Make Magazine - Volume 33

CD

soldered connections with heat-shrink E
tubing, and shrink it in place.

Remove the nut and washer from
the rheostat, and insert it through
the hole in the enclosure from inside.
Fit the indexing tab into the alignment
hole, put the washer over the shaft,
and gently but firmly tighten the nut
with a wrench. Fit the knob onto
the shaft and secure it in place by
tightening the setscrew with a small
flat-blade driver (Figure C).

3.MOUNT THE F
AUDIO POT
4.ADD THE
This knob controls the intensity of PHOTORESISTOR
the tremolo effect. First, cut the shaft
to the same length as the rheostat These photoresistors come in packs of 5
using a hacksaw. Then turn the pot all with big, medium, and small sizes. We’ll use
the way “down” (counterclockwise) one of the medium-sized resistors and an
and file a small flat surface on the side LED holder to mount it.
directly opposite the indexing tab.
This will ensure that the shaft always Remove the rubber insert from the LED
turns with the knob (Figure D). holder. Guide the legs of the photoresistor
through the holes in the insert until the
Again, identify the pot’s “high” resistor body is seated against the insert.
contact using the resistance setting
on your multimeter. Solder a 4" length Cut two 4" lengths of green wire. Strip
of wire to this contact, and then bend about ¾" of the insulation off each end, twist
and solder the other 2 contacts to a the copper strands together tightly, and tin
second 4" wire. As with the rheostat, one end. Solder the tinned ends to the photo-
the resistance across the 2 contacts resistor leads. Slip a piece of 2mm heat-shrink
should go from high to low as the tubing over each wire so it completely covers
knob is turned “up” (clockwise). the solder joints and exposed photoresistor
leads. Shrink it in place (Figure F).
Mount the pot in the enclosure,
with its indexing tab in the alignment Push the insert back into the LED holder
hole. Secure the shaft in place with its until the photoresistor is seated in the open-
bundled flat washer and nut, tighten- ing. Put the LED holder through the enclosure
ing gently with a wrench (Figure E). panel from the front, and tighten down the

makezine.com 99

PROJECTS OPTICAL TREMOLO

hex nut and split washer from behind G
using a wrench (Figure G).

5.MOUNT H CAUTION
THE MOTOR I
Don’t overtighten the
The hub we’re using to mount the screws, or you risk
sweep disks has a 3mm arbor hole, stripping out the metal
but our motor’s shaft is only 2mm in the motor casing.
across. A short section of ink tube
from a ballpoint pen makes a per- L2+ COM L1+
fect adapter. Just push the shaft of L2– COM L1–
the motor into the tube and cut off
the excess with a sharp hobby knife
(Figure H).

Solder a 3" length of wire to each
of the motor’s contacts. Then pass
the motor shaft through the hole in
the enclosure from the inside, and
secure the motor in place with a
#4×¼" wood screw in each of the
2 mounting holes (Figure I).

6.MOUNT J
THE SWITCH
K
Strip about 1" of insulation from one L
end of each of six 4" wires. Though
the colors don’t really matter, it’s
helpful to have 3 wires in each of
2 colors. I used red and black.

Tin the stripped end of each wire
and wrap it around one of the 6 screw
terminals on the switch. Give the
wire a twist or two, tighten down the
screw, and insulate the connection
with heat-shrink tubing. One row of 3
contacts on the switch should be all
“red” and the other 3 all “black,” as
shown (Figure J).

To keep the switch from rotating,
apply 2 small pads of double-stick
foam tape to the top — one on each
side of the handle (Figure K). Peel
the backing off the tape and insert
the switch into the mounting hole
from inside the enclosure. Align it,
then press the tape into place. Slip
the label plate over the threaded shaft
and then add the panel nut. Tighten
it gently with a wrench (Figure L).

100

M 7.ADD THE POWER &
PHONO JACKS
N
Attach 4" leads to the DC power
O jack and each of the 2 phono jacks.
In each case, ground (black) goes to
TIPA small flat- the outer or “case” contact. Solder
and insulate the connections with
blade screwdriver heat-shrink tubing (Figure M).
may help with lifting
and pushing the Insert the DC power jack through
rubber to get it in the mounting hole in the top panel,
just right. from outside the enclosure, and
secure it inside with the bundled
P washer and panel nut. Tighten gently
with a 14mm wrench.
Q
Insert one of the phono jacks
through one of the mounting holes
in the side panel, from inside the
enclosure, and secure outside with
the bundled washer and panel nut.
Repeat for the other jack. Tighten
gently with a wrench (Figure N).

8.INSTALL THE MICRO
FLEX LIGHT

Remove the D-ring from the end of
the micro flex light by using a pair of
needlenose pliers “in reverse”: close
the jaws, insert the nose into the ring,
and then gently pull the handles apart
to pry the ring open. Then slide the
lapel clip fitting off the end of the lamp
body (Figure O). Discard the ring and
clip or save them for another project.

Fit the rubber grommet into the
center-top hole in the front panel. It’s
easy; just squish it in until the lip of
the hole is cleanly engaged with the
groove in the grommet (Figure P).

Insert the bottom of the flex light
into the grommet from above and
push it into the enclosure (Figure Q).
This will take a bit of force, but not
much, and will hold the light securely
in place. You can adjust its position as
needed, or remove it completely to
replace the batteries.

makezine.com 101

PROJECTS OPTICAL TREMOLO

9.WIRING AND Audio pot
ASSEMBLY Photocell
Photocell
Wire up the circuits using an 8- Rheostat
position terminal strip, as shown, Switch com –
cutting the leads to length and strip- Rheostat
ping the ends as you go (Figure R). Switch L1+/L2–
These “European-style” terminal Switch L2+/L1–
strips are nice because all you have
to do to make a connection is insert R Phono jacks +
the stripped wire end and tighten Phono jacks –
the screw. For ease of access and Audio pot
assembly, the terminal strip is not Power jack +
mounted to the enclosure, and just Phono jack –
hangs freely. By the time all 16 Switch com +
connections are made, it’s quite Motor
secure and won’t wobble around. Motor

Put the plastic bottom of the TIPThree feet
enclosure in place and secure it with
the 4 bundled screws. Then attach are less likely
adhesive feet (Figure S). to wobble on an
uneven surface
10. POWER IT UP S than 4.

To run the motor, 3V DC is supplied T TIPIf you’re
through the power jack, which takes a
size M plug. You can use a 3V wall wart U using a laser
to run the unit from mains power. V printer, you may
notice that the
You can also build a simple battery printed transparency
pack with a ready-made 2×AA battery acquires a slight
holder, a size M coaxial plug, and a bit curl from the heat.
of heat-shrink tubing. Attach it to the To flatten it, simply
outside of the enclosure with velcro flip the printed film
(Figure T). over and “print” a
blank page on the
11.MAKE THE opposite side.
SWEEP DISKS

Download the sweep disk art from
makeprojects.com/v/33 and print it
onto an 8.5"×11" transparency. If you
want to design your own disk art, an
SVG version of this file is available.

Cut out each disk using sharp
scissors. Then apply a 3"-diameter
velcro dot to the center of each disk.
Use the softer, “loop” velcro on the
sweep disks.

Apply a matching “hook” dot to the
top of the aluminum mounting hub
(Figure U).

102

Gunther Kirsch (top; oppostie, Fig. V) Slip the hub over the motor shaft. Make Going
sure the hub is high enough to clear the motor Further
screws when it rotates. Tighten the setscrew,
using the Allen wrench that came with the To take your Optical
hub, to secure it to the shaft (Figure V). Tremolo Box to the next
level, consider these
12.ROCK YOUR OPTICAL improvements to the
TREMOLO BOX basic design:

Pick your favorite sweep disk and attach it 1. Upgrade to a pulse-
to the hub by joining the velcro dots. width-modulation (PWM)
motor controller. A series
Plug your sound source into one of the rheostat is a simple, cheap
2 phono jacks, and your amplifier into the speed control, but it’s
other. The tremolo circuit is symmetrical, inefficient, and does not
so it doesn’t matter which jacks you use. perform as well at low
speeds. Here’s a good
Plug in the power supply. Turn on the flex PWM circuit based on a
light, then flip the switch in either direction. 555 timer chip: dprg.org/
Which direction the disk turns may vary the tutorials/2005-11a/
effect depending on the disk pattern.
2. If you use a PWM
The knob on the right, above the switch, controller, switch to 9V
controls the motor rotation speed. At low power (standard for FX
positions, the motor may have a hard time pedals) and upgrade the
getting started. Try turning the speed up a motor. Most 9V motors
bit and then adjusting it back down to get (e.g. RadioShack #273-
the lower speeds. 256) are higher qual-
ity than 3V motors, and
The knob on the left controls the intensity often have fully threaded
of the tremolo effect. Turn it clockwise for mounting holes.
more tremolo, counterclockwise for less. The
brightness of the light on the photoresistor 3. Add a DPDT “stomp
also affects the tremolo intensity, and though switch” (e.g. SparkFun
the high-intensity LED in the flex light provides #COM-11151) so you can
plenty, you should experiment with other light turn the effect on and
sources. Especially the sun! off with your foot.

Sean Michael Ragan is technical editor of MAKE magazine. His work has 4. Modify the box to
appeared in ReadyMade, c't – Magazin für Computertechnik, and The Wall operate using reflected
Street Journal. light, instead of transmit-
ted light, so the sweep
disks can be printed on
plain white paper.

We look forward to
seeing what mods you
come up with.

makezine.com 103

PROJECTS COUNTRY SCIENTIST

Explore your
world through
a pinhole.

By Forrest M. Mims III

Digital Pinhole A sophisticated pinhole camera Gregory Hayes; Forrest M. Mims III (pinhole shots)
Photography can be quickly made from a digital
camera with a removable lens, a
a TIME: A FEW MINUTES a COMPLEXITY: EASY camera body cap, a beverage can
(or aluminum foil), a straight pin,
Long before the digital photography era, I enjoyed mak- and some tape.
ing photographs with a 35mm film camera equipped
with a pinhole instead of a lens. The editors of Popular Fig. A: Three images of the sun
Photography magazine liked the results and published and an arrow on a computer
my article “The Pinhole: A ‘Lens’ that Just Won’t Quit.” screen, photographed through 3
pinholes mounted on a Canon 40D
Much has happened since that article was published back digital camera. The largest pinhole
in April 1974. A renaissance of sorts has occurred in pinhole (the width of a 0.6mm-wide pin)
photography, and Justin Quinnell is among its leaders. His produced the brightest but fuzziest
website pinholephotography.org is loaded with hints, tips, and images (at right). The smallest
unique pinhole images. (See makezine.com/go/quinnell for pinhole (0.3mm) produced the dim-
an inspirational video about Justin’s work). mest but sharpest images. Note:
all images except Figure C were
Suitable Cameras enhanced using Microsoft Digital
Image Pro software.
Any camera with a removable lens has potential for pinhole
photography. Conventional film cameras can be used, but digital Fig. B: Handheld beverage-can
cameras with removable lenses are ideal. The exposure time pinhole image of barbed wire
can be easily changed, and results are available instantly. A new illuminated by flash and the
entry-level digital SLR costs $500 or more, but you might find morning sun (1/60 sec., ISO 320).
a used one for considerably less.
Fig. C: Sun Spray, a handheld image
104 enhanced only by the crown burr
formed in the aluminum foil pinhole
(1/8 sec., ISO 100).

Characteristics of 1/20 sec., ISO 320 Pinhole
Pinhole Images 1/4 sec., ISO 320 Tips &
1/5 sec., ISO 320 D Samples
Pinhole images are fuzzier than those made
through a lens, but that can be an asset. If The best advice for the
the fuzz is excessive, you can sharpen your new pinhole photographer
images by using a smaller pinhole or photo is one word: experiment.
processing software. Figure A shows the Try various pinhole sizes,
sharpening that resulted from reducing the mounting methods, and
pinhole size from 0.6mm to 0.3mm. distances from your cam-
era’s sensor. Be careful
Another characteristic of pinhole cameras to keep dust off your
is nearly infinite depth of field. Make a pin- camera’s sensor when
hole photo of a very close object with a dis- removing the lens to
tant building or mountain in the background install your pinhole.
— it’s all in focus. You can even use the sun
for the distant object (Figure B), but it will As for subjects, the
be fuzzy unless the exposure is brief. world is your limit. Unlike
a camera with a lens,
Pinholes punched through foil or thin it’s easy to include the
metal leave behind a projection of torn sun in pinhole photos.
metal on the exit side known as a crown Just remember never to
burr (see makezine.com/go/astakhov). look directly at the sun
Pinhole photographers often remove the through a pinhole camera.
burr with sandpaper. When left in place, the
burr can cause uniquely beautiful effects, On the following pages
especially when making pinhole photos you will see pinhole
of the sun, as shown in Figure C. images of the sun during
the annular solar eclipse
Pinhole Exposure Times of May 20, 2012. Both
images were made simply
Pinholes admit much less light than a con- by removing the camera
ventional camera lens, so exposures must lens and holding a sheet of
be longer. This usually means the camera aluminum foil with a few
must be mounted on a tripod or placed on dozen pinholes over the
a stable surface. But thanks to the high sen- lens opening.
sitivity of digital cameras, handheld photos
are often possible when the scene is brightly Figure D shows three
illuminated. I’ve made handheld pinhole dramatically different
photos at speeds from 1/30 second (bright views of a high-voltage
sunlight) to 1/8,000 second (the sun itself). power transmission
tower, all made without
a tripod.

AB C

makezine.com 105

PROJECTS COUNTRY SCIENTIST Gunther Kirsch (step shots)

How to Make a
Foil Pinhole

The pinhole images I published
in Popular Photography and my
recent eclipse images (shown
here) were all made by pushing
an ordinary 0.6mm-diameter
pin entirely or partially through
aluminum foil. Here’s how:

1. Use scissors to cut a

square of aluminum foil large
enough to cover the lens
opening of your camera.
Heavy-duty foil is best, but
standard foil is OK.

2. Place the foil on a desk

protector, place mat, or
other flat substrate that has
a slightly resilient surface.
Smooth the foil by rubbing it
with the tip of your finger.

3. Carefully press the pin

into but not completely
through the foil. For initial
experiments, the diameter
of the hole should be about
half the diameter of the pin.

4. Remove the lens from

your camera and place the foil
over the lens opening with the
pinhole roughly centered. The
topside of the foil should face
away from the camera. Use
masking tape to secure the
foil in place. Be sure no stray
light can enter the camera;
it will wash out your images.

106

How to Make a 1. Rinse out an empty bever-
Better Pinhole
age can with water. Carefully
For optically cleaner images, cut the top and bottom off,
a pinhole formed in thin sheet cut lengthwise, and flatten to
metal is best. This method is create one metal sheet.
easiest to implement by mount-
ing the metal onto a camera 2. Use old scissors to cut
body cap that is placed over the
lens opening when the lens is several 1" squares from the
removed. Aluminum or copper flattened can.
sheet metal from a hobby store
will work, but the simplest and 3. Place a metal square on
cheapest source is an alumi-
num beverage can, pie tin, a flat wood surface.
or food tray. Put the point of a straight

Pinhole photographers pin at the center of the square
use various methods to form and hold it in place with pliers.
pinholes in sheet metal (search
Google for details). I prefer Lightly strike the head of
the “brute force” approach, as the pin with a small hammer
detailed here at right. so that the pin just pierces the
metal to form a circular hole
Experiment! about half the diameter of
the pin.
Explore the tutorials at pin
holephotography.org and other 4. Place a sheet of 220-grit Make pinholes in several metal squares
pinhole photography websites. so you can experiment with them.
After you learn the basics, sandpaper on a flat surface,
mount your pinhole camera business side up. Rub the
on a rigid tripod and try mak- backside of the metal square
ing portraits of perfectly still against the sandpaper to
friends and relatives. Make a remove the crown burr, using
time exposure of the move- circular strokes.
ment of the stars across the
night sky. Or mount a pinhole 5. Look through the pinhole
on a light-tight extension tube
to make a telephoto pinhole. to check its uniformity. About
Once you start making pinhole two-thirds of my pinholes
images, you’ll soon think of made in this fashion appear
many other ideas. perfectly circular, which is
what you want.
Forrest M. Mims III (forrestmims.org), an
amateur scientist and Rolex Award winner, 6. Bore a ¼" hole in the cen- A magnifier such as a 10x loupe is very
was named by Discover magazine as one of helpful.
the “50 Best Brains in Science.” His books ter of the camera’s body cap.
have sold more than 7 million copies.
7. Place a metal square with

a pinhole over or behind the
body cap so the pinhole is
centered in the ¼" aperture.

Secure it tightly with
removable masking tape so
you can try other pinholes
later. When you find the best
one, secure it with adhesive. a

makezine.com 107

PROJECTS SCRATCH-A-TREAT Has your cat left scratch marks
on everything from grandmoth-
a TIME: A WEEKEND a COMPLEXITY: MODERATE er’s kneecaps to your grandfather
clock? It’s time to train Kitty to
Cat use this scratching post instead
Scratch of everything else in your home.
Feeder
A catnip cup in the top will
attract your cat and place her in
natural scratching position. Each
time the cat claws downward on
the spring-loaded carpeted cylin-
der, this device will deliver up to
4 special treats. Because you con-
trol the number of treats, you can
keep your cat lean and gradually
wean her off the treats altogeth-
er as she becomes accustomed to
using the post, if you wish.

A catnip cup A attracts the cat
to pull down on a carpeted scratch
cylinder B causing the inner tube
C to press down on a plunger D
and also causing the wedges E
to engage rotation pegs.

Pegs rotate a treat turntable F
which releases treats through a
hole in the treat disk G whence
they fall onto a base tray H to
reward the cat.

A spring I attached to a retainer
J in the support tube K pulls
the plunger back up, raising the
scratch cylinder to the starting
position. The spring rebound is
limited by the strap L .

Build a snack-dispensing scratching post that
will make Kitty forget the couch and curtains.

Written and photographed by Phil Bowie and Larry Cotton

108

A

C

J

I
K
B

D E
F
G
L Timmy Kucynda

H
makezine.com 109

PROJECTS SCRATCH-A-TREAT

Dowel, Extension spring
0.44"×10.25 "×0.040 ",
acrylic working load 1.4lb
such as Hillman #222,
Berber Dowel, wood ¼" diameter, from Lowe’s. You’ll
carpet scrap
15"×16" 6" length cut it to 5¼", so shorter

¼" diameter, versions will work if you

2" length can find them.

Softwood
lumber 2×4
Aluminum flat bar
nominal, 12"

⅛"×½"×2" long length actually

measures 1½"×3½"

Materials
& Tools

Fabric strap PVC pipe PVC pipe PVC pipe Schedule 40,
non-stretching, sewer & Schedule 40, 1" nominal, 1.315" OD,
¾" or 1" wide, drain type, 3" nominal, 0.133" wall thickness,
5¼" length 4" nominal, 3½" OD, 15" length The outer
0.08" wall 0.216" wall
thickness, thickness, diameter is almost exactly
18" length 12" length 17", the wall thickness
between 1" and T".
For a table of typical PVC
dimensions see makezine.
com/go/pvcdims.

PVC pipe Schedule 40,
1¼" nominal, 1.660"
OD, 0.140" wall thick-
ness, 18" length This

is approximately 13" OD,
12" ID, T" wall thickness.

» Softwood shelving board, as Dritz, available as a kit » Hammer, small Gunther Kirsch
¾"×11½"×18" » Various screws and brads » Pliers: needlenose and
» Table saw You can do this
» Softwood strip, ¼"×1"×50" side cutting
» Softwood or plywood, project with hand tools, but » Metal-cutting shears
power tools will be more » Screwdrivers
½"×4"×6" for top disk accurate and save time. » Files
» Screw eye, small » Band saw » Square, small
» HDPE (high-density polyeth- » Center punch » Hot glue gun
» Drill press » Glues: wood glue, hot glue,
ylene) sheet, 2mm We found » Handheld drill
90mm disks on eBay that » Drill bits including spade bits cyanoacrylate glue (aka super
were perfect. You could also and an adjustable (fly cutter) bit glue), and spray adhesive
use furniture sliders or similar » Power sander and sandpaper » Scrap wood for V-block and
plastic material. other drilling/sawing jigs
» Fabric snaps, 3" OD (2) such

110

1a Base & edging 1b Support tube holder 2a Support tube

EDGE: 2×4 wood
1"×¼"
wood strips

BASE: 1¾"
11"×11"×¾" 1"

plywood or 15¼"
wood shelving
Section Hole: Drill using
NOTE Keep your adjustable 13" fly cutter bit
22" square
bit set at 1⅝" diameter for drilling
other parts later. 3½" square

PVC tubing 13" OD, T" wall

1d

1.MAKE a press fit between the holder to the center of any face of
THE BASE and the support tube. the holder with a wood screw.

1a. Cut the base square, Chamfer the holder’s edges 2.MAKE THE
mitering ¼" wood strips so on a table saw or band saw. SUPPORT TUBE
they form a lip all around COMPONENTS
to help retain the dispensed 1c. Fasten the support tube
treats. Fasten with brads holder to the center of the 2a. Cut the support tube
and a bit of wood glue. base with wood screws. from 1¼" PVC pipe, using
a table saw, following the
1b. Follow the support tube 1d. Insert a stub of 1¼" PVC diagram. To cut the slot in
holder diagram to build the pipe (13"-OD) into the hole the center of one end, hold
holder. For safety, drill the as a mask, then sand, prime, the pipe vertically and use
hole with a fly cutter before and paint the base a light wooden pushers at the
cutting the wood to size. The color so the cat treats will bottom and side as shown
hole is nominally 13", but drill show up on it. (ask a friend to help).
it slightly undersize to ensure
Attach a male fabric snap

makezine.com 111

PROJECTS SCRATCH-A-TREAT

2b Plunger 1" 2e Split ring

Small screw-eye Make 3 from 1¼" PVC.

1"×¾" ¾" 2"
wood plug ¾"
5"- 1"
1" PVC tubing
17" OD

2c Top spring retainer Notch one ring near split,
Make from "-wide aluminum. approx. half material
thickness deep.
14"
"×" cutout 6"
on each end

Drill 5" hole on centerline, 1" from bottom.

2d Spring

5"

2b. Make the plunger from corners before cutting the 2e. Make 3 split rings from
1" PVC pipe, following the part to final size. 1¼" PVC pipe per the split
plunger diagram. Cut the ring diagram.
1"-diameter wood disk on a 2d. Cut the extension spring
band saw, sand it to fit tightly down to 5¼" over the closed Note that one has a notch
in the ring, and glue it in place. coils, per the spring diagram. in its outside surface near
Sand the top and bottom of Use needlenose pliers to the split, which can be rough-
the plunger flat and square, bend out new hook coils on cut with a band saw, and the
then insert a small screw eye the ends, then cut them with inside corners filed square.
in the center of one face. side-cutting pliers. Insert the
hook coils into the top spring Put the top spring retainer
2c. Make the top spring retainer and the plunger in place. Then, expand one of
retainer from the aluminum screw eye. Then insert that the rings without the notch
bar, following the diagram, assembly into the support (it’s not easy) and push it over
using a band saw. For safety, tube per the assembly dia- the top end of the support
drill the hole and notch the gram in step 4 on page 114. tube to hold the top spring
retainer in place.

112

Turntable & rotation pegs (shown at ¾ scale) IMPORTANTCenter-punch

Use the full-sized turntable template provided at all hole locations before drilling.
makeprojects.com/v/33. Peg specs are in red.
3b
Wood: 3" OD, ¾" thick
45˚ PVC: 3" ID, ¼" wall

22.5˚

45˚

1.28"
or use
template

Side View 3"
2" ¾"-thick wood

3c
3d

Eight ¼" holes, ¼" deep 3½"

The turntable is just ¾" deep, but start with at least
3a a 12" length of pipe for safe cutting on a power saw.

3.MAKE THE TREAT critical. The red lines indicate set to stop at a depth of ¼",
TURNTABLE peg locations; extend them drill the 8 peg holes.
onto the sides of the PVC
3a. Follow the diagram to pipe. Draw a line around the 3d. Cut eight ½" rotation
make the turntable and rota- outside, centered between pegs from ¼" acrylic dowel,
tion pegs. When cutting the the 2 faces. ensuring the ends are square
¾" wood and 3" PVC pipe, and smooth. Tap them lightly
ensure that the cuts are 3c. Drill the center hole with a into the peg holes with a ham-
straight, parallel, and square fly cutter bit. This hole should mer and glue them in place.
to the sides. The wood disk initially fit snugly over the The ends of the pegs should
should fit tightly into the PVC support tube. Drill the 8 treat just clear the ID of the 4" PVC
ring. Glue it in place and sand holes using a spade bit. drain pipe.
both faces smooth.
Make a drill press jig for the You can radius the ends
3b. The positioning of the peg holes. Using a length of slightly on a sander to help
rotation pegs and the loca- the 1¼" pipe (13" OD) resting achieve a close fit.
tions of the treat holes are in a wood V-block, with the bit

makezine.com 113

PROJECTS SCRATCH-A-TREAT

3f Treat disk & bearing washer 4a

3½"

1.28" "
13"

13" 2"
Tab: 6"
1"

4 Split ring
Split ring (before expanding)
(before expanding) Bearing washer

These Top spring These Turntable
parts fit retainer parts fit
inside Spring Treat disk
support over
Plunger support Notched split ring
tube (before expanding)
Support tube
Snap in tube
center
of face Support
tube
holder

3e. After the turntable is com- Then cut out all the parts 4a. Press the notched split
pleted, sand the large center with shears. ring on last, so that the bent-
hole so it rotates freely on the down tab on the treat disk will
support tube. Use side-cutting pliers to be trapped by the notch to
snip the tab on the inside keep it from turning.
3f. Cut the treat disk and diameter of the treat disk, and
bearing washer from 2mm carefully bend it down 90°. Position the bottom surface
HPDE plastic, following the of the treat disk 5½" from the
diagram. (If you bought 4.ASSEMBLE THE bottom of the support tube.
90mm disks, they’re almost SUPPORT TUBE.
exactly the size of the treat 4b. Press the support tube
disk.) Lay out the 2 parts on Following the assembly dia- assembly into its holder on
the plastic and drill both large gram, spread and slip the the base without fastening
holes with the fly cutter bit. second notchless split ring it. Don’t fasten the split rings
Use a ¾" spade bit for the onto the support tube from either, to allow for adjustment.
smaller hole in the treat disk. the bottom. Follow with the
bearing washer, the turntable,
and the treat disk.

114

5a Scratch cylinder 5c Top disk 17"

¼" Drill & countersink ½"
three R" holes
16" 4" OD
120˚ apart (start Make from ½"-thick wood.
1¼"
½" anywhere on
circumference).
4" PVC
Hot-glue wedges
in place on the
back wall using
template.

Drill the R" strap
attachment hole
(anywhere on
circumference).

5b

5.MAKE THE of 4" PVC pipe. Temporarily them accurately.
SCRATCH spray-glue the template to the
CYLINDER PARTS inside of one of the pieces, 5c. Using a band saw, make
and cut 2 sets of wedges with the top disk and sand it to fit
5a. Cut the scratch cylinder, a band saw. Super-glue the tightly into the top end of the
following the diagram. duplicate wedges together, scratch cylinder. Use the fly
doubling their thickness. cutter bit (reset to just under
5b. Cut the 2 sets of wedges 17") to drill its center hole.
using the full-sized template On another copy of the tem-
at makeprojects.com/v/33. plate, cut out the wedge holes. Fasten the top disk to the
These will rotate the turn- Temporarily spray-glue this cylinder using 3 small flat-
table one-half position on template to the inside wall of head wood screws.
the downward stroke of the the scratch cylinder 1¼" from
scratch cylinder, and then the bottom end, anywhere on 5d. Wrap the scratch cylinder
one-half position on the the circumference. Hot-glue with Berber carpet hot-glued
upstroke, releasing the treat. the wedges in place, using the in place.
negative template to position
Split lengthwise an 8" piece

makezine.com 115

PROJECTS SCRATCH-A-TREAT

6a Inner tube 6b

Make from 1" PVC ½" Nail holds
½" tube against
Drill holes straight
through both sides. fence

Tube holder

Cut slot 1" wide and 1"
file to freely clear the
94"
top spring retainer.

13¼"

NOTE: Tube looks widen Jig
identical from to 2" screw
both sides.
30˚ 3"

30˚

¾"
or less

7a Catnip disk, and disk pin

17"

Cut 1" diameter

from 5" or 1"

6c 1" plastic. " wood dowel

6.MAKE THE 6c. On both sides of the tube, 7b. Insert the catnip disk pin
INNER TUBE widen 3" of the slot to 2" with through the end of the inner
a band saw as shown. Use a tube, and glue the catnip disk
6a. Following the diagram, wood wedge to hold the slot into place using the pin as
drill the ¼" holes in the 1" PVC apart for easier blade access. a stop and gluing surface.
pipe (17" OD). Then make File the slot if necessary to
a wood jig and screw the pipe make sure it clears the top 7c. Press and glue the inner
to it through the holes. spring retainer during the tube into the cylinder top disk.
plunge stroke. It must be centered within the
6b. On a table saw, cut the scratch cylinder.
top slot 1" wide. Allow for the 7.ASSEMBLE THE
radius of the blade and the SCRATCH CYLINDER
thickness of the jig itself to
determine where to stop cut- 7a. Follow the diagram above
ting. Finish extending the top to make the catnip disk and
slot on a band saw to its full disk pin.
94" length.

116

8.TEST AND Tame
TROUBLESHOOT That Kitty

Load the turntable with treats, and drop the When you first set up your Scratch-a-
scratch cylinder assembly over the support Treat, use the strap’s end snap to limit
tube assembly. The inner tube must slide the spring’s bounce when Kitty releases
easily into the support tube. the scratch cylinder. Use the shorter snap
position to disable the plunge action alto-
Pull down on the scratch cylinder to cycle gether when Kitty becomes accustomed
your Scratch-a-Treat, testing for smooth oper- to using Scratch-a-Treat as a proper
ation and ensuring that treats are dispensed. scratching post.

If you feel friction, there could be several You don’t need to remove the scratch
sources: cylinder to load treats. Simply unsnap the
» Between the slot in the inner tube and the strap, lift the scratch cylinder about 4",
rotate it clockwise, and let go. Load the
top spring retainer. Try removing the scratch treats into the turntable, then reverse the
cylinder, turning it 180°, and replacing it. Or process to drop the scratch cylinder back
widen the slot slightly, especially at the top. into scratching position.
» Between the inner tube and support tube.
Remember that the inner tube must be A variety of treats can be used. We
centered in the scratch cylinder. favor the crunchy, catnip-flavored
» Between the turntable and support tube. Temptations brand.
Sand the center turntable hole as necessary.
» Between the rotation pegs and the wedges Rubbing a bit of catnip onto the carpet
inside the scratch cylinder. Smooth these will help attract your cat initially and
parts as necessary to reduce friction. encourage scratching.
If treats aren’t dispensed, adjust the
height of the turntable on the support tube As with all pet training, praise Kitty
and/or turn the treat disk (and its split ring) generously when she uses the Scratch-
so it releases all the treats reliably. a-Treat, and administer a stern scolding
when she does not.
½" 2"
Grandma’s knees will be happy.
3" fabric snaps
Larry Cotton is a semi-retired power-tool designer and part-
Cut 5¼" from ¾"–1" wide strap. time community college math instructor. He loves music and
musical instruments, computers, birds, electronics, furniture
9 Strap design, and his wife — not necessarily in that order.

9. FINAL Phil Bowie is a lifelong freelance magazine writer with three
ASSEMBLY suspense novels in print. He’s on the web at philbowie.com.

Remove the scratch cylinder and fasten the 2 makezine.com 117
lower split rings to the support tube with short
screws. These must not protrude inside the
support tube.

Make the fabric strap per the strap diagram
and screw it to the inside bottom wall of the
scratch cylinder. Turn the support tube in its
holder to align the snaps. a

TEST BUILDER: Isabella Ghirann, MAKE Labs

PROJECTS WII NUNCHUK MOUSE Gregory Hayes

Wii Nunchuk
Mouse

Bring console-style motion
control to your PC.

By Gabriel Bianconi

118

a TIME: 1 HOUR a COMPLEXITY: EASY MATERIALS

Today, more and more devices are using motion » Nintendo Wii Nunchuk
control. From tablets to cellphones to game consoles, con-troller $17; third-party
people are getting used to interacting with electronics controllers may not work.
using gestures. Personal computers, however, have
lagged behind a bit. Unable to find a suitable gestural » Arduino Uno microcontroller
controller for my Windows PC on the consumer item #MKSP11 from Maker Shed
(makershed.com), $35

» 140mm male/male jumper
wires (4) item #MKSEEED3
from Maker Shed, $9/65

market, I set out to build my own. TOOLS
I based my design on the Wii Nunchuk controller

for several reasons. First, it’s a versatile, comfortable, » Windows PC Mac/Linux
well-designed controller; second, it‘s cheap and easy users will have to adapt the
to find; and third, its native I2C serial protocol is easy Python script.

to interface with Arduino. As a bonus, the connector

will accept standard jumper wires, so there’s no need

to cut up the cable or use a dedicated adapter.

The Arduino runs a sketch that reads data from

the controller and prints to the computer’s serial port.

The computer runs a Python script, which receives

serial data and emulates a mouse.

1. Install the 1c. Download Python 2.7.2 for 1e. Download pywin32 at
Windows at python.org/ftp/ makezine.com/go/pywin32
software. python/2.7.2/python-2.7.2.msi and run the installer.
and run the installer. You can
1a. Download the Arduino IDE find IDLE, the Python IDE, at 2. Connect the con-
for Windows at arduino.cc/ Start → Python 2.7 or launch
en/Main/Software. Extract it at C:\Python27\Lib\idlelib\ troller to the Arduino.
the arduino-1.0 folder to your idle.pyw.
hard drive. Inside this folder 2a. We’ll use 4 colors of
you’ll find arduino.exe. NOTEYou should not download jumper wires to simplify
the instructions. Insert the
1b. Download the Python 3. The script used in this project jumpers into the Wii Nun-
ArduinoNunchuk library at won’t work with this version. chuk’s connector as shown
github.com/GabrielBianconi/ in Figure A, page 120.
ArduinoNunchuk. Extract
the ArduinoNunchuk folder 1d. Download the pyserial 2b. On your Arduino, connect
to your hard drive. Open the module at pypi.python.org/ the red wire to +3.3V and the
Arduino IDE and select File → pypi/pyserial. Extract the black wire to GND. Connect
Preferences. Note the folder pyserial-2.6 folder to C:\. the green wire to A5 and the
under Sketchbook folder and Launch the command prompt yellow wire to A4 (Figure B).
open it in Windows Explorer. window at Start → Accessories
Look for a folder named → Command Prompt. Type 3. Upload the
libraries. If there isn’t one, cd /d c:\pyserial-2.6
you should create it. Move and hit enter. Now type c:\ Arduino sketch.
the ArduinoNunchuk folder Python27\python setup.py
into libraries. install and hit enter again. 3a. Connect your Arduino
to your computer via USB.
If this is the first time, you’ll

makezine.com 119

PROJECTS WII NUNCHUK MOUSE

need to install the required ANALOG GND RESOURCES
driver. Windows will not be IN A5
able to install it automatically, ANALOG » Python 2.7.2
so you’ll need to select it in POWER IN A4 python.org
arduino-1.0/drivers. 3.3V
» Pyserial module
3b. Open the Windows A pypi.python.org/pypi/
Control Panel and search for pyserial
the Device Manager. You can
find the port in which your » Pywin32 extension
Arduino is inserted under makezine.com/go/
Ports (COM & LPT). Open the pywin32
Arduino IDE and select the
correct port under Tools → » Arduino IDE arduino.
Serial Port. cc/en/Main/Software

3c. Relaunch Arduino. Select » ArduinoNunchuk
your Arduino model under Library github.com/
Tools → Board. GabrielBianconi/
ArduinoNunchuk
3d. The ArduinoNunchuk
library that you’ve installed » “ArduinoNunchuk —
has an example sketch that Wii Nunchuk library for
prints the data from the Wii Arduino” gabriel
Nunchuk to the computer’s bianconi.com/projects/
serial port. Open the exam- arduinonunchuk/
ple file by selecting File →
Examples → ArduinoNunchuk » “How to hook up a Wii
→ ArduinoNunchukDemo. Nunchuk to an Arduino
Upload this sketch to your Mega” gabrielbianconi.
Arduino. com/blog/how-to-
hook-up-wii-nunchuk-
3e. Open the Serial Monitor. arduino-mega/
At the bottom right, change
9600 baud to 19200 baud B 4b. Open it with IDLE (Right- Gunther Kirsch
and wait a few seconds. You click → Edit with IDLE). Look
should see 7 columns of TIPS Ifyou can’t find the for the line which says port
values that change if you = ‘arduino_port’ and write
move the Wii Nunchuk, move example sketch, try relaunching the the correct port (leave the
the analog stick, or press a IDE. If this doesn’t fix the problem, quotes). It should look like
button. If it’s working correct- you probably didn’t install the port = ‘COM10’ (use the
ly, close the serial monitor. library correctly. same port as set up in the
Arduino IDE). Save the script
4. Set up the script. If you don’t see the numbers, you (File → Save or Ctrl+S).
probably did something wrong or
4a. Download the Python skipped a step. Make sure that the 4c. Press F5 to run the file
script at makezine.com/ wires are connected properly and and wait a few seconds. Enjoy
go/nunchuk. the baud rate and serial port are using the Wii Nunchuk as
set up correctly. a computer mouse! a

If you get an error when trying to Gabriel Bianconi is a high school student in
run the file, make sure that the São Paulo, Brazil. He is interested in technology,
port was correctly set up and both especially programming, and wants to study
pyserial and pywin32 installed. If computer science in college.
this doesn’t solve the problem, try
restarting IDLE and your Arduino.
If it still doesn’t work, restart your
computer.

120

Omnidirectional
Spray Bottle

By Jason Poel Smith Illustrations by Julie West

MODIFY A SPRAY BOTTLE SO IT WORKS YOU WILL NEED: Spray bottle, 16oz or
WHEN HELD AT ANY ANGLE. If you replace
the hard suction tube with flexible tubing and bigger » Flexible tubing, ⅛" ID, ¼" OD, such
a weight on the end, the tubing will naturally as aquarium air line » Stainless steel nuts,
fall to the lowest point of the container. ¼" (5) » Scissors » Glue (optional)

1. Cut the tubes to length. NOTE: Even stainless steel
eventually corrodes. After
Cut the original spray bottle tube, leaving each use, remove the sprayer
about 1" sticking out past the screw cap. assembly to dry.
Then cut the flex tubing about 1" longer
than the cut portion of the original tube.

2. Attach the 2 cut tubes.

The suction tube on a typical spray bottle
has an outer diameter between ⅛" and ¼",
so the flex tubing should make a good seal
without any adhesive. Slide it onto the origi-

»nal tube until you get a firm seal, with at

least ¼" of overlap. If you don't get a satis-
factory seal, use glue. With both tubes clean
and dry, apply a thin layer of glue around the
lower ½" of the original tube. Slide the flex
tubing onto the original tube, overlapping by
at least ½", and slowly twist the flex tube to
help spread the glue evenly. Let the adhesive
completely cure before continuing.

3. Add the weight.

Twist a nut onto the end of the flex tubing
and turn the sprayer upside down to see
how low the tube hangs. Add nuts until the
tube hangs almost down to the cap. The
stiffer the tubing, the more nuts you’ll need.
I used 5.

USE IT

Fill the bottle with liquid and enjoy spraying
up, down, and upside down! If the tube gets
stuck, give the bottle a gentle shake. a

Jason Poel Smith is a helicopter tooling engineer. When he’s not inventing,
he’s spending time with his amazing family.

makezine.com 121

PROJECTS BREWING SAKE

Kanpai!

a TIME: 2–5 WEEKS a COMPLEXITY: MODERATE

Brew sake The bottles are slender and elegant and

at home. colored a frosty white or baby blue, alcohol

By Alastair Bland levels usually hover in the mid-teens, and
the price tags often exceed 30 or 40 bucks.

For these reasons, sake has gained a reputation among many Gregory Hayes

Westerners as the Eastern equivalent of fine wine — something

rare and precious, to be consumed in tiny portions, and more

often than not simply out of reach.

122

Gunther Kirsch But this favored table beverage of Japan is actually a MATERIALS
simple grain-based brew, much like beer. And while it’s
true that good sake, often called “rice wine,” is expensive, For 1 gallon of sake:
there’s an easy way around the price tag: make it at » Short-grain rice, white, 3.3lbs
home. It takes just 4 ingredients, and anyone, using only » Cold Mountain koji, 20oz tub
the most basic of beer-making equipment, can trans-
form a sack of pearly white rice into fragrant, perfumey Check your local Japantown
sake in as little as 12 to 15 days. (I got mine from Nijiya Market in
San Francisco), or order online
Born in China some 4,000 years ago as rice cultiva- from Pacific Mercantile (pacific
tion took root, sake culture found its way to Japan about eastwest.com) and select the
2,000 years later, where it bloomed into a refined and quickest shipping since it needs
hallowed tradition. Over time, rice varieties would be to be kept cool.
bred specifically for use in brewing, and today those who » Yeast, champagne or dry white
make sake — often in tiny microbreweries with their own wine variety, 1g
proprietary yeasts and rice strains — are esteemed as » Water, 4qt
among the greatest of craftsmen.
TOOLS
Brewing sake requires rice, water, yeast, and, finally,
one more essential component: a mold native to East Specialty brewing items are
Asia called Aspergillus oryzae. We have this critter to available at most homebrewing
thank for black bean sauce, soy sauce, miso, and other and winemaking supply stores.
cultured food products of Asia. A. oryzae releases an » Brewing bucket, 5gal typically
enzyme that breaks down complex carbohydrates into
simple sugar. Since sugar is what yeast turns into etha- 12" OD × 17½" tall
nol, the first step in making sake is to convert steamed » Airlock and rubber stopper
rice into a sticky, sweet porridge.
adds about 5" to bucket height
Purists may wish to start from scratch by buying » Mini-fridge (optional) to fit
spores of the A. oryzae mold and sprinkling it over a
batch of steamed rice. Here, the mold blooms and does your bucket and airlock, with a
its magic: the grain turns as sweet as candy. The rice is temperature range that goes up
now called malt-rice, or koji, and can be dried or frozen to 55°F–65°F. We used a Vissani
and stored for months until needed for brewing. 52-Bottle Wine Cooler, Home Depot
item #MVWC52B (homedepot.com).
If weather permits, omit the fridge
and leave your brewing bucket in a
cool garage or basement where the
temperature is a steady 55°F–65°F.
» Measuring cup
» Scale for measuring rice, yeast
» Colander, stainless steel
» Large pot for steaming the rice
» Cotton towels
» Funnel
» Ladle
» Glass jug, 1gal for secondary
fermentation
» Sanitizing agents One Step
No Rinse Cleanser or iodine
» Rubber tube for siphoning
» Beer bottles
» Bottle caps
» Hand-operated bottle capper
» Siphoning pump (optional)
» Bottling valve (optional)

makezine.com 123

PROJECTS BREWING SAKE

A

C

B 1. Wash, soak, and steam.

Most sake homebrewers opt to purchase Rinse the rice with cold water through a colan-
dried, premade koji ready to use. A favored der until the water drains out clear (Figure A).
product is that of Cold Mountain, which sells
20oz plastic containers full of dried rice inocu- Soak the rice for 90 minutes. Fully wrap the
lated with A. oryzae. rice in a clean cotton towel (Figure B), then
place it in a colander within a large pot. Add
You’ll also need yeast, and many beer and about ½" of water and simmer over low heat,
wine yeasts do just fine. In advanced sake making sure the lid closes tightly and the pot
brewing, the water and its particular mineral doesn’t dry out and burn. Cook the rice for
content are a matter of concern, but begin- 1 hour or more, adding water as needed.
ners can use clean tap water.
When finished, properly steam-cooked rice
Finally, there’s the rice. Brown rice is com- will be sticky and a bit rubbery between the
monly advised against, since the outer layers teeth — and palatable. If it's still al dente, keep
of each unhusked kernel contain proteins steaming it.
and fats that can, by some opinions, produce
off-flavors. Commercial brewers use specially 2. Sanitize.
bred sake rice varieties, but these are expen-
sive. Fortunately, table rice can make very Sterilize your brewing bucket, lid, measuring
respectable sake. cup, rubber stopper, airlock, and your hands
with either iodine or One Step No Rinse
The magic moment of brewing arrives when Cleanser. If using One Step, make a solution
the lid of the bucket is removed. Here, where of 1 tablespoon per gallon of water according
2 weeks before was a slurry of rice, fungi, and to the instructions, throw in everything above,
warm water, is now a naturally transformed slosh water over all the equipment, making
beverage. If all went well, the aromas should sure everything is covered, and remove it all
be beautiful — stone fruits and guava and after 2 minutes.
flower petals — and to think that they all
came from polished white pearls of rice can Cap the bucket with the lid and airlock,
be astounding. To see firsthand that sake and shake the bucket to coat the insides with
can easily be produced in a bucket in one’s the solution. Dump the solution out after 2
kitchen is just as thrilling. Here’s how. minutes. Sloshing some boiling water in the
brewing vessel afterward can’t hurt.

3. Mix.

Combine the 4qt of cold water, steamed rice,
20oz of koji, and gram of yeast in the brewing
bucket. Secure the lid (Figure C).

124

DE

G

F NOTEAny H

4. Ferment. material or surface
(hands included)
The starch-to-sugar conversion and fermen- that may come
tation will begin at once and simultaneously. into contact with
If you’ve plugged your brewing bucket with an the sake should be
airlock (Figure D), bubbling will start within considered poten-
hours, and the glugs will come increasingly tially “infected.”
rapidly. Put the bucket in a cool place to keep Sterilize everything
the sake at 55°F–65°F. thoroughly just
before use.
The fermentation, and the pace of the
glugging, will probably peak between day The sake will be relatively clear and can be
3 and day 7. When it slows to one glug every carefully (don’t stir up those funky sediments
15 minutes or so, after about 2 weeks, the at the bottom!) poured or ladled through
sake is mostly finished. a cotton cloth into a carafe (Figure E) for
immediate consumption in case you’re thirsty.
5. Sample.
Squeeze out the sake from the rice by
Open the lid and you should see the rice float- twisting the cloth (Figure F).
ing on top and yeast settled to the bottom.
6. Ferment some more.

Secondary fermentation is an important
step that clears up your sake and allows
bad-tasting esters to settle out. First, the sake
remaining among the soupy bottom dregs
must be separated from the foul-tasting yeast
sediment. To do so, pour or siphon the boozy
muck, again filtering out the rice, into a sani-
tized glass gallon jug (Figures G and H). This

makezine.com 125

PROJECTS BREWING SAKE

I

TIPWrap a cloth How to Serve Sake Gregory Hayes (serving)

around the tip of the At last, the night will arrive when your home-
siphoning pump to brewed sake comes to the table. Reverence
keep rice from clog- and respect must be shown, but don’t overdo
J ging it (Figure J). it. For one thing, you don’t need to “pair” it
with sushi. While sake and sushi are often
is your secondary fermenter (Figure I). seen hand in hand, that’s only by convention
Here, the last kicks of fermentation will and tradition — like two villagers married in
an arranged ceremony, never knowing that
peter out as the sediments precipitate to the their true soul-mates were living somewhere
bottom. This may take several weeks, with the far away. So cook whatever you want — Indian
jug kept at about 55°F. (Some brewers just put curry, Greek dolmatas, Mexican tacos, French
it right into their near-freezing kitchen fridge.) cheeses. Sake likes them all.

7. Bottle. Secondly, you can serve your sake from
square cedar cups — or just keep it real and use
When the sake is clear, with a thick layer the stemware in your cupboard. In fact, you
of sediment on the bottom, siphon it into want a glass that’s wide enough to swirl, set-
sanitized beer bottles. (A bottling valve, ting aloft those lovely aromas.
which only flows when pressed to the bottom
of the bottle, makes it easier.) Finally, for Pete’s sake, don’t drink your
sake warm or hot. This has long been a trick
Seal the bottles with sanitized caps using for masking off-flavors in lower-quality sake
the hand-operated capper. Drink within weeks — and your homebrew is anything but.
or months.
When it hits 140°F, consider the drink sterilized.
8. Age (optional). Now cap the bottles and stash them away.

If you wish to age your sake, you should You might even age some for years. a
pasteurize it prior to bottling by placing the
filled-but-not-yet-capped bottles into a pot Alastair Bland is a freelance writer based in San Francisco. He writes
of boiling water. Using a clean thermometer, frequently of food, science, and the environment. He travels frequently —
monitor the rising temperature of the sake. often by bicycle — and his journeys can be followed at his blog “Off the
Road” (blogs.smithsonianmag.com/adventure).

126

Solar Make the event
Powered memorable
Roasting with a DIY wood-
Spit fired rotisserie.

By Saul Griffith

Author Saul (left) and his friend Dan
(right) assemble the drive mechanism
from a bicycle wheel, a windshield
wiper motor, and a loop of kite string.

a TIME: A WEEKEND a COMPLEXITY: MODERATE

Courtesy Saul Griffith Not only do I enjoy making things, I also love making food, so any
opportunity that combines both is hard to pass up. Friends of mine
were getting married, and being the beautiful and unusual people
they are, planned a potluck wedding. I decided to do what I’d been
hoping to do for years: cook an entire animal on a spit. My wife and
I had a small lamb and pig both spit-roasted at our wedding and it
was a culinary highlight. How hard could it be to do myself?

makezine.com 127

PROJECTS MAKING TROUBLE

A FEW FRIENDS VOLUNTEERED TO HELP as the butcher, having just completed salting
(thanks Pete Lynn, Dan Benoit, Joe Brock, and preparing “the beast,” brought it out slung
and infinitely Mose O’Griffin). At the local over his shoulder. I think everyone in the shop
farmer’s market I met the lovely people from came to me with some comment or story of
Fatted Calf, a San Francisco charcuterie. They shared excitement, jealousy, or encourage-
were delighted to supply me with a lamb, and ment. I knew at this point that despite having
also recommended a great book, The River no idea what I was doing, this particular cook-
Cottage Meat Book, that included directions ing experience was the type of making that
for making a spit and cooking on it. brings communities and people together in
a social experience.
It was the Thursday evening before the
wedding when I went to pick up the lamb. The That evening we elected to build the rotis-
store was full of people buying sausage or serie spit that I thought would be the simplest,
some prosciutto. The store went dead quiet most easily transported, and easiest to store.

128

MATERIALS 7 A.M. Wedding day — cells through an inverter to
produce 12V. There are prob-
» Sheet metal for the fire pans and I get up, but have my 3-year- lems with both the inverter
drippings trough. We used a 4'×8' sheet old son and 3-month-old and the drive mechanism.
of 16-gauge mild steel. puppy to look after. (My wife
is baking the wedding cake.) 10:05 Our friction drive
» Metal rods or pipes (3) to hold the pans
and trough together 9:00 I’m now worried; made of a BMX bike peg
against the bike tire doesn’t
» Adjustable sawhorses (2) to support the I haven’t made progress on work well, and doesn’t give
rotisserie, height-adjustable for temperature anything, and from reading us enough gear reduction.
control (good idea, Dan) the book I’m estimating a 6- The motor moves about
or 7-hour cooking time with 100rpm, and the friction
» Steel pipe, Schedule 40, 1½" a 5 p.m. eating target. Mose drive is only about 20:1.
diameter, 10' length for the spit arrives. Sigh of relief.
10:20 Switch to using
» Baling wire to hold the roast on 9:05 We get the fire
» Windshield wiper motor, high torque, the battery of a 1959 dune
started in the 2 fire pans. buggy. This turns out to be a
low speed to drive the spit We have enough old euca- bad idea but is awfully fun.
» Solar panel to power the rotisserie lyptus logs to cook a bunch
of animals, even though it 10:30 Back to solar
(thanks, Fenix International) does consume a surprising
» Bicycle wheel to gear down the amount of wood. panels, and with the arrival
of Joe Brock we have a new
rotisserie speed 9:15 Start preparing the idea: a capstan drive. Itworks
» Steel pipe flange fitting perfectly. Fortunately I have
» Scrap of wood or metal to adapt the animal itself; we decide to brought a splicing tool and
figure out how to spin the some old kite string that
flange to your bike wheel animal once it’s on the spit. makes an excellent belt. We
» Eye bolts (2) longer than pipe diameter just wrap a few turns of the
» Various wood screws, nails, kite string, etc. 9:20 Read hilarious sec- string around the motor axle.

BUILD IT tion of River Cottage Meat 10:40 Everything now
Book: “Let’s not be delicate
1. Cut the sheet metal into three here, the pole goes in the appears to be working. The
a**hole and out the mouth.” lamb is moving at 2–3rpm
8'-long pieces: two 18"-wide for the Learned that there is indeed and the only thing to do now
fire pans, and one 12"-wide for the nothing delicate about cook- is tend the fire. And baste
drippings trough. Cut holes to thread ing a whole animal. the animal. And drink.
the pipe through.
9:25 We use too much 4:40 P.M. Still basting
2. Cut the metal pipes to size and
baling wire and my hands and drinking, but it’s now
assemble the 3 troughs. Bend the are bleeding, but the lamb time to go watch our friends
drippings trough deeply and the fire is tied to the pole. All I did get married. Quickly check
pans shallowly. to prepare the pipe was drill the temperature with a meat
some holes for pushing wire thermometer: 140°F deep
3. Bolt the eye bolts to the top of through. You should think a in the thigh. Perfect.
lot more about how to keep
the sawhorses. the lamb from rolling around. 5:10 They’re married!
Systems with orthogonal
4. Drill and tap the flange to match spikes seem very popular. I’m ready to carve. So is
Mose. People line up, and
the hole spacing of the disc brake tabs 9:45 Lamb goes onto the it’s done. I can’t believe
on the bike hub. 75 pounds of animal can
spit above the coals. We’re disappear so quickly.
5. Connect the flange and hub/wheel cooking at last. Seven hours
until dinner; if everything Sometimes making is soli-
to the Schedule 40 pipe. To adapt the goes according to plan we’ll tary, sometimes it's social.
flange to your disc brake or hub, drill have minutes to spare! Both are beautiful things. a
a disc of wood or metal to match the
hole patterns of both parts. 9:55 We attempt to drive Saul Griffith is chief troublemaker at
otherlab.com.
6. Improvise. the spit at a recommended
1–3rpm by connecting solar

makezine.com 129

PROJECTS VINYL PCB RESIST

VINYL
PCB
RESIST

MATERIALS Etch your circuits the easy way — with a Gregory Hayes
resist pattern you make on a vinyl cutter.
» Adhesive-backed vinyl
sheets if you don’t have a By Chris Connors
vinyl cutter, send your design
to a sign-making service or There are lots of ways to etch a circuit board, but
custom sticker company. all of them create a path for electricity by preserving
and removing portions of the copper coating on the
» Copper circuit board blank board. You might have tried drawing a circuit on
» Kitchen scrub pad, sand- copper with a pen or grease pencil, or silk-screening
it, or transferring toner from a laser printer, and then
paper, or steel wool for chemically etching the board. A substance used in
scuffing the copper this way is called a resist because it resists the
» Masking tape or transfer etchant and protects the copper.
tape or similar low-tack tape
» Etching chemicals such One of the easiest and most reliable resists I’ve found is
as ferric chloride, or muriatic adhesive-backed vinyl produced on a sign cutter. This is done
(hydrochloric) acid with by sticking your circuit trace image directly onto the board,
hydrogen peroxide and then immersing the board in a chemical bath. The exposed
copper is removed, leaving just the copper traces you want for
TOOLS your circuit. Here’s how I do it.

» Gloves, rubber or vinyl
» Safety glasses
» Tray or jar, nonmetallic

such as glass or ceramic
» Tweezers (fine) or other

sharp tool like a hobby knife,
utility knife, or pushpin for
“weeding” vinyl stickers
» CNC vinyl cutter/plotter

130

1. Get a circuit board design. a TIME: 1–2 HOURS a COMPLEXITY: EASY

You can design your own circuit traces, or use A
existing artwork of proven designs. Search the
Open Circuits wiki, Adafruit’s Github reposito- IMPORTANT
ry, and hobbyist websites like diystompboxes.
com to get a taste of what’s out there for free. Double-check that your
design is the right size, and
And remember, you can also transform that you left all the correct
schematic diagrams into circuit board layouts parts on the sticker when
using free software tools (see page 44). you weeded it!

We designed this board as a super-sized B
version of the MAKE Learn to Solder robot pin.
It’s got huge traces, but people also use this
method to make fine traces.

2. Cut your design in vinyl.

Convert your board design into an image
format your vinyl cutter can use. If you bring
the design to a shop, they’ll tell you what
formats to use.

Cut the design into the vinyl with the vinyl
cutter (Figure A). If you’re using a service,
make sure the cut is scaled accurately. If the
design isn’t the right size, your parts may
not fit properly.

3. “Weed” your vinyl stickers. C D

Carefully remove the unwanted vinyl bits
where you want the copper stripped from the
board. Leave behind the parts where you want
to protect the copper (Figure B).

Some services will weed the sticker for you;
others may not. When we ordered some from
TAP Plastics, they came back weeded.

Most vinyl cutters come with fancy, sharp
tweezers, but you can use a utility knife or a
pushpin taped into the barrel of an old pen to
pick out the parts of the vinyl you don’t want.

Gunther Kirsch 4. Transfer the vinyl to EF

the copper board. masking tape. If you use very sticky tape, the
vinyl won’t stay on your circuit board.
Scuff the board so the etchant will be able
to reach the copper easily (Figure C). Circuit Use the transfer tape to lift your vinyl sticker
board blanks are treated with a clear coating off its backing (Figure D) and place it onto the
that keeps the copper from oxidizing in the copper face of the board (Figure E). Smooth
air. If this coating has been removed for any it down firmly everywhere to get the best
amount of time, you’ll see dark spots. These adhesion you can. Then remove the transfer
spots shouldn’t affect your etching. tape (Figure F).

Place your weeded sticker on a flat surface
and cover it with low-tack transfer tape or

makezine.com 131

PROJECTS VINYL PCB RESIST

5. Prepare the etchant bath. G ETCHING TIPS

Put your etchant into a nonmetallic tray Using a smaller container will
or jar with a tight-fitting lid. help you to use less liquid and
still cover the board.
Wear safety goggles and rubber or vinyl If your etching liquid is warm,
gloves, to keep the etchant chemicals out it will act faster on the copper,
of your eyes and off your skin. reducing your etching time.
You can prepare a warming tray
Most people use ferric chloride. Other filled with hot water, and place
chemicals will also work, such as muriatic your etching tray or jar in it to
(hydrochloric) acid and hydrogen peroxide. raise the temperature. Make
For detailed tutorials on both methods check sure you don’t overheat it.
out MAKE’s Circuit Board etching video at If you etch in a small jar, you
makeprojects.com/project/b/651 and can seal the lid and shake it
The Real Elliot’s tutorial on Instructables. gently to agitate it with less
risk of spilling.
6. Etch the circuit board. H
I Grab this robot
Immerse the circuit board in the bath of circuit board design
etchant (Figure G). Agitate the board from at makezine.com/go/
time to time, to keep fresh etchant working robotresist and etch
on the copper. your own. Then follow
the directions there to
Remove the board frequently to check solder a flashing-eyed
its progress (Figure H). If you etch for too robot circuit!
long, you could etch away the circuit traces.
However, over-etching is much less likely with
this technique, since the vinyl makes a very
tight bond with the board.

It’s done when the copper is completely
removed from the areas not covered by vinyl.
Take the board out of the etchant and rinse
it under cold running water.

7. Peel the vinyl off. J

Once you’re sure the copper is cleared to your
satisfaction, peel the vinyl resist off the board
(Figure I). It should come off easily.

If you really need to etch it some more, you
can, but placing the vinyl back on may be a
challenge. It’s best to leave the vinyl on until
you're sure the copper is removed.

Admire your new circuit board (Figure J).

8. Use your new circuit board.

Compare your circuit board to the original
artwork. If everything is to your satisfaction,
you can now drill out the holes for your com-
ponents or surface mount them as we did. a

MAKE contributor Chris Connors is a teacher who loves to learn with curious
people who are interested in inventing the future. He wrote the “Mendocino
Motor” project in MAKE Volume 31.

132

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BUILD NOTES THE COUNTING BOX

The
Counting
Box

134

A

How I built a
simple counting
circuit housed
in bamboo for
my son.

Written and
photographed by
Nathan Pryor

More than a few times I’ve peeked in at night to
find my son in bed with a calculator in one hand
and a flashlight in the other, sound asleep after
pushing “1 + = = =” and watching the numbers
climb until he couldn’t keep his eyes open. So,
for his fourth birthday I decided to build him a
dedicated machine that would do nothing but
count up and count down at his command.

My initial idea was simple: a large multi-digit
seven-segment LED display, two big arcade
buttons to add and subtract, and a 10-position
rotary switch in the middle. Turn the rotary
switch to choose a value from one to 10, then
push a button to increase the number displayed
on the LEDs by that amount. Push the other
button and it would go down by the same.

The Circuit

The circuit came first in this project, since the size
of the case would depend on the size of the finished
electronics package (Figure A).

At the core of it all is an ATmega328, one of the most
common Arduino processors. A pair of 4-digit LED clock
displays show the number, driven by a Maxim MAX7219

makezine.com 135

BUILD NOTES THE COUNTING BOX

LED display driver chip capable of handling 64 The LED display is on its own board, con-

LEDs, or 8 seven-segment digits, using only 3 nected by ribbon cable to the main processor

output pins on the ATmega. board. The 99,999,999 count that the 8 digits

After building the circuit on a breadboard allow is definitely overkill, but using the 4-digit

and writing a basic test program, I had my first LED displays saved a lot of wiring and solder-

introduction to switch bounce, the electronic ing compared to using individual digits.

noise or chatter on the millisecond level as a For power, I planned on using rechargeable

switch’s contacts open or close. What seems AA batteries.

like one button push to us can be read by a

microprocessor as dozens, hundreds, or more. The Software

Fortunately, the arcade buttons I ordered hap- The software has 3 primary functions: han-

pened to be double-throw switches. These dling button pushes to increase and decrease

allow a fairly simple debounce solution in the number by the selected amount, display-

hardware using 2 NAND logic gates for each ing the number, and storing the number

switch. A 74HC00 integrated circuit provided to memory.

all 4 required gates in one chip. Button pushes come through as interrupts,

The rotary switch was binary coded, so it which do pretty much what it sounds like they

was only a matter of connecting its 4 pins — would — interrupt any other actions taking

one for each of the bits required to count to place in the program. The alternative to this is

10 — to the ATmega’s input to constantly poll the button

pins, reading each and com- The Counting to see if it’s being pressed, but
bining them, then converting Box can be used this is inefficient compared
to decimal. to essentially asking the but-

Now that the circuit could to help introduce ton to let you know when it’s
count, I needed a way to being pressed.
store the current value of the mathematical
When a button is pressed,

display. You don’t want to get concepts like skip the program reads the value
your Counting Box up to an of the rotary switch, adds or
amazingly high number only counting. subtracts that amount from

to lose it when you turn the the variable, then breaks it

power off. This should be an easy job for the into individual digits to send to the MAX7219

ATmega’s internal EEPROM, but when I looked for display. In every loop, the program com-

at the specs it was only rated for 100,000 pares the current value of the variable to the

write cycles. With a display that could go up to value of the variable on the previous loop. If

99,999,999, that seemed inadequate. Instead they’re different it stores the new value to the

I found the 24LC256 EEPROM memory chip EEPROM memory chip.

with 1,000,000 write cycles — still not as high You can zero the Counting Box by setting

as the Counting Box could reach, but a lot the number selector to 8 and holding down

closer. In actual use, though, the ATmega’s the decrease button when you power it on.

onboard memory would more than likely be Similarly, setting the number selector to 3 and

sufficient. holding the increment button during power-

I did my prototyping and programming up will display statistics such as highest and

with an Arduino Duemilanove, but for the final lowest numbers reached and total number of

build I used the same ATmega chip to build button presses over the life of the box.

a standalone circuit on stripboard. I prefer To save power, the ATmega goes to sleep

a standalone microcontroller in my projects and the LED display goes dark if no buttons

because it uses less space than building in an are pushed for one minute. Pushing either

entire Arduino board, costs less, and leaves button will wake the system.

my Arduino free for the next project.

136

Building the Box B Two weeks later a package arrived with
the crisply cut wood (Figure C). The pieces
With the circuit and software done, I set were beautiful, but they didn’t fit together. I’d
specified too wide of a kerf (the width of a cut),
them both aside. They could definitely stand and in compensating for that the BoxMaker
program had adjusted the widths of the notch-
some further optimization, but their only real es to close up gaps that didn’t exist. With a file
and some sandpaper I was able to widen the
requirement was that they work. The box, notches enough to get the box together.

though, would be seen every day and had to I glued the joints, sanded a radius on all the
corners, then finished the wood with a poly-
look as good as it could. It had to be friendly urethane gloss for protection and to give the
bamboo a warm, amber glow.
to young hands and resilient enough to with-
The red acrylic window covering the LEDs
stand the occasional drop. Wood was the was laser-cut at the same time as the wood.
I was hoping for a tight fit that wouldn’t
perfect material, but I don’t have the precision require any glue so I made 6 different versions
of the window, each sized a few hundredths
woodworking skills or shop to build what of an inch larger than the last, and used the
one that fit best.
I wanted. Laser cutting to the rescue!
As I started putting it all together, I realized
To lay out the pattern of joints on the cor- I wasn’t happy with the way the AA batteries
fit into the case. They were ugly, and taking
ners, I used an online utility called BoxMaker them out for charging would be a hassle. To
replace them, I used a lithium-ion battery
(boxmaker.rahulbotics.com). Enter the outer pack and USB charger (Figure D), both from
Adafruit (adafruit.com). The 3.7V battery
width, depth, and height of your finished box, feeds into a voltage step-up circuit to provide
the 5V needed.
the thickness of the material, and the kerf (the
C
width of material removed by the cut), and
D
it generates a PDF of all the required pieces.

I imported this PDF to Adobe Illustrator,

made a few minor tweaks to the spacing

for symmetry between left and right sides,

and placed the elements like the window

cutout and buttonholes.

Before uploading for cutting, I printed the

plans and spray-mounted them onto ¼" foam

core board, then cut out and assembled the

pieces (Figure B). Foam board is a lot cheaper

than laser-cutting, so this stage is a much

better place to find errors (like a tab where

a slot should be, or a box not deep enough

to hold a button).

Not only did the mockup fit together,

but all of the components fit into it. With that

final check done, I uploaded the design to

Ponoko (ponoko.com) to be laser-cut from

bamboo plywood.

BUILD NOTES THE COUNTING BOX

EF

Like a lot of us, my son likes to look inside up with games to play with the Counting Box.
things and see how they work. The last-minute Ask questions like, “How can you get to 49 in
power supply change let me put the circuit the fewest button pushes? Can you do it with
facing outward where the batteries would have the selector switch set to the same value the
been, allowing the door on the back to serve entire time?” The Counting Box can also be
as a window for him to peek at the electronics used to help introduce mathematical con-
inside. To keep fragile wires safe, I covered the cepts like skip counting. More advanced ideas
circuit with a piece of clear acrylic cut to size like multiplication and division come quickly
and held by standoffs (Figure E). when it’s made apparent that they’re nothing
more than repeated addition or subtraction.
The door in the back of the box is held on
by four 3mm neodymium magnets epoxied I’m not sure who’s learned more, me in
into holes drilled into the door panel and the building it or my son in playing with it, but
frame (Figure F). The magnets are strong either way the Counting Box adds up to a lot
enough to keep the door secure in regular use, of fun. a
but they give when pried open using the half-
moon cutouts on each side. More at hahabird.com.

Using the Counting Box Nathan Pryor is a software developer and graphic designer who enjoys turn-
ing off the computer and building things with his hands. He has a hard time
In addition to the obvious thrill of seeing how remembering to clean up after his last project before starting the next.
high the numbers can get, it’s easy to come

138

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PROJECTS HOWTOONS

140

makezine.com 141

PROJECTS REMAKING HISTORY Gunther Kirsch

Presidential political campaigns were much
different in the nineteenth century, and
to many people, (me included) they sound
like much more fun. Instead of ceaseless
televised debates and commercials, scripted
sound bites, and never-ending media analy-
sis, the key political tool was the parade.

Abraham
Lincoln

and the

Political
Campaign
Torch ByWilliamGurstelle

Courtesy HarpWeek WHILE EVERYONE MAY STILL LOVE A Keeping Safety in Mind
PARADE, Americans of 150 years ago, it
seems, were absolutely enamored of them. 1. Use only outdoors.
Imagine for a moment you're a member of
the “Wide Awakes,” one of many political 2. Kerosene is not as flammable as gasoline
marching clubs organized to drum up support
for political candidates. Since marching is but extreme caution is still required. It must
what you do, you and your fellow Wide Awakes be stored in an approved container.
do it often and are very good at it. Everyone
in the group (and there are thousands) owns 3. Keep a fire extinguisher handy. Use
a torch. Your torch — a new gimbal-mounted,
nickel-plated tin torch in the shape of a Union extreme caution when lighting, handling,
Army musket — is particularly eye-catching. filling, or holding the torch. Never fill the
torch while hot.
When an evening march is organized
on behalf of your presidential candidate, 4. Check often to make sure the can is
Abraham Lincoln, your club takes to the
streets, waving torches with pride and art- securely attached to the dowel.
istry, even using them in the manner of rifles,
presenting a display of close order drill to the 5. Do not hold the torch too much off vertical
crowds lining the streets. It’s very exciting.
or it might drip kerosene.
Mr. Lincoln himself rarely attended actual
parades, because at the time, candidates did 1860s and 1870s, strategies such as parades
not campaign personally. They stayed home were the best way to reach people of all social
and let others make speeches on their behalf. status. However, as literacy rates rose and
But on Aug. 8, 1860, Lincoln did participate newspapers became less politically biased (at
in a rally near his home in Springfield, Illinois. least overtly) political campaigning became
He was mobbed by an enthusiastic crowd and less spectacular and more educational. By
was lucky not to have been injured. 1900, the importance and frequency of the
torchlight parade declined dramatically, and
These parades often lasted two to three the torch-manufacturing industry slid into a
hours. The costumed or uniformed participants steep decline from which it never recovered.
sang campaign songs and shouted slogans as
they marched. To satisfy the need for parade
torches, scores of small manufacturing com-
panies sprang up across the United States
to fabricate them. Their factories ran at full
steam, stamping out hundreds of thousands
of unusually shaped torches — from rifle look-
alikes for the aforementioned close order drill
ceremonies, to torches built in the shape of
faces, animals, capital letters (“L” for Lincoln),
hats, pinecones, brooms, and pick axes.

Night after night, all over the country,
people marched by torchlight, hoping
the bright lights held aloft would awaken
sympathetic feelings in onlookers and carry
their candidate to victory. But the era of such
campaigning tactics was soon to wane. In the

makezine.com 143

PROJECTS REMAKING HISTORY 1

How to Make 4
a Parade Torch

No nineteenth century political
candidate worth his salt would allow
supporters to march on his behalf
without making sure there was a
blazing torch in everyone’s hands.
Here’s how to make your own.

NOTE

If desired, you can

whittle the other end
2 of the dowel to a point

so the torch can be

staked in the ground in

your backyard.

3

5

a TIME: AN AFTERNOON a COMPLEXITY: EASY

MATERIALS 1. Drill a 3" hole centered in 5. Wrap the can with alumi-

» Metal can, small and clean the lid of the clean metal can. num foil or high-temperature
with screw-on or replaceable aluminum tape, forming a
push-on lid 2. Using JB Weld or other skirt around the can.

» JB Weld or other high- high-temperature epoxy, make Using the Torch
temperature epoxy adhesive a wick collar by gluing the hex
nut over the hole, as shown. Outdoors, fill the can one-
» Hex nut, 3" quarter to one-third full with
» Cotton rope, ½" diameter, 3. Using high-temperature kerosene, using a fill spout.

2½" to 4" long depending epoxy, glue the can to the Make sure the lid is pressed
on can height wooden dowel. Let the epoxy down securely or screwed
» Wooden dowel, 1" diameter, harden before continuing to tightly after filling, with a ½"
3' long Step 4. Check label directions wick of rope sticking out.
» Kerosene Do NOT use alcohol for curing time.
or gasoline. Let the rope wick draw
» Aluminum foil or high- 4. Trim the rope to fit the kerosene up. After 1–2
temperature aluminum tape minutes, light the wick using
can and insert it through the a long-handled lighter or
TOOLS hex nut so that ½" of rope fireplace match. a
sticks out of the lid. It should
» Drill with 3" bit fit snugly. Julie West
» Fill spout for the kerosene
» Long-handled lighter

or fireplace match
» Fire extinguisher

William Gurstelle is a contributing editor of MAKE. The new and improved edition of his book Backyard Ballistics has just been released.

144



PROJECTS HOMEBREW

146

A Nixie tube clock I’VE ALWAYS BEEN FASCINATED BY
morphs into the glow of ionized gases, but never
something new: got around to putting together a Nixie
checkmate. tube clock — the whole craze of the last
decade seemed to pass me by. When
Written and photographed by I finally decided to make one, I knew
Tony Adams it would have to be something a little
different to stand out. I wanted to do it
without wires, not just hidden but wire-
less, powered inductively by coils acting
as an air-cored transformer.

Building the first single-digit modules,
I thought they looked a little like chess
pieces. A crazy idea started to form, one
that wouldn’t go away even though it
seemed impossible to make it work.
Using this design, 64 coils would need
over 50 watts. Was there any way to
make it work with less? I guessed that
the power consumption would need
to be kept below 25 watts to prevent
overheating. Some feverish redesigning
resulted in a single-coil prototype, which
drew 20 milliamps. Yes, it could be done,
but how practical would a chessboard
with 64 individual transformers and
driver circuits be?

I bought a full-size sheet of copper
laminate and cut out a 14-inch-square
board. The winding of the coils pro-
gressed slowly over the next few days.
The case and pieces took a couple more
weeks. Finally, I set it up one evening
on the kitchen table, blogged it, and
waited for the comments. I still haven’t
recovered from the shock. Hits on my
blog exploded and I had to scramble to
change to a host that could handle the
load. I just shipped the first round of kits,
and we still don’t have a completed Nixie
clock in the house. a

Tony Adams is a freelance electronics engineer. He has been building
circuits since he was 6 years old, and has spent the last 15 years
repairing industrial lasers to keep the bills paid. He now also makes
Nixie tube chess set kits. lasermad.com

makezine.com 147

TOOLBOX

Red Clouds Collective CoffinTool Roll $45redcloudscollective.com

» I'll admit I’m a sucker for anything made out of waxed canvas and leather. The pockets

of this beautiful soft case weren't quite the right shape for my sculpting loops, so I evicted

them and replaced them with my leather-working tools — skivers, bevelers, awls, and such

— which have proven to be much happier tenants. The thick 10oz canvas was made to hold

its own against sharp slicey-dicey tools. The brass zipper pocket is roomy enough to hold

extra blades and various bric-a-brac, and the simple tie makes me feel a bit more bucolic

every time I tuck in … er … wrap up my tools at night.  —Jason Babler

Gregory Hayes

148