Introduction: Keith-Ki-Domo-kun, Instructables' Keith-Kid Domo-kun
The construction is similar to the Ro-Domo-Kun Instructables Robot Domo-Kun. Present day Domos may have evolved from this prehistoric reptilian type of Domo. Environmental changes through the ages seem to have made obsolete the scalely armor-like skin and primitive behavior of flashing its eyes and mouth when sensing danger based on instinct. The tail appendage also seems to serve no other purpose than taking a swipe at tall buildings in its way..
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Step 1: Dig for Materials...
For this project you will need:
You can select any color or pattern of your choice to make the Domo. I just happen to have some green and Instructables orange material to use. You can make this in team colors, unfortunately it seems this turned out like a Miami Dolphins football team mascot.
~~pelts~~ Material for the covering of the Domo
a block of foam, sponge or even cardboard to form the core of the body.
scrap bits of felt or material for the mouthpiece, teeth, footpads
polyester fiberfill or batting
pieces of stiff bendable wire for the appendages
a cheapo LED bicycle safety flasher unit
some electronic soldering/desoldering skillz
some sewing skills - this can all be done by hand with needle and thread but it will be a lot easier with a sewing machine.
Step 2: Light It Up...
For the cool blinking LED portion of this project we will reuse the technology from of the Adrian Monk Disneytopian Blinking Hand of Righteousness Turn Signal Glove.
These flasher units are activated by a push button switch which can toggle the pattern that the LEDs flash. Constant on, blink. slow blink, cascade left, cascade right, chase back and forth, and off.
It is amazing that they have these LED clip-on safety lights at the Dollar store. Each flasher unit is a self-contained battery pack, controller circuit, 5 bright LEDs, and an optic bezel. It runs on two "AA" size batteries.
We need to disassemble the unit in order to:
extend the LEDs from the circuit board so we can position two LEDs for the eyes,
extend the battery pack so we can place it better,
and extend the switch so we can place that in the end of the Domo's hand.
Step 3: Soldering Microelectronics Is Fun...
It would be a simple task to extend the connection points where each component is soldered in by adding a jumper wire.
Desolder the two LEDs, use a white-out correction pen to indicate the correct polarity or which hole they came out of and resolder the corresponding wire.
Add a new momentary switch to replace the flexible push-button switch built into the case.
Add a cable to extend the battery pack to the circuit board.
This seemed easy until:
The circuit board is a product of mass production where the cheapest and lowest quality materials were used.
IT GOT UGLY...
I had to drill a tiny hole in the circuit board pads in order to get the wires to hang on.
In the process of desoldering the LEDs, you are left with extremely tiny leads which are harder to resolder. I found that by just tinning the wire end and just touching it to the lead attached it. Any attempt to blob on any more solder would just desolder it. It doesn't help that the soldering iron tip is larger than the gap between the leads so you could accidentally desolder the other lead. I had melted the casing to try to get a lead soldered on but I think I destroyed the LED.
In desoldering the LEDs and using a solder sucker, the heat seems to have delaminated the trace. It seems that the traces may have only be printed on and not a true circuit board etch. I had to try to attach micro jumpers to recreate the traces.
After I completed all of the extentions, I ended up with an unreliable circuit for some reason. I went back in to change out the switch but discovered after a few hairline cracks that started to delaminate the trace just by wiggling the wire. I had one trace that broke up so close to the embedded IC that I didn't really know if there was a connection.
And of course, I tried to scrape off the protective laquer layer with a razor blade to expose the trace so solder would stick to it
And like Goodhart, I think I need new glasses when working with these tiny things.
WHAT DID I LEARN?
You need lots of tools to do simple soldering.
Do not attempt microsurgery without good lighting, steady hands, and good visibility. I had actually given up a day after I tried all sorts of things to salvage the original circuit board. The next day I had bought some spare LEDs, the third-hand magnifier thingy, and a few spare flasher units.
The magnifying glass is held too close to the work and you cannot manipulate the soldering iron under it. I did not have one before and trying to clamp the circuit board with pliers and tape the piece steady ended up in frustration. Also, I've sucked up way too much of the toxic soldering fumes and felt the heat by being too close to the work.
Also not a good idea to hot glue anything to hold it in place if it is near a soldering point. Chances are you will need to resolder around it but will need to remove the hotglue. And use good electrical tape if needed, stuff that is flexible and sticks.
I finally took a look at the layout and figured I could jump the wires to different and bigger pads along the traces so the soldering would be more reliable. So, after experimenting on two, the third circuit board was wired up flawlessly.
Step 4: Blockhead
Get a piece of foam that is about the size of an index card, 3x5 inches or a regular size sponge.
With a marker sketch out how your Domo will look.
The mouth takes up the upper quarter from the middle line.
Take one piece of wire and punch it through the foam to form the arms. Curl up the ends.
Take another piece of wire and bend it in a "U" shape. Like a big fork, push it down through the back at an angle so the ends exit out of the bottom to form the legs. Bend back the ends to form stubby leg forms.
Place the flashing unit on the foam block and secure the wires by cutting slits in the foam to embed the wires. Tape in place. Position the switch at the end of the arm and wind up any excess wire around the arm. Hang the battery pack off of the rear leg loop.
Test to see if your flasher unit still works.
Step 5: It's Nekkid...the Tail End.
Time to make the emperor some new clothes...
On a double layer of material, place the body form on the fabric and trace the outline. One will be the front piece and the other the back.
From a smaller scrap piece, assemble the tail.
Cut out from felt a pair of serrated dorsal tips set (somebody will correct me on what these are...) that will run along the top of the tail.
Sew it at an angle lengthwise to the top piece of the cloth.
Fold the piece in half lengthwise to cover the dorsal tips. Now flip it over and sew again following the first seam that was sewn attaching the dorsal tips. Sew it down to a point tapering the tail.
You can now flip the "cone" inside out so that you have the dorsal tips encased in a nice finished seam. Use a pencil to help push everything out when you turn the assembly.
From the outline of the Domo's back, approximate where the tail should be attached.
Cut a small hole and fit the tail through. Enlarge as necessary to get a smooth fit around the tail.
Sew a seam to attach the tail to the back. Remember to sew on the "inside" so you have the tail sticking out on the "finished" side.
Step 6: Check Out the Mouth on This One...
To create the big mouth, take a piece of material a little bigger that the size of the mouth sketched out on the foam body form.
Cut out two rows of teeth from white felt.
Sew the rows of teeth on to the mouth material.
On the front piece of body material, cut out a hole the size of the mouth. You can make two diagonal cuts across the rectangular opening.
On the inside, fold the opening flap back and sew it to the mouth making sure that it stays aligned.
You may need to go around once more and tidy up the seams at the corners of the mouth.
Step 7: Body Glove...
With the finished sides of the front and back pieces put together, sew a top seam to join them together.
Continue sewing the outline around the arms and straight down to form the outer side of the leg.
Trim away the excess material
Test fit the body form.
Mark where the feet will end and trim any excess.
Cut a small vertical slit to separate the bottom into two leg parts.
Sew a foot pad on the end of each foot. Just attach on three sides gathering up the fabric. Again, remember to do the seam on the "inside" so the finished seam will show when it is turned out.
Step 8: Time to Close It Up...
We are now ready to stuff the Domo.
Turn everything inside out.
Stuff the tail with fiberfill.
Wrap some fiberfill around the arms. Place some padding on the back.
Like putting on a T-shirt, raise the arms pointed up and guide into the armholes.
Work the rest of the foam body form into its shell.
Wrap some fiberfill around the legs. Adjust fill or padding around any of the other parts of the Domo.
With hand sewing, it is easier to connect the crotch point first to gather the front and back fabric at a central point. Folding the raw edges together, stitch and sew to close up the rest of the inseam to the footpad.
You may also want to put a stitch in to tie the tail closer to its bottom if it sticks out too much.
Final details are to adjust the placement of the LEDs.
For the eyes, I marked around the LEDs with a magic marker and went around it with a ring of hot glue. This serves to reinforce the fabric when I make a hole for the LED to peep out.
Fluff up the dorsal tips on the tail and separate the two sets.
Oops, I didn't think about needing to change the batteries. A flap with velcro or zipper would allow access to the battery compartment. Oh well, these are LEDs so it should last long enough before they need to be changed.
Hola! Now go out and have a Keith-Ki-Domo day!
Participated in the
Get the LED Out! Contest