Introduction: LED Jellies

About: I'm a digital artist/crafter/maker who likes electronics and sewing. I used to run the blog Soft Circuit Saturdays, which is now part of my site GellaCraft - dedicated to techy crafts, costuming, and art.

Who doesn't love LED throwies? And who can resist adorable sea creatures? I've combined the two to create LED Jellies!

This Instructable will show you how to make a jellyfish shaped casing for LED Throwies that you can stick to any metal surface. The Throwies are easily removable so you can 'refill' the Jelly and use it over and over.

*They might be cute, but remember to keep them far away from anything that could be damaged by magnets*

Step 1: Materials

To make a single Jelly you will need...


* Quilt Batting - you can find this by the yard or buy a roll at the fabric store. I used 1/4" low-loft polyester batting.

* Sheer Fabric - I'm using bubble organza which is nice to work with and doesn't fray too much. You could also use tulle or any fabric with some translucency.

* Ribbon - choose a fun ribbon for the tentacles. I found some funky stuff in the Walmart clearance aisle that had some sparkly & tulle strips woven in.

* Plastic Bubble - I don't know what the technical term is, I think it is 'toy capsule'. You get them from the toy dispensers in supermarkets and arcades, and could probably order in bulk online.

* (2) 3V Lithium Coin Cell Batteries - the LED Throwie Instructable recommends CR2032, but I am using CR1616 because they are nice and tiny.

* (3) Rare-Earth Magnets - I found some 'super strong' magnets at the craft store.

* (2) 10mm Diffused LEDs - If you don't have/can't find anything but clear, then check out this Instructable that shows you how to sand the surface.


* Pliers

* Hot Glue Gun

* Scissors

* Needle/Pins

* Thread (match color to your fabric)

* Marker

* Tape - strapping tape is best, I only had packing tape when making this.

Step 2: Cut Out Pieces

Time to make the Jelly's body!

*I am using plastic bubbles that are about 2" in diameter. These pattern pieces/instructions are for this size, but if you have a bigger/smaller bubble you can adjust as needed. I've attached a pdf template if you'd like to use it.*

Cut a circle of batting ~5.5" in diameter.

Cut 2 circles of your fabric ~8" in diameter.

Cut some pieces of ribbon for your 'tentacles'. I made mine ~6" long. The number will depend on your personal tastes and the size of the plastic bubble. This example has about 9 tentacles.

Step 3: Attach Tentacles

Take your plastic bubble and glue your ribbon tentacles to the clear top section. Make sure not to glue the top and bottom of the bubble together - you'll want to be able to open it up and place your Throwie in later on. I drew a line to help keep my tentacles even/out of the way.

Step 4: Sew and Glue Body

Place your batting, centered, on top of the 2 pieces of fabric. Fold the fabric over the batting and pin.

With a needle and thread, sew through your layers of fabric and batting ~ 1/4" from the edge of your overlap. Be careful not to do any back stitching. When you are finished, pull the thread to gather the fabric and make a scrunchy jellyfish shape (do not knot/tie off just yet).

Place your Jelly Body over the top of the plastic bubble. If you need to, adjust the gather so that it is snug and tie a knot to finish it. Glue the fabric to the plastic bubble, covering the tops of the ribbon tentacles. Again, make sure not to overlap the bottom - leave ~1/4" of space to work with.

Congratulations, your Jelly is almost finished! Now on to the Throwies...

Step 5: Make Throwies

I made these Throwies a little different than the original instructions...

Take your LEDs and use a pair of pliers to bend the leads at right angles, with the anode (longer lead) on 'top.' This will give you more space inside the bubble and also point the light upwards. Leave ~1/8" space between the leads, just enough to slide the battery between them. Add a drop of hot glue between/around the leads before the bend to make sure they don't accidentally touch.

Step A: Slide a LED onto one of your batteries (if the leads extend past the battery, shorten them with some wire cutters). Wrap it up in tape (same as original Throwie tutorial), making sure that it is nice and secure and doesn't flicker.

Place one of your magnets on top (positive side) and wrap up some more so it doesn't slide.

Repeat Step A with your second LED, and place it on top of the magnet. I oriented my LEDs opposite each other to cast more light throughout the Jelly. Place a second magnet on top of that and wrap up with more tape. *You don't really need this other magnet, but adds a little extra holding power.*

Step 6: Assemble the Jelly!

Your final magnet will attach to the bottom of the plastic bubble and hold your Throwie in place. Make sure it is oriented the right way before gluing by testing it out on the bottom of the 'Throwie' pile.

Hot glue the magnet to the center of the inside of the plastic bubble, place your Throwie on top. Then just snap the top of the bubble back on and enjoy!

At this point you can add some finishing touches, maybe some embroidery or a happy face. I separated the strands of my ribbon tentacles to get more of the wispy/stringy look. You can also try out different combinations of LED colors and plastic bubbles.

*Although these are Throwies, the plastic bubbles are pretty brittle. I don't recommend tossing them at things, I had a few bounce off surfaces and break when the magnet didn't catch.*