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Step
1:
Cutting out the Front Portion of the Light
From
the one inch square tube stock, cut two pieces that are about 1-7/8"
inch (48mm) long. The length will vary a little depending on the
particular optics or reflectors that you choose. From these 2 pieces,
cutaway one inch of aluminum from 3 sides, leaving one side intact.
This will give you the two outer, side pieces of the front portion of
the light. The long side that you left intact will cover the ends of
the main body of the light.
Cut one
other (middle) piece about 7/8" (22.5mm) . You should end up
with 3
pieces that look similar to this photo.
Tip: I
sometimes find it a good idea to cut a little long to give yourself
some extra metal for sanding and filing to get a squared, better fit.
This depends on what kind of tools you have available and your cutting
skills.
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Step
2: Gluing front portion and cutting main body
Clean (with alcohol), sand
and roughen up the inner sides of the front portion of the
light
and use J-B Weld to join them as shown in the photo. Make sure
everything is as square as possible, clamp them and let them set
overnight. (The quick bond J-B Weld does not hold as well as
the regular slower drying J-B)
Cut
another piece from the stock 2-7/8" long. This will be the main body of
the light.
Note:
The 3 pieces in the
Step 1 photo were cut with a band saw, whereas the 3 pieces being glued
in this step 2 photo were cut using a Dremel, thus look a little
rougher. A little work with a hand file will take care of most of the
rough edges.
You can build a
smaller, 2 LED light by omitting the middle piece in the front section
and making the main body shorter (1 - 7/8").
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Step
3: 1/16" Aluminum LED Backing Plate
Cut a piece of 1/16" aluminum bar (could be cut from
one side of the
one inch square tube stock if you had to) that is the length of the
body of
the light (2-7/8"). It must be narrowed to a width of 7/8". This piece
is glued to the main body of the light using Artic Alumina Adhesive. It
should be centered leaving a 1/16" space on the top and bottom edges.
Clamp tightly until the AA is set.
This is the piece of aluminum to which your LED stars or emitters will
be mounted.
It also helps make the light more structurally sound by securing the
front portion of the light to the main body. This better fit will also
aid in heat dissopation and help make the light more water resistant.
Note: In recent
versions I've started using a 1/8" thick aluminum bar for the backing
plate instead of the 1/16". It holds the front portion more securely to
the
main body and helps to better conduct heat away from the LEDs
to the front portion of the light. Now the whole light is virtually a
heatsink! |
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Step
3a: Notching Out for the Backing Plate
While waiting on the AA adhesive to cure, you will
need to notch
out 1/6" from the two middle ribs in the back of the front portion of
the light. This will allow the newly added 1/16" backing plate, added
to the main body in step 3, to fit inside the front portion of the
light. A Dremel tool with a cutting and/or sanding accessory makes this
go pretty quickly.
Note:
when
calculating the depth of the front portion of your light, be sure to
add this 1/16" to the total depth.
Generally, using reflectors will require a front
section
that is a little deeper and optics will be a little shorter. Also if
you're looking at using optics or reflectors different from the ones
that I will mention, you'll of course need to make sure that they will
fit inside the square tube (which is about 7/8" or a little over 22mm).
Of course if you choose the 1/8" backing plate, as suggested above, you
need to figure that into the depth of the front area as well and you'll
need to make deeper notches to allow for the backing plate. |
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Step
3b: Test Fitting Parts Together
Once the AA adhesive has set and you have trimmed out the requried area
from the
back of the light face, you can finally test fit the pieces together.
You might find that things fit better by flipping the body upside
down... whichever way it fits best. You might have to do some work with
a hand file to get things to fit just right. Eventually you should get
a snug fit. You might use a sharpie to mark the top side of the light.
Don't worry, the Sharpie ink will come off with alcohol. |
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Step
4: Constructing End Mounting Brackets
This step involves constructing an end mounting bracket for each end of
the light so that we have a way to securely attach the front section of
the light to the main body. Basically we will cut two pieces of
aluminum angle from the
one inch stock (one is shown in the photo) and J-B weld a nut to the
inside of the short side. Thus the short side will be the length of the
nut you are using. The width of the piece must be such that it
will fit inside the main body of the light (about 7/8")
Note:
I used #8-32 nuts and cap head bolts (1/2" long - might
need to cut length off to avoid contact with internal parts)
Note:
This is also a good time to drill holes in the main body to accept your
power connector and switch or dimmer potentiometer.
Note: In some
cases, you might need to leave one of the mounting brackets off until
you've installed all the components. For example, a 3021 Buckpuck
driver just barely fits inside.
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Step
4a: Gluing Backing Nuts
Once the two pices are cut, position the nuts near one side and mark to
drill a hole for the bolt to pass through. Next, use J-B Weld to attach
the nuts over the hole (as shown) and let this dry.
Note: I find it easier to manage the nuts during the gluing process by
screwing the bolt into it. Put a little non-stick PAM or oil or wax on
the
bolt so that J-B weld does not adhere to it. Or just be careful not to
glue your bolt to your nut!
Also it's a good idea to clean and roughen up all surfaces that will be
involved in J-B Weld adhesion.... even the bottom side of the nut. Many
metals and nuts and bolts have oil on them from machining. Alcohol
cleans them up nicely so that the J-B will stick properly.
Safety
note:
Don't try to hold these little blender blades in your hand while
drilling the holes. Clamp them down to something or use some pliers or
vice grips. |
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Step
5: Gluing End-Mount Brackets
Now that the end brackets have been constructed, they must be glued in
place inside the ends of the main body of the light. Before gluing
in place, it is a good idea to check to see that you
can pass all of your electronics and connectors into the body of the
light with these brackets in place. You might need to grind down part
of the bracket a little to get something in. Once we're past this point
it becomes a
little like building a ship in a bottle!
Once you are satisfied that everything can be installed with the
brackets in place: clean, sand and roughen the long side of
your
newly constructed
mounting brackets and the inside bottom of the light body. Once again,
using our friend J-B, attach the brackets to the inside of the ends of
the light body.
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Step
5a. Trimming End Mount Brackets for Clearance
As you can see, I trimmed this end down a little to allow me to pass
things inside easier. The trimming that is needed will vary depending
on what components must be placed inside and where they will be
situated. Be sure to practice being able to build your "ship in the
bottle" before gluing these brackets into place.
As mentioned above, sometimes it's convenient to just JB Weld one end
onto the light body after installing the components. You can knock the
bracket loose later if you must get something back out. I've done it!
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Step
6. Ready for Assembly
I made a couple of feet for this helmet version of the light. Once
again out of our one inch square aluminum tube stock!
Cut one inch of stock from the tube, then cut the opposite, diagonal
corners, giving you two 90 degree angle pieces. Dress the piece up a
little by rounding some corners and drill a hole about 3/4" up from
the bottom of the angle (19 mm or so). This hole placement will vary
depending on your helmet or bar mount design, or you might wish to
design a
different mounting bracket altogether, but this is where it will attach
nicely to the light, giving you a total of two bolts holding the whole
thing together! (OK. Two bolts and some J-B Weld!) |
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Housing
and Mount Construction Complete
The construction of the light housing is basically finsihed at this
point. The rubber fender washer between the mounting bracket and the light's
body
helps give the swivel action a firm feel without having to tighten the
bolts real tight. It should be fairly easy to reach up and adjust the
angle of your light, and at the same time having it stay in position
while riding.
I use some 1/8" thick, peel and stick, rubber padding underneath the
feet to keep the light from slipping around on my helmet. This is sold
in stores to go on the bottom furniture legs to keep things from
sliding around and scratching wood floors... very handy. You might
choose Velcro.
Getting to this stage usually takes me about 4 or 5 hours total work
although it's over a couple of days since some J-B welded parts must
set.
This is a good time to work on your light's finish if you want it to be
shiny. Sand with 200, then 400, then 600 grit wet/dry sandpaper, and
you'll get a nice polished look. Finish off with some polishing
compound if your really want a shine!
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