, tweet at us, etc.).

March 19, 2009

Ask Make: New column!

We're launching a new column here on Make: Online called Ask MAKE. The idea is pretty simple: you write in questions, and we answer them! It can be about anything from electronics to recycling to questions about the magazine or Make: Online. Ask us anything about everything we usually cover in print and online. And you can ask us in whatever medium you'd like, too. Email me at becky@makezine.com, send us an @ reply or DM on Twitter, submit a page on your site highlighting the problem, record a video, send a carrier pigeon, whatever floats your boat. We'll answer your questions right here, every Thursday. Oh, and if you have a craft-related question, check out our sister column on Craftzine, Ask CRAFT.