Introduction: Night's Sky Star Lamp
This Instructable shows you how to make your own custom date and place star map lamp, enjoy!
After researching different sites I found a really neat one on which you can view and download an image of the nights sky star map from any given date in the past and location from all over the world: In the Sky
If you hit up the sky charts, you can select a location, date and time to view the sky star chart and download it in different formats: Sky charts
The neat thing is that you can get the image from a place and or date that has a nice memory or event for someone.
So I wanted to convert the picture to something physical and thought it could be neat to build a lamp with it since I needed one for my bedroom when I moved.
I planned to make a round, back lit, wooden board with little holes in it to display the stars. I'm using LED strips to light it all. On the outer perimeter there will be another LED strip to shine some more light outwards and to form a contrast. I used white LEDs for the stars and warm white, yellowish, strips for the outer lighting.
- Plywood. I used 18mm plywood and concrete plywood and 12mm plywood.
- Plenty of flexible LED strips and a power source.
- Paint, I used white for the interior of the lamp and night blue for the outside.
- Depending on how you can make it a CNC cutter/waterjet cutter/ laser cutter or good skills with a bandsaw, a drill and some screws.
Step 1: Getting Your Own Star Skymap
So in the sky chart of in-the-sky.org you can select any place on our planet Earth, a date and a time in the present or past and get a visual representation of the stars above that spot. Different layers can be selected like names of constellations, different amounts of stars, lines etc.
Once you are happy with how the the map looks, you can either download it as an svg vector file or a jpeg.
I continued working with a SVG file. At work I have access to a waterjet cutter. Usable alternatives would be a laser cutter. Even simpler would be printing it out, sticking it on a wooden panel and manually drilling out all the stars.
Step 2: Editing the Image
To get to a usable image for the machine I'm using, I have to edit the image to get to only cutting lines that don't interfere with each other.
I used software called Omax Layout to get to this. Adobe Illustrator or free software like Inkscape is surely very usable as well. The first image in this step displays how the raw SVG image from the website comes in.
Since I clearly want to show all the constellations in the sky map as well, I enabled these lines connecting the stars. However, cutting these and the circles would mean that big pieces from the wooden panel would fall out.
To get a vector image I could use, I created an offset from 2 to 5mm to each star circle that intersected with a constellation line. Then create a intersection between the line ann circle and remove the undesired lines to hold everything together if its all cut out. I don't really recommend doing it this way, I probably clicked my mouse buttons for a couple of thousand times :) ...
Much easier would not using the connecting lines anyways or using a printed out version instead.
Step 3: Assembly Layout of the Lamp
To form a base and a solid attachment to a ceiling, I designed a simple assembly.
The vector file I designed for the pieces can be downloaded as a DXF from here.
First off is the suspension to the ceiling. It's a triangular shape with hooks at the end to which the base of the lamp itself can be inserted, turned and locked into place. I wanted the lamp conveniently separable from the base if I want to change anything in the future.
The lamp itself consist of tree layers which are held together by screws:
- The base. This 18mm plywood base has three holes to be hung at the ceiling suspension. I use a base that is 80cm in diameter.
- The middle ring. This 18mm concrete plywood ring has pre-drilled holes for perfect alignment with the base. The sides offer space to attach the inner and outer LED strips. The ring is slightly smaller in diameter to hide the outer LED strip somewhat.
- The sky map. This piece has the same diameter as the base. I used 12mm plywood for the sky map. Once perforated with all the holes, LEDs will light these up.
Step 4: Prepping the Wood for Cutting
For the construction I'm using different kinds of plywood. I used 18mm plywood for the base.Then the spacer and the hooks for the ceiling are 18mm concrete plywood. The sky map itself is 12mm plywood.
Since painting after drilling would make it hard not to clog up all the holes, it's better to do the color beforehand. Since I'm using an abrasive waterjet cutter, it will chip the paint here and there but I'll touch that up in the next steps.
Before applying the deep blue two times, I gave it a proper gray primer. Make sure to let the paint dry properly according to the instructions to make sure it doesn't get messy later.
Step 5: Cutting the Pieces
I used a water jet cutter to cut my plywood. Proper tools will also enable you to create these simple shapes. As long as the circles come out nicely.
First I cut out the 18mm concrete plywood suspension pieces, then the 18mm plywood base and the 18mm concrete plywood middle ring and finalized with the 12mm plywood star side.
The latter took a while since it has so many holes and lines that have to be cut individually. Again, printing the map out and doing this all by hand is very doable with some perseverance and patience. Also depends on how many stars you've selected before downloading the map.
Step 6: Paint and Touch Ups
To make the most out of the back-light through the little, cut holes, I painted the inside of the base white. Therefore I also temporarily fitted the ring to paint only the necessary surface.
The downside of cutting plywood with a waterjet cutter is that the surface de-laminates here and there.If you use a drill or even a laser this shouldn't be much of a problem.I fixed those spots applying some generic wood filler, light sanding and paining the whole top surface over with a foam paint roller. I made sure to use minimal amounts of paint, avoiding filling cut lines or holes that would block light.
Painting after cutting is an option but it would require some more time and effort to apply thin layers without blocking small holes.
Once all dry, apply a layer of clear lacquer to seal it all in.
Step 7: Lighting It Up
I got myself two kinds of LED strip, one bright white for the inside, one warm white for the outside. Unfortunately I got myself 12V and 24V strips. To use one power source, I split the necessary length of the 12V strip in two and put them in series by soldering the negative of one end to the positive start of the other. The 12V and the 24V are arranged in parallel. Safe yourself the hassle though and get strips that require the same voltage! :D
The power source's cable splits in two basically powering the LED strip on the outside and the strips on the inside. Most strips have adhesive at the back so it's easy to install. Always test and check if everything is functioning correctly before closing things up. Especially if soldering is involved.
I used white wires to not show through the holes at the end and traced the access to the back of the lamp.
If it's all good, place the top end, the star map, on the ring to seal the inner LEDs and close it all up with screws.
Step 8: Install and Enjoy!
The suspension piece comes together by screwing the hooks to the triangular base square to each other. Make sure the opening either all face clockwise or counter-clockwise.
To get it on you ceiling, use a proper way to connect it. I used 7 screws in my ceiling material and it forms a very solid base that can hold some proper weight. I used a wire outlet in the ceiling to attach the LEDs it in a safe way. If you're not familiar working with mains voltage, just use the probably long power cord delivered with your LED strips and safely put the plug in an existing socket.
To hang the light itself can be tricky but it is a lot easier if you can reach it easily by getting some good height on a little ladder for example. The trick is to insert the base with its three holes in the hooks all together and then turn it so the base rests on the hooks' cutouts.
If everything is safely in place and hooked up..... Light it up!
Some afterward thoughts:
- I still want to add some more light in and out to get a bit more detail in the stars and more usable light coming from the outer ring.
- The constellation lines form an interesting image, but also clutter it a bit. I thing it would be a bit more usable if the diameter of the lamp is even larger.
- I want to hide the LEDs on the outside by putting some diffuser over them to even out the light sources.
- I made a little error that the outer stars of the map are blacked out by the ring that is sitting underneath it. Make sure your sky map fits inside of this middle ring.
- It might be better to use a thinner material for the star chart for more light to come out of the little holes.
Overall turned out to be a really nice project that adds a original piece to my bedroom. The representation of a date and place of the image makes it all the more personal.
More of my stuff can be found on:
Second Prize in the