Introduction: LED Bethlehem Star for Outdoors / Roof
A decade ago I made a large plywood Bethlehem star lighted with C9 bulbs for my rooftop. It weighed about 20 pounds and I made a large and unwieldy mounting frame that straddled the roof peak. It looked great but was a lot of work to put up and take down. I needed something smaller and easier to handle.
Thus this LED version was made over the course of 2 days, just in time for Christmas.
The body is a piece of corrugated plastic (the type used for political signs) with holes drilled out for LED lights, the lights hot glued in, and a few pieces of wood screwed to the back of the plastic sheet to give it some rigidity and allow for mounting.
The device is attached to the chimney with rope.
I’m not able to take a good pic of it at night, but it really looks good, and it is very easy to put up and take down.
Corrugated plastic sheet (reused a political sign) 18x24”
Two sets of 100 mini LED lights, cool white
One set of 100 blue mini LED lights
Hot glue gun and glue sticks
8 pan head screws
Two pieces of 18” long dimensional wood to make a frame
Black duct tape
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Step 1: Assemble Materials
Gather tools and material
Spray paint one side of the plastic sheet with a few coats of flat black paint
Step 2: Decide on Star Shape and Dimensions
I went with a simple set of intersecting lines at 90 and 45 degree intersections.
I recommend using a meter-stick and just deal with units of 10 cm rather than mess around with inches and fractions
Step 3: Prepare Plastic Board
1). Spray paint one side of the board with several coats of black, preferably flat black
2). Draw the lines on in pencil
3). Mark off even space spots for the lights - 2cm is a good number and therefore it helps if all of your lines are even numbered lengths
Step 4: Drill Holes
Typical led lights need a 3/8” hole to fit snugly in. A regular drill bit, or a paddle bit, would make a mess of it and I didn’t have hole saw that small, sooo...
I made my own. At Ace hardware I found the hobby section where they have small pieces of aluminum and brass tube and plates. I selected a 3/8” OD brass tube.
The tube was 12”, I cut off a 5” piece to work with. I put the 5” piece in the chuck of my drill and sharpened the exposed end by running the drill while holding a small file INSIDE and sharpening the inside edge.
Obviously this could be dangerous - hands holding a spinning tool and a stationary tool etc - so go slow. Or feel free to put the drill in a vice or even use a lathe if you are fortunate enough to have one.
The problem with this type of drill bit is that you don’t have a tip to place on the pencil mark where you want your hole centered. The solution was to make a drill jig out of plywood scraps. I didn’t take a picture of it but it’s simple:
Two pieces of approx 2”x6” plywood (1/2 or 3/4). Glue them together. Drill a 3/8” hole about 2” in from one end STRAIGHT, PERPENDICULAR down thru it.
Now, simply lay the plywood jig on the sign and center the pencil mark in the hole, press down firmly and drill holes.
A lot of holes.
The tube will collect the plugs and you will need to stop after 4 or 6 holes, remove the tube from the chuck and clear the tube by pushing a screwdriver or something else thru it. If you have a waste basket nearby this will make cleanup a cinch...but the process is tedious. Expect that to take an hour...
Step 5: Glue in Lights
Using gloves and/or needle nose pliers: apply a healthy bead of hot glue around a light and put it in from the back. It will be a friction fit and the glue will set up quickly.
Some of my lights were glued in a little wobbly (see photos) and they look terrible up close - however that detail can’t be seen when the star is up on the chimney.
Glue in the lights. I chose all white lights for the shape of the star and blue lights of the rays projecting out from the star.
This seemed to take forever but I was doing it on a work table I setup in the house so I could listen to tv while I was doing it.
Test the lights occasionally as you work along.
Step 6: Attach Frame
All of the wires are piled up on the back of the board, so the board can’t be secured flat against the chimney.
Drill holes on the frame boards, nominally 1” placed 2” in from the end. Rope will be passed thru those holes to tie the unit to the chimney.
Attach two pieces of dimensional wood, one along the top, one along the bottom, behind the board. I used construction screws with a flat head for more surface area holding.
Since I had some leftover pieces of plastic board I painted two strips and cut them to the same width as the wood board. Those were screwed into the edges of the board to cover the sides.
Note: since all of the lights are lit, and unused lights are tucked up behind the board, when the unit is powered there is some light that leaks out of the sides - so the purpose of these two strips is to cover the sides and contain that light. The wooden frame could be used on all for sides to solve the same purpose, but I felt that would add unnecessary weight.
I then covered the joint between the two pieces of plastic with black duct tape
Step 7: Attach to Chimney
Loop rope around the chimney and secure to the holes in the frame.
Run and extension cord to the light and plug it in.