Geek Dad: Awesomely Geeky Projects and Activities for Dads and Kids to Share

by Ken Denmead

  WARNING: This is not a practical project. It would be easier to build a rope swing with just rope. But it wouldn’t be as cool. Also, keep this out of the rain. The phone books won’t last long if they get wet or suffer otherwise extended exposure to the elements. This swing should be built to be easily taken down and stowed away between uses.

  What we’re doing is taking the classic idea of a rope swing and adding the friction twist by putting two interlaced phone books into the hanging assemblage. If you haven’t seen the episode of Mythbusters, the simple science here is that, if you take two phone books (and who really needs their phone books these days?) and interlace the pages as you would shuffle a deck of cards, they can’t be pulled apart by any practical means.

  How does it work? The simple answer is friction. The friction between individual pieces of paper is negligible. However, when you interlace the pages of two phone books with hundreds of pages in each, the cumulative effect is stronger than glue, and you won’t be able to pull them apart with anything less than a couple of tanks (hence the “practical” caveat above).

  INTERLACING THE PHONE BOOKS

  This is the long, slightly boring part of the project. You want to start with two phone books of approximately the same size (identical if you can get them). Set them in front of you on a table, with the binding sides facing out. Imagine shuffling them like a deck of cards: You’d simply pick up the inward-facing, loose sides of the books, bring them together, and shuffle.

  Unfortunately, for this project, it takes a little more work than that.

  Take the books and fold everything outward, until all you have are the back covers facing inward. Bring the two books toward each other until one cover lays over the other by at least half its width. Then start leafing pages over, first one book, then the other, alternating as you go. Do this until you have interlaced all the pages.

  BUILDING THE SWING

  Next we’re going to incorporate the phone books into the swing. We will build reinforced brackets so we can tie the rope for our rope swing to the spines of the phone books.

  STEP 1: Cut 4 strips of plywood (½ inch or thicker) 3 inches wide and as tall as each book to sandwich the un-interlaced ends of each of the phone books.

  STEP 2: Take one side of the interlaced phone books and sandwich the spine with two strips of the plywood. Hold the pieces of wood in place with a clamp.

  STEP 3: Now drill three holes through the plywood/phone book sandwich, spaced evenly across. The holes will be two different sizes. The center hole should be about the diameter of the rope you’re going to use (probably ⅝ inch to 1 inch). The other two should be sized to fit the bolts you’re going to use to hold the brackets together, perhaps ⅜ inch or so. Go ahead and drill, and bolt the brackets together, leaving the center holes open on each end of your assembly.

  SETTING UP THE SWING

  STEP 4: Figure out where you’ll hang the swing: off a play set, a sturdy tree branch, or some other overhanging anchor point. Decide how long your rope is going to need to be, roughly. Assume you’ll need a knot at the bottom for the seat to rest on, enough length such that the seat will be suspended two to three feet off the ground at the lowest point of the swinging arc, and enough at the top to tie it off at the anchor point. This should be a conservative estimate; you can always trim it later if it’s too long.

  Your choice of rope is important. You’ll need something fairly thick and strong. A heavy climbing rope can be a good choice, as you’ll want to be able to knot it relatively easily.

  STEP 5: Your first piece of rope will go from the “top” side of the phone book assembly to the anchor point where it hangs. Figure out what you think that distance will be, then triple it to give yourself some length to work with. Feed the rope through the large center hole in one bracket, pull it even so the ends meet when held straight up from the books, and tie a good knot (I’ll leave it to your Boy Scout skills or Internet research to determine the right one).

  In my version of this build, I hooked the knotted end to a heavy-duty carabineer, and then found a heavy-duty hook I could drill into my anchor point. You may have to adjust depending on your anchor point, available tools, and hardware, but I have faith you can figure it out.

  STEP 6: Hang from the anchor what you’ve got done so far, and try testing it with your weight. Isn’t friction amazing?!? Next measure the distance from the bottom of your assembly to where you want the seat to be at the bottom of the swing’s arc. You have two choices now: Use either a single length of rope tied off to a carabiner or a metallic ring hooked through the bottom hole of the phone book assembly.

  STEP 7: Measure the rope so you have a good foot below the seat point. Build your seat. The simplest is to cut out a square of thick plywood, or sandwich a couple layers of thinner plywood, and drill a hole through the center to pass the rope through. Knot the rope both above and below the seat to keep it in place, making sure the knots are tight and that they’re big enough not to pass through the hole.

  And with that, you’re done! Let your kids try it, even try it yourself, and tell everyone who comes over how the only thing keeping it together is the magic of friction!

  (Be sure to bring it in the house when you’re done—getting it wet would be bad.)

  AWESOME ACCESSORIES

  Smart Cuff Links

  Geek culture tends to be, shall we say, a casual culture. We tend to be more comfortable in khaki shorts and superhero T-shirts than suits—and that’s just at work. But there are a few times in a geek’s life when fancy dress (and we’re not talking cosplay here) may be required. But even if you or your kids have to dress up, that doesn’t mean you have to lose your geek cred.

  All the parts to this project are available at your local electronics or computer store, though if you’re a geek worth your salt, you very likely already have them. Obviously the crimper is the most specialized piece of equipment, but crimpers can be found pretty much everywhere (I’ve seen them in Home Depot, RadioShack, and Target).

  1. For one cuff link, measure out about 3 inches of the twisted-pair wire.

  2. Untwist the ends a bit so they’ll be easier to get into the connector.

  3. Feed one end of the pair into the two available holes on one extreme side of the connector.

  4. Feed the other end into the hole on the opposite extreme end of the connector, and crimp per the instructions that come with the tool. This will create about a ¾-inch loop of wire coming out of the back side of the Ethernet connector.

  5. Trim a 4-inch piece of twisted-pair wire, fold it in half, and twist together into one thicker length.

  6. When you’re ready to put the cuff link on, feed the loop from the Ethernet connector through the French cuff in just the way you would the post of a traditional cuff link. Feed the doubled-over 4-inch length through the exposed loop, and twist over so the cuff link stays in place.

  Repeat this with another connector to make a second cuff link to fill out your pair.

  An Even Cooler Idea

  If you are an advanced Ethernet cable installer (meaning you know how to crimp connectors on either end of a length of cable), put an RJ-45 connector at one end of a cable, and the RJ-45 jack at the other. Depending on the length of cable, it could be used as a bracelet, stylish tie, belt, or ID card lanyard.

  The end result of this project is a formal accessory for the geek who is truly secure in his technophilia. Whether it’s the winter ball or a dance, New Year’s Eve, or even a (your?) wedding, this simple bit of whimsy should see you through.

  Light-up Duct Tape Wallet

  GeekDads tend to do a lot of technical stuff with their kids. Beyond just video games, we love to learn programming, or go geocaching, or hack roadway message boards to flash lines from Tron at passing motorists (okay, maybe that’s just me). All very technical geeky activities. And we know geeks can get into crafts as well, from crocheting dice bags (page 157) to cosplay costumes. But what about melding crafts and technical geekery into one pro
ject? Oh, that’s easy!

  Tape as a textile, you ask? Why, of course! Duct tape—another WWII military invention brought to use in everyday life afterward—is fabric-reinforced for strength and has a rubber-based adhesive that resists the effects of moisture, making it a very handy material for a variety of textile projects (there are a slew of Web sites dedicated to various duct tape craft projects). Indeed, the duct tape wallet itself was not invented for the GeekDad book, but the little variation included here was, and with it, we turn the geek factor up from 10 to 11.

  There are two halves to this project—the wallet itself and the light module. We’ll start with the wallet.

  MAKING THE WALLET

  To make the wallet, first collect your materials. Of course the primary material is duct tape. For the purpose of this project, we’ll stick to just classic silver-backed duct tape, but there are a variety of colors available at your local hardware store, so if you want to get creative in the future, go crazy.

  STEP 1: You’ll also need a surface to work on. A plastic cutting board is very effective, because while the tape will stick to the board, it can be pulled off fairly easily and still retain most of its adhesive. That will be key for this project. A ruler is not vital since you can work from a dollar bill for your dimensions and eyeball things generally, but a straight-edge is very handy. And if you’re a stickler, use a ruler, for I’ll give you rough dimensions all the way through. For this part, you’ll need that box cutter or X-Acto knife, which will cut through the duct tape like “buttah.”

  What we’re making here is a simple billfold, and you can even use one you have on hand as a guide.

  1. Start by laying three overlapping rows of tape on the cutting board to create a rough shape at least 7½ inches wide by 4½ inches tall.

  2. Lay your dollar bill (which is 2½ inches tall by 6 inches wide) on top and trim the tape sheet so that it is about ¾ inch wider than the bill on each side, ½ inch clear at the bottom, and 1½ inches on top (see, that makes 7½ by 4½ inches). Try to get nice clean edges.

  3. Now carefully peel the whole sheet off the board (use the knife to get under one corner, and then slowly pull the tape away) and lay it adhesive side up.

  4. Tape over the sheet with new rows of duct tape, making sure you go at least ½ inch wider all the way around.

  5. Trim this cover layer so that it is ½ inch wider and taller, then cut the corners at 45-degree angles (kind of like any piece of paper in Battlestar Galactica).

  6. Flip the whole piece back over, then fold the overlapping edges over and stick them down so that you end up with a nice sheet of double-backed duct tape—the perfect waterproof wallet material.

  STEP 2: Now we’ll start on the inner pouch that’s going to hold the electronics package (sounds very spy tech, doesn’t it?). Our guide for the size of the pouch is the size of the battery holder. I’ll talk about the electronics materials later in this project, so you should read the whole thing before starting. However, the battery holder is a simple AAA module like you’d find in many toys or other devices. It’s not much bigger than the actual battery, so you can approximate the size of the pouch based on that information.

  1. We’re going to make a two-sided tape sheet just like the first one, but sized so that, if you rolled the battery holder up in it, the sheet would wrap around it once, with about ½ inch extra (call it 2 inches tall by 3 inches wide).

  2. What you’re not going to do like the last time is to make a 45-degree corner cut and seal all four sides. Instead, trim the corners square (at 90-degree angles) and seal just the top side by folding the flap over.

  3. On the bottom flap, do a little more trimming so it has three serrated-looking tabs. These will become the bottom closure of the pouch.

  4. Using the battery holder as your guide, roll the pouch up so that the left side tab seals it up into a tube shape, leaving the right side tab still unadhered.

  5. Fold the bottom serrated tabs in on themselves to create the wallet’s bottom (there will be a bit of the sticky side facing into the interior of the pouch—this is intentional, to help hold the electronics in place).

  STEP 3: You now have a pouch with a sticky tab on the right side, which we’ll use to attach the pouch to the inside of the wallet. We’ll do that now, by applying it to the first sheet we made. On the left side of the sheet, set the pouch with the tab on the left. The bottom of the pouch should be ½ inch from the bottom of the sheet, and the sticky tab should fold over and behind the left edge of the sheet.

  STEP 4: Next we’ll make the sheet that finishes our wallet. This sheet is the inside of the billfold, so it should be a little smaller—say 3½ inches. But because it has to allow for the bulk of the pouch inside, it needs to be a bit longer; try 7¾ inches wide. When you’ve applied the second face, and flipped the sheet back over, trim the top corners at 90-degree angles, and the lower corners at 45-degree angles. Fold the top flap down to seal the top edge.

  STEP 5: Now take your first sheet with the pouch and flip it facedown. Line up one lower corner and side edge with your new sheet (make sure the first sheet is oriented so that the open end of the pouch is facing up toward the finished edge of the new sheet). You should be able to fold the side sticky tab of the new sheet over the edge of the old one. Then line up the first sheet’s bottom edge with the inside edge of the new sheet so the bottom sticky tab can fold up and over. Finally, line up the other side edges and fold over the last sticky tab so that you have attached the new sheet to the first sheet, with the pouch on the inside.

  STEP 6: You now have the basic billfold with a pouch inside. If you want, you can add another inside sheet, perhaps in a different color for a nice accent, and slightly shorter than the inside wall of the billfold, as a pocket for credit cards and ID. Those sorts of additional features I’ll leave up to you and your kids’ creativity.

  BUILDING THE ELECTRONICS

  The electronics package is where you can make this really geeky, and where you have the chance to play with the materials you can find. I went with some cool items I dug up at my local Frys Electronics, the handiest of which was the bulb. While we geeks like to dabble in all things LED (as you can well see elsewhere in this book), sometimes the simplest alternative can be the best and easiest to deal with. When I saw these replacement bulbs for Mini Maglites that were specifically designed for use with a single AAA battery, I was happy. What’s easier than battery/bulb/switch to build a circuit for something like this?

  Admittedly, this could be done a bit geekier, and more streamlined, with LEDs and a CR2032 battery, but I’ll leave that up to you to find and figure out.

  Where I did go geeky was with the switch. While there are numerous neat little switches available on the aisle at my store, when I saw they had a small selection of mercury switches, I just had to use one!

  Assembly of the electronics is a commonsense process, building a circuit from the negative end of the battery holder, through the switch, the bulb, and then to the positive end of the holder.1. Take the battery holder (sans battery for the time being) and attach one lead of the mercury switch to the negative end (usually the end with the spring). You might want to use a small pair of needle-nose pliers to help manipulate the wiring, and make sure you wrap the wire up in such a way as to keep things from shorting.

  2. You can use small strips of duct tape to hold the switch to the side of the battery holder. Make sure the mercury switch is positioned so that, when the wallet is “up”—meaning that the open side for looking in to see the contents is facing toward the sky—the switch is activated (the blob of mercury is on the “bottom” of the bulb where it touches the two contacts to close the circuit).

  3. The other lead of the mercury switch is attached to a small length of wire, so the circuit can reach the top/positive end of the battery holder. Step 1

  Step 2

  Step 3

  Step 4

  Step 5

  4. At the top, connect one lead of the lamp to the wire, an
d the other to the positive lead of the battery holder.

  5. A few twists of the wires, and some more small strips of duct tape to hold everything together, and you have a circuit.

  6. Put the AAA battery into the holder, and then test it by turning it upside down and right side up to make sure the bulb turns off and on.

  Just slip the package into the pouch inside your wallet. The bulb should just stick out of the top of the pouch, but should not clear the edges of the wallet itself. Put a few dollars into the billfold, and marvel at your lighted wallet!

  Please Remember!

  There are two caveats that go along with this design. First, for safety, this should be a front-pocket wallet, since both the bulb and the switch could be crushed if you sit on them. Second, by using the mercury switch, when the wallet is in your pocket, it needs to be top side down so the light stays off. Thus, keeping coins in the wallet may be a bad idea.

  Crocheted Dice Bag of Holding