Intro: Soft Circuit Blinky LED "robot" Ornament
Learn how to make a quick and easy robot ornament complete with blinky torso panel! This is a very simple circuit and will require beginner sewing skills and no electronics experience.
Step 1: Gather Materials and Tools
You will need the following:
-felt (I went ahead and cut mine in the shape of a robot for this picture)
-Shiny translucent silver fabric
-Sewable battery holder
- 3v coin cell battery to fit holder (these are 2016's but several sizes actually fit)
-needles that fit through the holes in the Sewable battery holder
-Googly eyes (or other embellishments for eyes)
-blinky LED (https:// www.amazon.com/dp/B006LUZLNY/ref=cm_sw_r_other_awd_JTDzwbJMJD5WG)
-string/ribbon to hang ornament from tree
-needle threader (optional)
-resistor is not needed if using the LEDS I used, however, if your LEDS are different, you may have to work a resistor into the circuit
-marker (or fabric paint) for adding details to your robot
Step 2: Preparation
First, we will do a few quick things to prepare. After the first step, Which order you do these in is of no consequence.
-cut your felt into the shape you want your robot to be. ***Make sure to measure the width of the battery holder and make your robots legs slightly wider than the battery holder.***
-cut your silver fabric to about the same size as the robot's torso. You want it to be no more than 2-3 mm smaller than the felt to make sure that you have enough fabric to adequately cover the LED.
-take your LED and identify which leg is longer. Mark that leg well with the red sharpie. This is the positive leg of your LED
-identify which side of your battery holder is positive and mark the hole with the red sharpie.
-poke a medium sized hole in the top of the robot's head using whatever's handy. Be very careful if using scissors because one slip could mean too large a hole or even a destroyed head. This hole will be for hanging the ornament on the tree.
-If you are not familiar with soft circuitry or E-textiles, I would suggest you look at these instructables on sewing a circuit:
In fact, there is lots of good information in the e-textiles section of this site https://m.instructables.com/id/How-To-videos-for-eTextiles-soft-circuits-and-we/
Step 3: Adding the LED
Using your needle, poke two small holes on the robot's body right below the center of the neck. Use the led legs to determine how far apart these holes should be. Then place the LED leads in these holes and gently push the LED as flush as possible to the robot body.
Once you have done that, bend the led over so one side is flat to the body.
Once the LED is in place, carefully flip the robot over so as not to let the LED fall out. Bend the LED leads into loops.
Step 4: Sewing the Circuit
Go ahead and thread your needle with conductive thread. I use a double thread technique. You can use single if you're more comfortable with that, too. Either way, make sure you have a really good knot at the end (I tied at least two on top of each other).
Place your battery holder on the back of the robot (same side as the led legs/loops). ***The red side of the battery holder should be on the same side as the red led lead***. This helps make sure that the power flows correctly and the LED will light up.
Stick the threaded needle through the back of the robot and into the red hole of the battery holder. Sew up through the fabric on the outside of the holder. Sew back down in the middle of the hole and repeat several times. You want to make sure the conductive thread is making good contact with the lead on the holder. This also helps make sure the battery holder is securely held in place.
Now that one side of the battery holder is secure, sew up to the red loop of the LED using a running stitch.
Once you get to the loop, put your needle through the middle of the LED as in the picture. Then use the needle to tightly wrap the thread around the inside of the loop. Make sure to keep the thread tight around the LED lead. Once you have wrapped it around several times, stick your needle back in and go back over the last couple of stitches you made for the led. You want your thread to be exactly over these stitches in exactly the same direction. Then tie the thread off with a good knot (I did at least two on top of each other). Cut the thread short so it can't touch the other side of the circuit but leave enough that the knot can't easily untie itself.
Thread your needle again and repeat this step for the other side. Make sure that when you stitch, the two sides are not touching. (If you need a resistor, make sure you work it in to your second side).
When done sewing. Cut all knots to a short length and then put a dot of fabric glue on all four of them. This will help keep the knots from fraying, which can cause shorts.
Step 5: Testing the Circuit
Now put the battery in and test your circuit. If the LED on the front of the robot lights up, you're good to go.
If not, check to be sure the battery is in correctly, try another battery, etc.
If the problem is not the battery, check to be sure you don't have any stray stitches that could cause a short or any stray threads looped around LED legs or anything like that (conductive thread can be sneaky sometimes). If you don't see any obvious problems, try cleaning the area around your circuit with masking tape. This will help get rid of any tiny "whiskers" of thread that could be hanging around the fabric and causing shorts.
If it still doesn't light up, you should probably get out a multimeter and troubleshoot the circuit. Here is an instructable that can help you with that
Step 6: Gluing Stuff
Once your circuit is sewn and working, take the battery out (for now). Flip the robot back over. Put a line of fabric glue just above the LED leads all the way across the top of the robot's torso. Be careful not to touch the glue with the leads as this could potentially cause a short (some glue does have a small amount of electrical conductivity even when dry).
Once your glue is in place, place the correct edge of the pre-cut the silver fabric on top of the glue and press down. Glue the other edges down as well and press. The silver fabric should now cover the LED. The fabric will bubble up slightly because of the LED and this may cause some wrinkles on the edges of the Silver fabric. Your edges will probably not be perfectly straight and this is fine. The fabric needs to be able to form itself in a shape that accommodates the LED.
Once your torso panel is glued and secure, glue your eyes. If your googly eyes are self-adhesive like all of mine are, you will still need to use fabric glue, however, make sure you peel the protective backing off first.
Step 7: Finishing Touches
After the glue dries, add the finishing touches to your robot with a marker or fabric paint. I added a nose and angular mouth in the face. Then I added lines on the lower section to give him some separation of the legs. Then I added some dots on the chest panel to make it look like buttons.
However, don't feel bound by my suggestions, decorate your robot friend in whatever way you like best!
Step 8: Hang Him on the Tree
Thread your ribbon or cord through the hole you punched in the top of the robot's head in the "preparations" step.
Tie a loop whichever way makes you happy.
Put the battery back in the battery holder on the back of the robot. Now hang him on the tree for everyone to see! Yay robot!