Intro: Space Invaders Chandelier With Glow in the Dark Action
Use 3D modeling/printing, laser cut acrylic, resin casting, UV reactive pigment, LEDs and some simple wiring to make a high style and retro cool space invaders chandelier or lamp. I've included a nice trick for making curved corners out of laser cut acrylic, a lot of info on making the relatively difficult molds to cast the parts and a fairly complete blender tutorial for building your own printable shapes.
This was originally intended to be a full ceiling chandelier, but I really couldn't come up with anywhere to put it, so I made a table top version. If you make a proper chandelier please post pictures!
This project runs on a 9 volt battery. I made this decision because any responsible person knows they need to change their smoke detector battery periodically whether it needs it or not. This is a great use for that not yet used up battery (which is used by almost no other appliance!) It is also made with laser cut parts (which can be super efficient if you're smart about it) and the resin glows in dark enough to cast a substantial amount of light even when it's not turned on at all. It uses LEDs, but that should almost go without saying because everything that can use them should at this point!
Step 1: Supplies and Equipment
Resin (I use polyester but epoxy resins are safer. Either will work.)
Silicone mold maker - Amazing Mold Putty specifically. This is the only kind that worked for me.
PVA Mold Release
3mm White LEDs (and related resistors)
Battery Snap for a 9 volt battery
Copper Wire (I used 24 gauge)
Shrink Tubing - a small size and a fairly large one that fits over resistors
Switch - I used a retro-ish large red push button, feel free to use any kind that you like.
Solder (rosin core)
Glow In the Dark Pigments
Craft Wire (20 gauge)
Jump Ring - 4mm were my choice
Jewelry Chain - well under a foot
Soldering Iron and Solder Sucker
Pliers (needle and round) and Wire Cutters
Paper Cups (for mixing resin)
Blender or another 3D software
A 2D vector program (like Illustrator)
Small Clamps (the more the better)
Sanding Supplies - a Dremel with sanding bits is nice, sandpaper works quite well, too.
Toothpicks, dental tools, needle files and any other small tools you have around
A drill with 1/16" drill bit
Acrylic Cement Needle Applicator
Resin is made of magic and toxins, so eye, breathing and hand protection are a must. Gloves should be worn any time you're near it. Protect your eyes and lungs as well. The same goes for sanding, drilling, using acrylic cement or anything else that seems unsafe. Use good judgment.
Step 2: Blender Basics
Blender is available to download for free at blender.org. It comes with a lot of superpowers but it does take a bit of time to get used to using it. It was designed to be efficient to use but that means it might not be as easy to learn as other software. In opinion, for the power and price it's more than worth learning a new way to work. My downside was that when I was using Illustrator afterward I kept wanting to just press the 'z' key for an undo.
For starters, not everything is in a clickable pulldown menu. You're going to need to memorize a few things (they'll come naturally to you soon enough.) Here are a list of handy commands I used in making this. There are a lot more. I use a Mac, so if you're using something else it would be worth checking into the help pages - I know there are some places where the three button mouse can save you some effort, but everything here should work universally.
*Be sure to check the image notes below, they'll give you a lot of useful information.*
'apple' + 'z' is undo. You won't find 'undo' in the menus, it took me a while to get used to that.
'x' is used to delete whatever is selected.
'a' is to select all - hit it again to select none.
'b' accesses the border select tool. Push 'b', then click and drag to select what you want.
'apple key + click' selects an object, face or point - hold down shift to select additional objects/faces/points. (This is a right click if you're using windows.)
'e' is used to extrude a shape.
'+' and '-' are used to zooming in and out, respectively.
You'll need to do the following to start each object:
When you open Blender you'll have a single cube in the middle of your screen, as well as a couple of objects for rendering your object, which we won't be using. Select those other two objects and delete them.
At the top of the workspace there is a header bar - click and drag at the bottom edge down to expose the preferences menus. Under 'Snap to Grid' click on 'Grab/Move' to activate it. While you're there, if you're on a Mac make sure "Emulate 3 Button Mouse" is selected as well.
Select the cube, then switch into edit mode by clicking where it says "Object Mode" just under the gridded screen.
It is a good idea to save different versions of your object as you work, especially if you are going to try something you aren't sure about. I can be very difficult to undo more than a few changes.
Step 3: Layout of Pixel Shapes
These are the shapes of standard Space Invaders 'characters.' You'll need to model each in 3D.
Step 4: Make an Easy Shape
The first object I'm going to walk through building is the tank that runs across the bottom of the screen.
Use border select to select the right side panel of the cube. Extrude it to the right one segment on the grid by pushing the 'e' key dragging the mouse to the right, and then clicking when it's in position. Keep repeating this until you have an object 8 squares wide. You may have to zoom out to fit it all on the screen. Deselect everything.
Select the left side of the original cube. Extrude it in the same way until you have a bar 15 squares wide. Deselect everything.
Again using the border select, select the entire bottom of the object. Extrude the whole thing down one square. Repeat this until your object is four blocks tall. Deselect everything.
Use the border select to select the tops of the center 13 blocks. Extrude them up one square, then deselect.
Select the tops of the center three blocks and extrude upward twice. Then top of the 1 centermost block and extrude it upward one square.
This is a finished object at this point. You will need to resize it but I will cover how to do that in the file setup step. Save this and start a new object (under 'File' in the header.)
Step 5: Make a Really Complicated Shape
This is the process for making the most complicated object, one of the small aliens at the top. It has a lot of holes and narrow connecting pieces. If you can get through making this you should be able to extrapolate the process into any of the other objects. I split this into two steps because there were so many images.
Start out by extruding a shape that is the full block of the object. Extruding in one block increments is important for editing later. Extrude the beginning cube to the right until it is four blocks wide, then to the left until it is a total of eight segments wide. (I do this to keep the object reasonably well centered in the work area.) Extrude all of that up one block. Then extrude up the center 6, then 4, then 2 blocks. Extrude the entire width down three more rows, the entire height should be 8 blocks.
At the bottom of the gridded screen click on the triangle icon to switch into face select mode. Select the square of the right 'eye' of the alien (apple key + click or right click). Push the 'x' key to delete it, then click on 'Faces' to only delete the face. Because the object is three dimensional you have to repeat that in the same place to remove the back face's 'eye' as well. Once you've done that you should have a hole through the object. Do this same thing for the other eye.
Select the lower three block rows with the border select, then click on 'subdivide' in the mesh tools category at the bottom of the screen. Click it again. There should now be 16 small squares where there used to be one big square.
Step 6: Complicated Shape (Part 2)
You now need to delete the faces that comprise the other holes. The idea is that, of the four rows of four holes, you leave a row on either edge behind - for example, a square hole would mean deleting 4 boxes high but only two boxes wide. Follow the images below for a clearer view of this.
After you have all of the required faces deleted, you need to nudge some things around.
Switch to point select mode, then push 'g', 'x' (for moving on the x axis) and then how far - in this case, .2. You can use a -.2 as well, depending on what direction you need to move things. If you make a mistake you can use the esc key to cancel it, or apple z to undo it. Nudge things until they look like the last image - this is just to refine the openings a bit.
Step 7: Complicated Shape (Part 3)
Every object needs to be watertight to be printable. If you turned this one to the side right now you would be able to see right through it. We need to add some faces back in where we deleted some before.
Use border select to select any two points (from the front - that's 4 total) and then use the 'f' key to make a face. Deselect those (a), then do it again everywhere you need a face, with the exception of the corners (as labeled in one of the images below.) There are probably faster ways to do this, but this method if very reliable for making a printable object.
After the easy ones are done, rotate the object (hold down option while you click and drag) to see a corner spot. Select three points, then use 'f' to make a face. You'll need 5 faces for each corner.
When you think you're done, hit the space bar, then go to select > non-manifold. Anything it highlights will be a place where you missed something. Keep working on it until the non-manifold doesn't highlight anything.
Step 8: Export Shapes and Print Them
If you're using Shapeways, you need to scale your object and export it for printing. 1 = 1 meter, so adjust accordingly. Space > transform > properties will open your properties menu. In object mode you can adjust the numbers to be the right size. These are about 1.5cm tall and about 8mm thick. I had the best luck with exporting as a .x3d for Shapeways.
Make an account at Shapeways, then upload your piece. The system will tell you if there's a problem with it. If there aren't any problems it will give you a price for printing. I used the basic white plastic for mine because I was only making molds. You can reduce your cost by putting an empty space inside your shapes (be sure to reverse the normals on that inner shape.)
In about 10 days you'll have a little box of parts arrive. That box was so much fun.
Step 9: Make Molds
You'll to clean up your new pieces a bit (a straight pin works great), as they usually have a bit of dust and grunge on them. Once that's done, make your mold by measuring out the putty in two equal pieces, mushing it together until it's one color (as quickly as possible), then getting to work on your mold.
First, smoosh as much of it into the holes as you can. For real. The denser that silicone is the better. Then wrap the rest of the silicone up around the sides, and push it down onto a flat surface so it will be level when you cast into it. Let it set up all the way - leave it for at least half an hour.
I chose the silicone I recommended because it's tough and has an oily surface. You'll need to carefully work your piece out of the silicone, push down on the silicone in the holes a bit to encourage it to slide out instead of tearing off inside the eyes. If it does tear off you can push a bit of 24 gauge wire through it and into the base so the mold will still work.
Make at least one of each piece, making a few with make things a lot easier.
Step 10: Cast Pieces
For best results you'll want to paint the insides of the mold with a mold release before casting. Let it dry COMPLETELY before you pour in your resin.
Mix the glow in the dark pigment into the resin before catalyzing, or mix it into half before mixing the two parts. Because it's a powder it doesn't disolve in like a dye would, and you need to keep mixing it while you cast to keep it from settling.
Pour a bit into each mold, then use a pin or toothpick to draw the resin into the smaller detail areas. Fill it slowly the rest of the way to prevent air bubbles from getting trapped.
I pulled my pieces before they were completely hardened, this seemed to be easier on the molds. Coax the mold through the holes in your part with a toothpick to reduce mold stress.
Step 11: Finish Your Pieces
First of, soak them in water for a while. This will remove the mold release and any other random debris.
You'll probably need to do some sanding to them in the best shape - I use a dremel with a sanding drum for most of it, and needle files to fill in the details. It takes a while, but it's worth it.
Drill a hole straight down the center of each piece. Using a 1/16" bit will give you hole large enough for wire but thin enough to be subtle. Do this slowly and carefully and use safety glasses - hot plastic will fly at your face.
Step 12: Lamp Base
You'll need to have your lamp parts laser cut - I used 1/8 black acrylic.
Attach loops made from head pins to the two rows of holes for the top piece. Put a pin through the hole, bend it over, cut it about 3/8 inch, then use the round nose pliers to roll the wire into a loop. This is where the stands of invaders will hang.
This is easiest to do now. Glue up the inner frame with the acrylic cement and let it dry completely. The pictures below show the steps, just make sure to glue up either stacks of 9 pieces and accept a small gap, or stacks of 10 and sand the pieces down to fit. Glue everything into a ring before wiring.
Step 13: Wiring
Wire up your LEDs before gluing it the rest of the way. Check them all on a 3 volt battery to be sure they light up. Push them all into the frame at once, making sure all of the positives are aligned. Bend the leads one direction (away from the battery area).
Every place that you solder pieces of wire together you need to twist them together neatly first. This is an inline splice, and you can find instructables devoted just to that if you want more info!
Solder one resistor onto the ground (negative) lead at every other LED. I think the best way to do this would be to wire two LEDs in serial on the resistor, but my LEDs wouldn't light up in serial so I did pairs in parallel. Solder on all of these resistors at once.
Next cut pieces of wire long enough to go from one LED to the end of the lead on the next. Solder these pieces on to the available ground leads. Again, do this all the way around.
Get your shrink tubing going - cut a piece a bit longer than the space from one LED to the next. Slide it on to the first ground lead, and heat it with the heat gun to shrink it.
Wrap the rest of this short wire around the next ground lead (with the resistor already soldered on). Reheat the solder a bit to connect all three.
Using a larger shrink tube cut a piece to go over this section, slide it over the resistor and heat it.
Repeat this until you run out of ground leads, but don't bother with the shrink tube on the very last one.
Cut one piece of wire long enough to go all the way around the inner ring plus enough for one more side (5 sides of the square). Starting at the first resistor lead, solder the lead to the wire. Shrink tube the length to the next resistor, and do it again. The idea is to get all of the grounds wired together to the very end.
Do the same thing on the positive side, but this is much easier. Cut a wire (the same length as the last), solder it to the first lead, shrink tube to the next lead, solder it to the next lead, and so on.
Once all of the LEDs are soldered in to the end you need to start working on the switch and battery snap.
Step 14: Glue on the Face Plate and Wire the Switch
You need to align the inner ring (that we've been wiring) to the face plate of the lamp. Make sure the hole for the switch is where you want it. Clamp things together as best you can and run some acrylic cement around on the inside of the lamp. Leave this to set up well before working on it anymore.
Screw (or attach) your switch to the lamp. The positive leads will connect to the switch (to the negative side, if your switch is labeled.) Shrink tube over the wire most of the way there. Cut a piece of the larger shrink tubing and slide it on. Then put the wire through the switch prong, twist it back on itself and solder. Slide the large shrink tubing down over this connection and shrink it.
Attach a wire to the other side of the switch the same way, and shrink it for about 5 or 6 inches. Slide on a piece of the big shrink tubing. Then twist that wire together with the positive lead from the battery snap. Solder them, then fold the solder section back toward the switch and shrink over it. This is to prevent the connection from coming undone if someone pulls on the battery. Do the same thing to connect the negatives from the LEDs to the negative on the battery and your wiring is done. Pop in a battery to check things before you close it up for good.
Step 15: Glue in the Front and Back Panels
Glue the outer ring onto the face plate, using lots of clamps and acrylic cement. Double triple check your wiring, then glue on the back panel.
Step 16: Chain Up the Cast Pieces
Chain together your cast pieces and hang them from the hooks at the top of the frame.
Slide each one (except the bottom row) onto craft wire. Make a loop on the wire, slide the piece down, then cut it off (around 3/8") and make a loop at that end. Using round nose pliers makes this easy. This turns each into a charm. Use a head pin for the bottom charm so there's no loop at the bottom.
Use jump rings to link them into vertical rows. I used one position of each alien for one row of charms, the other position for the row of charms on the other side of the LEDs. I used some short lengths of chain at the top to make sure the strands were all aligned. The orientation of the loops on each piece determines the direction it hangs. You can use a bit of super glue at the place where the loops and piece meet to keep things aligned.
Get them in some good sunlight for a while for the best glow.