Just in time for the holiday season! Speakers of your head are the perfect gift for mom.
This tutorial illustrates how to create cardboard speakers of your head.
-an iPad with Autodesk 123D Catch software to scan the image into CAD (free download)
*you may use a digital camera & Autodesk 123D Catch for online instead
-Autodesk MeshMixer software to massage & patch up the CAD surfaces (free download)
-optional Rhino CAD software for additional patching & refinements (free evaluation download)
-Autodesk 123D Make software to slice the CAD into sheets for laser cutting (free download)
-an Epilog laser cutter
-corrugated cardboard (36 sheets of 3/16" thick 36"x24")
-Sobo craft glue (available at craft & art stores)
-OrigAudio speakers ($16.00)
-portable power drill with 1/4" bit
-1/4" wood dowel or chop stick
-wire or straightened coat hanger
-a buddy to assist you with your 123D Catch
Step 1: 123D Catch your head
Using the iPad (or digital camera) open the Autodesk 123D Catch app. Have a buddy take photos of your head. I decided to house the speaker inside of my mouth, so I held my mouth open for the catch. Your photographer should start at a low angle & progressively increase the height of the camera. They should move around your head in about 15-20 degree increments for each photo. Use the maximum of the 30 allotted photos for a more accurate catch. Hold your pose as still as possible for the best results.
Step 2: Process the catch
Process your catch through the 123D Catch iPad software or website.
The first catch I did successfully captured my front, but as you can see in the second image my back is missing a large surface.
I did a second catch in hope of better success. The third & forth images are the results of this second attempt. For some unknown reason the catch was processed upside down, but that doesn't affect anything. The second catch captured my back much better, but kind of warped my face.
Step 3: Digital surgery in MeshMixer
Using MeshMixer, I decided to do some digital surgery & use the face geometry from my first catch combined with the body of my second catch. I copied both models a couple of times for reference & just in case I deleted too many surfaces, I could use an original one. Use the select surface & delete tools to cut out the face area on the body you want to use. Do the opposite with the other model & just keep the face. Use the move tool to position the face on the body.
Step 4: Patch holes in Rhino
I found it easier to patch surface holes in Rhino than MeshMixer. The "Fill Mesh Holes" tool in Rhino worked quite well. Once the gap around the face was filled, I created a box used the "Boolean Difference" tool to cut my torso for a flat surface for it to stand on. I then created a cylinder & "Boolean Difference" again to cut out a hole in my mouth for the speaker.
Lesson learned: If your model has a cylindrical hole with critical dimensions (such as the hole for the speaker) & stacking layers parallel to the cylinder in 123D Make (like this tutorial), the hole will be too small. See Image 5 (pink line represents resulting hole for speaker). I found this out while I was assembling the layers & ended up having to cut out space for the speaker with an X-Acto. I tried exporting the sliced model from 123D Make into Rhino & then cut the speaker hole, but the geometry became a bit convoluted when imported again in 123D Make. Thus no real solution as of now.
Step 5: Slice geometry in 123D Make
Export your final patched up model as an OBJ out of Rhino or MeshMixer. Open 123D Make & import the file. Choose "Stacked Slices" under the Construction Technique. Type in the dimensions of the laser cutter you are using. The bed size of the one I used is 18"x24". I left the default thickness at 0.1700" & kerf at 0.010". Select "Get Plans" & the software automatically slices, lays out & numbers all of the parts for your model.
This particular size of model requires 18 sheets of cardboard resulting in 93 parts.
Step 6: Laser cuttin'
Since the laser cutter bed I used is 18"x24", I cut my 36"x24" sheets of card board in halves to fit. Open your PDF files in Illustrator. I changed all my line stroke dimensions to 0.001". Follow the guide for your laser cutter for the correct settings to cut cardboard. The process of cutting out all of the parts for one head took about 90 minutes.
Step 7: Disassemble the speakers
The OrigAudio speakers I used had to be stripped from their cardboard & plastic housing. I used a metal ruler to pop the plastic rings off. You can purchase speakers & wire through DigiKey as well.
Step 8: Glue the layers
All of your parts should be etched with a numbered. Part #1 is the bottom layer. Some of the layers have etched outlines of the layer which lays on top, but most do not. It helps to have the 123D Make model on screen for reference. I tried to center each layer by eye. The first head I glued up ended up leaning a bit more forward than the digital model.
I started using Elmers glue, but it was taking awhile to set & I had difficulty adhering layers that were slightly bowed. I switched to the Sobo craft glue which worked much better.
Step 9: Route the audio wire
Once you have glued layers to about where the mouth is, you'll want to drill a hole to route the speaker wire to the bottom. Use a 1/4" wood drill bit & a power drill. Drill down in to the cardboard layers as far as the drill with allow. I used a wood chopstick & a hammer to finish the hole to the bottom layer. You need to cut the speaker wire from the speakers with an X-Acto at the solder joints on the speakers. Before you cut the wire, mark which wire is attached to which contact with a marker or tape. Tape the end of the speaker wire to a wire coat hanger or heavy gauge wire & thread the wire through the hole. I cut a narrow channel in the bottom & top layers so the wire will lay flat in the cardboard.
Step 10: Cut out a larger space for the speaker
As I mentioned in Step #4, 123D Make does not do well with critical dimensions. You'll need to cut material out where the speaker is going to be housed. Don't cut out too much, your speaker will not fit snug. Measure the driver size & cut layer by layer. Be aware of the speaker wire while cutting. Glue up the remainder top of the head, but don't attach it to the body yet. You need to keep the bodies separate so you can accurately cut out the speaker hole. Once the speaker fits in the mouth, glue both halves together.
Step 11: Solder wires to speakers
Make sure the speaker fits snug in the mouth.
Now repeat for the other speaker!
Using a soldering iron, solder the wires back to the speakers. Test that speakers are in working order by plugging the jack into a iPod or computer.
Step 12: Admire at how great you look & sound as a speaker
Plug in your music source & crank it up.
Don't mind the strange looks from your classmates or coworkers, they're just jealous.