CIRCUITS
MATERIALS (For 1 skate)
PIC 12F629 microcontroller chip
$7 from Big Clive’s Shop,
bigclive.com.
IC socket, 8-pin DIP All Electronics part #ICS- 8,
allelectronics.com
UFO LED, RGB 3x 1-watt $10, Quickar Electronics
part #mhrgbufo,
quickar.com
Resistors: ¼ watt 1kΩ ( 3), ½ watt 47Ω ( 3)
5V, 1A voltage regulator such as an LM7805,
from Jameco Electronics,
jameco.com
2N7000 N-channel MOSFET transistors ( 3)
from Jameco Electronics
22μf 25V electrolytic capacitors ( 2)
Circuit board 1"× 1" All Electronics #PC- 1
NOTE: Alternatively, you can buy an RGB board
kit for $25 from
bigclive.com that includes
everything above except the UFO LED and the
47Ω resistors. I built my own because the kit’s
printed circuit board was too big for my skates.
Push-button switches, normally open ( 2)
All Electronics #MPB- 1
Sub-mini on/off switch All Electronics #SMTS- 4
9V alkaline battery
9V battery clip with 3" leads All Electronics #BST- 3
Plastic project box I used a 1"× 2"× 3" box,
All Electronics #TB- 1.
12" lengths of fine wire ( 4) to power the LED.
I used old printer wire.
12" length of
1" heat-shrink tubing
Semi-transparent jam plugs ( 2) $5/pair, color
GLOW, from
newskates.com
New skate boot bolts ( 8) $5 from newskates.com
1"× 10-32 machine screws with nuts ( 4) from any
hardware store
12" length of velcro tape
12"× 12"×
1" sheet of Delrin plastic $14,
McMaster-Carr part #8575K113,
mcmaster.com.
This will build 2 insulator plates.
TOOLS
Scroll saw
Electric drill or drill press
Forstner drill bits:
4" and
2"
Assorted small drill bits
Wire stripper or small bolt cutters
Wire cutter
Long-nose pliers
Screwdrivers
Soldering iron
Solder and solder wick
Center punch
Electrical tape
#220 sandpaper
File for trimming plastic
Hammer
Rubber mallet
Skate wrenches (optional)
146 Make: Volume
16
4. Remove the temporary bolts from the skate plate
and find your center mark for the UFO LED. Drill a
flat-bottomed hole (not a through-hole) with a 4
"
Forstner bit. The goal is to leave a e" layer of plastic at the bottom of the hole to serve as an insulator
between the metal plate and the LED. In the center
of this hole, drill a
2" hole through the plastic sheet,
to allow the UFO LED lens to poke through. Make a
small notch in the rear part of the thin plastic insulator (to make it easier to run the small wires for the
LED). Drill out clearance holes for any protruding
rivets at this time.
5. Using a scroll saw, cut out the outline of the skate
plate on the plastic sheet. Stay on the outside of the
trace line. Smooth the edges; sandpaper works well.
Verify the accuracy of the plastic plate against the
metal skate plate; it should fit flat. Note the square
notch for wires in the plastic plate (Figure C).
6. Solder 4 wires to the UFO LED, using very thin
wires about 12" long that will fit inside
1" heat-shrink tubing after it’s shrunk to
5". I used red,
green, and blue to indicate the LED colors and white
as the common wire (Figure D). Wire from an old
printer cable worked well for me.
My skate plate had a gap in the metal at the
back of the toe stop. Enlarge it just a little with a
1" drill bit to make a place to run the LED controller
wires (Figure E). If your plate uses a jam nut to lock
the toe stop, you may need to drill a
1" hole for
the wires.
7. Place the plastic plate over the metal skate plate
and line up the holes. Insert the LED wires through
the hole or slot in the rear of the toe stop and gently
place the UFO LED into the hole, making sure that
the shrink tubing protects the small wires from
chafing (Figure F). Place some velcro tape (the soft,
loop side of the hook-and-loop pair) over the LED to
cushion it. Reattach the boot by installing the plastic spacer between the boot and the metal skate
plate using new bolts.
8. Drill holes in the project box for the on/off and
program switches. The switches should be placed
where they’re accessible but somewhat protected
from breakage. Solder wires to the switches, then
install them (Figure G). Mount the control box to
the skate plate using velcro or screws (Figure H).
