Berger/Deveau
Home-Brew Bike Lites
Here are the instructions from Arnie Berger (Kevin Deveau's
modifications/comments are in parentheses):
I. Objectives
1-Bright, reliable, rugged (they are indeed!)
2-Reasonably portable
3-Light for 1 hour of commuting (I get 4-5 hours)
4-Looks professionally built
5-Rechargable battery
6-Switchable power levels
7-Easy to build
8-Good enough to compete with any commercial unit
II. Materials
1-One 12V 20 watt halogen flood light. GE type
BAB-$10.00 HW,LS,SM
2-One 12V 20 watt halogen spot light. GE type
ESX-$10.00 HW,LS,SM
3-One schedule 200 PVC pipe, 2" dia, 1 ft. long-$0.70
HW,PS
4-One rechargeable battery, 12V 6AH-Panasonic-$32.12 EM
5-One ATB Handlebar bag-Nashbar-$9.00 BM
6-Two SPST miniature switch, 6A rating-$2.50 LS
7-Two pin sockets for halogen bulbs-$9.00 LS
8-1/8" Aluminum Plate-app 3" by 6"-$1.00 est HW,MS (see
text)
9-Two 3/8" dia threaded electrical tube, 3/4"
long-$1.00 HW, LS
10-Four nuts and four washers for above-$0.50 LS
11-Aluminum bar stock, 1/8" by 3/4" by 8"-$0.50 est
HW,MS
12-Two small steel angle brackets-$0.50 est HW
13-One female, two-pin plug-$2.59 RS
14-Two male, two pin plugs-$5.18 RS
15-12 V power supply-$26.00 RS
16-Two female spade connectors-$1.00 HW,LS
17-Nuts, bolts, hookup wire, shrink tubing, RTV,
primer, spray paint, 5 minute epoxy glue
Notes:
(1. I suggest you use two spot lights as opposed to two
floods....this gives a slightly further viewing distance;
2.I use a 7AH battery which is not much larger than the 4AH so I get
about 4-7 hours running time;
3. Instead of the handlebar bag I first mounted the battery under
the seat in a rear pack and secured it well. I found that the
weight of the battery was noticeable on rough rides. I
subsequently packed it in bubble wrap and stuffed it in an
aluminum can which I attached to the water bottle cage mount just
above the bottom bracket (2 screws on the vertical post). I used
two large washers inside the can so the screws won't pull through
the metal.;
4. Instead of using pin sockets for the bulbs I attached two female
spade connectors (one on each pin) which works great;
5. Instead of using the male and female pin connectors I decided on
male and female spade connectors....they seem to work fine but I
may change them if I encounter problems with disconnecting;
6. I didn't use two steel brackets to attach the lights.....at first
I used two hose clamps which went around the aluminum plate and
my handlebars but now I use one clamp which goes around the bolt
used to tighten the handlebars (more later). ***The bulbs have
an integral reflector AND protective glass covers!!!***
HW=Hardware Store LS=Lighting Store PS=Plumbing Supply Store
RS=Radio Shack SM=Supermarket EM=Electronic Mailorder (DigiKey)
BM=Bike Mailorder MS=Metal Supply
III. Construction
This assumes you have some basic tools at your
disposal. If not, buy a commercially made bike light.
Otherwise read on.
1. Cut the PVC pipe into 6 sections as follows:
1-Two pieces - 3" long
2-Four pieces - 1/2" to 3/4" long
I suggest using a radial arm saw so the ends come out
smooth and square. I used a mitre saw which worked
fine but you may need to do some finishing work with
sandpaper. Don't buy the thick wall PVC pipe which is
commonly sold. Schedule 200 has a wall thickness of
1/8", rather than 1/4". The lamps fit inside of the
schedule 200 pipe, but the thick wall pipe will need to
be machined out. Also, its lighter and stays cooler
than the thicker material.
2. Cut a section of about 3/4" in length out of each of
the 4 PVC rings.
This will allow you to collapse the diameter of these
rings and slip them inside of the 3" long pieces.
These split rings will become the lamp support and will
form an internal shoulder for the aluminum disk which
will form the rear of the lamp housing. The hardest
part of this project is making the back of the lamp.
This is how Arnie did it, if you have a better way let
me know.
3. Mark two circles, about 2-1/8 diameter on the
aluminum plate.
4. Drill a 3/8" hole in the center of each circle.
5. Rough cut each circle using a sabre saw with a metal
cutting blade. Be sure to stay outside of the marked
circumference of the circles.
6. Insert a 3/8" bolt through the two disks and lock
them together with a nut. Place a washer on either
side of the disks to help hold them securely in place.
7. Put the body of the bolt in a 3/8" drill and clamp
the drill in a vise (a drill press would be even
better). With the disks spinning, file the rough
circumference until the disks are round, smooth and
just small enough to fit inside of the PVC pipe. Don't
get carried away here. It is easy to remove too much
material from the disks.
8. Carefully locate a point on the radius to drill a
hole to mount the on/off switches. They take about a
1/4" hole. The hole should be about 1-1/4" from the
centre of the disk. You will need to locate the hole
far enough out to clear the mounting hardware but not
too far to interfere with the PVC ring that will form
the rear lip to hold the back of the lamp enclosure
(aluminum disks) on.
9. Drill the holes
10. Sand the inside of the PVC pipes near the rear,
sand the outside of two of the PVC split rings and sand
the edges of the aluminum disk.
11. Wipe all the pieces clean. Mix a batch of epoxy
and spread it around inside of one of the pipes, at the
end. Also spread some epoxy on the outside of one of
the split rings.
12. Compress the split ring and insert it into the
pipe. Try to avoid pushing all the glue into the pipe,
this glue is needed to hold the split ring to the pipe.
13. Recess the split ring about 1/16" into the pipe.
Be sure there is ample glue around the lip that you
just formed and place the aluminum disk into this gooey
mess. Press down, forcing the glue around the disk and
further recessing the split ring until the aluminum
plate is flush with the rear of the pipe.
14. Wipe up the excess glue and set aside to dry.
Repeat for the second pipe and disk.
15. After the back is firmly attached, glue the
remaining slip rings to the front of the pipes. Recess
them about 1/4". These rings will hold the bulbs.
Before the glue sets check that the ring is not cocked
in the pipe. It should measure the same distance into
the pipe around the circumference.
16. When the glue is completely dry, sand the outside
surface of the pipe and aluminum disks with fine
sandpaper.
17. Wipe them clean and then paint with two coats of
spray primer. Only paint the outside of the holder and
the 1/4" recess where the lamp will sit.
18. Paint with gloss black spray enamel. When dry,
your lamp holders are complete.
**(You can skip steps 3 through to 10 [making the back
enclosures]. Instead of doing this I picked up two PVC
caps which slide over the back end of the PVC pipe. I
simply glued the caps on and voila, instant back
covers. Before you glue the covers on make sure you
complete steps 10, 11, 12 and 13 ignoring the comments
about the aluminum plate. You should still follow the
instructions on how to drill the hole in the back cap
to mount your switches. Don't glue on the caps until
you actually wire up and mount your switches because it
is impossible to solder the wires once the switch is
mounted.)
Mounting Bracket
19. Cut two pieces of the 3/8" threaded tube, 1/2" long
with a hacksaw. Try not to damage the threads too
badly. I wrapped masking tape around the part that I
held in the jaws of the vice. (Before you begin
cutting, thread a nut onto the tube, that way after it
is cut you can thread/remove the nut over the rough
threads and form them back into their original shape.)
20. Decide how far apart you want the lamp holders to
be. Arnie's are about 3.5" between centerlines but he
suggests about 4.5". (I put mine 4.5" but I would like
them about 5-5 1/2" to give me room for my brake
cables, etc. to fit in between).
21. Cut the aluminum bar to an appropriate length, 5"
for example.
22. File the rough edges of the bar.
23. Drill a hole at each end, about 1/2" in from the
ends. These hole should be slightly larger than 3/8"
for clearance. (The threaded tube will be bolted in
these holes.)
(The following 2 steps I didn't quite understand)
24. Place the steel angle bracket on the bar so that
the right angle part comes out about in the middle of
the bar.
25. Mark the locations of the holes and drill two
mounting holes in the aluminum bar. This will be the
attachment point to the mating bracket that you will
secure to your bike.
25a. (Instead, I took one angle bracket [shaped like an
L] and drilled two holes on one arm of it. I then used
a hose clamp to attach the L bracket to my handlebars.
On my bike the bolt that is used to tighten the
handlebars has enough of a lip that I could cover the
head of the bolt [used to tighten the handlebars] with
the arm of the L bracket with no holes and use the hose
clamp to secure it. This leaves the other arm of the
bracket [the one with the two holes I drilled] to
attach the aluminum bar which has the two lamp holders
attached to it. I used wing nuts for quick release.)
26. Connect the housings to the aluminum bar by using
the two, 1/2" long threaded tubes and the nuts and
washers.
Wiring
27. Check the length of the wire so that enough slack
is present to allow the bulb to be fully removed from
the PVC pipe holder.
28. (You should have 16 or 18 gauge wire consisting of
two separately insulated strands. Cut one strand about
6-8" or at a length where one end can be connected to
the switch and the other to the bulb and still allow
you to remove the bulb from the holder.
29 Solder the wire to one lug of the on/off switch.
(depending on what type of switch you are using you may
have to thread the wire through the hole in the back of
the light before you solder it depending if your switch
is mounted from the back or from the inside of the
light holder.)
30. Attach the other end of this wire to one pin of the
bulb using the female spade connector.
31. Cut another piece of wire about 8-10" in length or
long enough to reach from the bulb out through the
threaded tube where it will connect to a wire running
to the battery. Attach one end of this wire to the
free terminal of the bulb using a female spade
connector. Thread the other end through the threaded
tube (this will connect to your battery).
32. Cut another piece of wire about 8-10" in length and
solder one end to the free terminal of the switch.
Thread the other end through the threaded tube.
33. Do the same for the other lamp holder.
34. Take one wire from each lamp, join them together
and attach a male spade connector. Do the same for the
remaining two wires. Polarity does not matter.
35. TEST THE CONNECTIONS. Temporarily attach the
wires to the pos and neg terminals of the battery and
see if the bulbs light.
Setting the bulbs
36. Remove the bulb from the female spade connectors
and set aside.
37. Lay a bead of RTV silicone on the inside lip of the
holder.
38. Reconnect the bulb and then carefully, put the bulb
assembly in place on the RTV bead. (This takes some
practice......my first attempt ended with silicone
everywhere but my second attempt was perfect.)
39. You should have enough silicone that when the bulb
is set a tiny amount squeezes up around the bulb. I
then ran the end of a flat tip screwdriver around the
edge [like a trowel] scooping up excess silicone and
leaving a nice smooth finish to boot. Try to minimize
the amount that the bead overlaps the active surface of
the bulb, since this will diminish the light output.
40. Set the lamps aside to dry. There are several ways
to hold the bulbs in place while they dry. Arnie uses
a small (3/4" by 1") scrap of wood placed on the
surface of the bulb and held in place by a rubber band
around the back of the light. I used a VHS cassette
placed upside down (so the two drive holes face up) and
set the bulb holders on this. The switches, which
stick out of the back, rest neatly in the holes of the
VCR tape. I then set 35mm film holders or spools of
thread on the surface of the bulb then put something
heavy on the spools. Arnie's method is easier but I
had no elastic bands.
Battery
Since the length of the power cord from the battery
to the lamp will depend upon the mounting location,
let's ignore that for the moment. Whatever length of
wire you choose, you'll need to do the following:
41. Cut a length of 2 conductor wire to length.
42. On one end connect two female spade connectors (or
male depending on what you used on your lamp
wires.......make sure they are opposite). On the other
end connect two female spade connectors (these will
attach to the terminals of the battery so make sure
they are compatible). This is VERY IMPORTANT.....take
one wire from the two conductor wire and mark each end
with tape, paint, etc. Make sure that you mark both
ends of the same wire, i.e. make sure the two conductor
wire running from your lights to your battery is
polarized. Some wire is marked with a stripe. This is
not important for running the lights but it is
important when charging the battery.
43. Attach one marked end to the positive terminal of
the battery and the other marked end to either of the
lighting wires. Now attach the remaining wire to the
negative terminal of the battery and the remaining wire
from the lights.
44. I'll leave it up to you where and how to run the
wire from the battery to the lights since it will vary
according to where you mount the battery. As
mentioned, I have mine mounted just above the bottom
bracket inside the frame. It is wrapped in protective
packing then placed inside an aluminum box then wrapped
in duct tape so it is not easily removed, i.e. it stays
in place on rough rides.
45. The charger depends on what type of battery you
use. I have a 12V 7AH gel cell so I use a 12V power
source putting out less than 2 A of power. Gelcels
need constant voltage charging whereas Nicads require
constant current. See the 'net' for explanations of
this. WHEN CHARGING I DISCONNECT THE LIGHTS UP NEAR
THE HANDLEBARS AND PLUG THE POSITIVE WIRE FROM THE
CHARGER INTO THE MARKED SPADE CONNECTOR (WHICH RUNS TO
THE POSITIVE TERMINAL OF THE BATTERY) AND THE NEGATIVE
WIRE FROM THE CHARGER INTO THE UNMARKED CONNECTOR.
N.B. -I suggest using a slow burn inline fuse somewhere
in the system so prevent the risk of shorting something
out if a wire disconnects.
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