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ProdMod LED Hula Hoop Assembly

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Background

The following instructions are to be used to create an LED Hula Hoop using the LED Hula Hoop Kit found on this website. The kit and instructions are designed so that you can assemble the hoop in about 2 hours using minimal tools and where soldering connections is optional. There are always more advanced ways to assemble and finish the hoop. If there are any advanced tips they will be noted throughout the page or at the bottom.

You can follow these instructions for both 3/4 inch and 1 inch thick hoops. The only difference is there is some modification recommended for the 1 inch connector as seen in step Eight.

Also your 3/4 inch kit will come with an extra strand of thin wire that you might use near the battery if the fit is too tight.

These kits do not include resistors because they are not required in this combination of LEDs and Battery.

Parts: Check your kit:

You should have one coiled up white tube
A package of parts
A coil of wire.

Inside the package of parts you should find:

7 Blue LEDs
7 Green LEDs
7 Color Changing LEDs (Or White depending on your purchase)
One Plastic Connector
One Battery with leads
One switch

Get tools:

Wire stripper
Hair Dryer
Leatherman Tool
Knife
Power Drill/screw driver with drill bits
Electrical Tape
Rope or stiff wire - 11 feet
Metal File and Coarse Sandpaper
Optional Tools: Dremel/Rotary tool

Make It:

(Reading Hint: you can skim through all the photos by clicking the first one and then using you right arrow key to advance to the next in a slide show format)

Step One: Prepare the Wire:

The coil of wire is most likely two 12 foot long wires paired together. Leave them paired for now. If you already have two separate wires, you should tape them together at one end.

Using a black marker, mark both of the wires in intervals of 6 inches apart.

Mark the wire every 6 inches - be sure to mark both sides of the wire pair.

Start from one end and work your way to the other end. You can do this by using a ruler, measuring tape, or by folding the wire every 6 inches. Make sure you mark both sides of the pair. Later you will separate these and still have to see the marks on each wire. Only make 21 marks, one for each LED. You will end up with extra length of wire at the other end. This will make it easier to fish the wire through the tube and will give plenty of slack for connecting the switch and battery.
Hold the end of the wire, the end with extra slack, and look closely at the end of your paired wire. You should see a small cut between the two wires. If you don’t see it, then use a pair of cutters to make the cut as shown in the photo.

split wires

Then you can simply take one end in each hand and pull it apart.

pulled wire

Pull it about 4 inches apart for now and label each wire using scotch tape. Label one wire as “+” and the other as “-“.

label wire

(You can also use the color coding on the wire itself, one wire has a white stripe, the other does not. But this is sometimes hard to see. Typically the white stripe is used for negative) Now go ahead and keep pulling the wire apart until you have two separate strands.

Step Two: Strip the wire:

You are going to have to strip away the plastic insulation of the wire at each of the point you marked. This exposes the copper wire that you will later attach the LEDs to in order to make you electrical connection. I highly recommend using a simple quick stripper tool to do this. Or use a standard wire stripping tool. I do NOT recommend using a knife or razor blade.
Work with one wire at a time. When you strip these areas start from one end and work your way to the other. NEVER use this tool on the same area twice, you will almost always cut the wire right off. See the video below for an example of the correct method.

In the first video I use a red wire so its easier to see.

Here is a video where I make 21 strips in about 2 minutes. Notice how I am holding the wire and where I start.

 

If you use the quick stripper you would probably get 1/8” gap each time.

eigth inch strip

This is ok if you are only going to wrap the LEDs in place and not solder, but a ¼” gap is better in general and easier for soldering.

quarter inch strip

To make the gaps bigger I recommend pulling the wire insulation apart with your hands. You may have to keep pulling each section in the same direction.

When this process is complete you should have two wires that each have insulation stripped in 21 locations about 6” apart from each other. Pair them up with each other again so that the stripped areas are next to each other as they were before you pulled the wire apart. Find the end with your positive and negative labels. Now pull the positive wire up about 1 inch so that the stripped areas are offset as seen in the photo.

Use scotch tape to fix the two wires together and strip the very ends of each wire on the side where the labels are – strip almost ½ an inch, you will use this later to connect to the battery.

wires tied and labeled

Step Three: Prepare the LEDs:

The LEDs in your kit come in different bags so that you know which ones are Blue, Green, or Color changing. These LEDS were chosen for their brightness and subsequently they also don’t have any color tint on their lens. So as you work with these LEDs you will want to keep track of which color they are. You might want to work with only one color at a time and return them to the original labeled bag when you are done. Or set them aside in different areas of your workspace or in labeled cups or trays.

Bent LED with sharp corners

 

To prepare you LEDs take the longer leg of the LED – positive leg - and bend it out to the side and up as shown in the photo. Do this carefully and slowly. Don’t bend the leg more than once in different directions, it may break off. Try to create smooth curves and avoid sharp corners. But sometimes its unavoidable. Use needle nose pliers if you have them.

(In this kit you do not need to use resistors, but if you chose to you would solder them to this longer leg that you just bent.)

Repeat this step for all of your LEDs keeping track of their colors. Perhaps you can place each color into a separate paper cup.

Step Four: Connect the LEDs:

First you’ll have to decide where you want each LED to go. The current kit supplies you with an even number of each. So you could alternate them one at a time like Blue, Green Color, Blue, Green, Color etc. Start with the end of the wire pair that you have labeled and tied together. Twist the bent leg of the LED around the exposed part of the positive wire. Notice how it wraps around the insulation as well.

twist leg of LED onto the positive rail

Then twist the straight leg of the LED around the exposed part of the negative wire. Use the extra length of the LED legs to wrap around the insulated area of the wire as shown in the photo.

Twist leg of LED onto the negative rail

Repeat this step for the remaining 20 LEDs in the color pattern you’ve chosen. Be sure that you are always connecting the bent leg to the positive wire and the straight rail to the negative wire. Otherwise the LED will not light. Use the battery to test your circuit after each connection so that you can catch a problem early.

Step Five: Testing your circuit:

You can test your circuit after each LED or every few LEDs are connected. Or you can wait until all LED connections are made. Before you connect the battery make sure that you stretch out your wire so that the LEDs are not touching each other or creating any shorts. Now connect the positive wire near the label to the positive lead of the battery. Make this a temporary connection by twisting the wire around the battery lead once or twice.

test circuit with battery

Then simply touch the negative wire to the negative lead of the battery. Your LEDs should all light up. If any LEDs are not lit, check that they are in fact making a connection to the copper wire. Then check that they have the correct polarity. The long bent led to the positive wire and straight leg to the negative wire. One common mistake is that you bent up the wrong leg when you prepared the LED. You can try removing the LED from the wires and attaching it backwards. If it lights up, then you can leave it in that position, do NOT try to bend the LED legs in a different direction, they may break.

Step Six: Fix the LEDs Tape or Solder?

If all of your LEDs lit up as expected you can now fix them in place. I have made and used LED Hoops that I simply twisted LEDs onto the wires without any tape and they worked just fine. But over time there is a chance they can come loose. So at minimum you should wrap the connections with electrical tape. Its more to keep the LED connected than it is to prevent a short. Wrap as shown below. You only need about 1 inch of tape per leg. But if you want a more solid construction you can go ahead and use a soldering iron to apply some solder to each of the twisted sections of the LEDs. Then you can still wrap each leg in electrical tape to avoid electrical shorts.

use electrical tape to insulate the LED legs

You can use white or black, they look the same in the tube when the LEDs are on.

ADVANCED TIP! - Silencing the hoop

If you are a real stickler for a silent hoop you may take this opportunity to wrap the wires in a thin layer of bubble wrap about 3 inches 2 or 2.5 inches wide and 3/16 thick. This prevents the LEDs from hitting the inside of the tube while you hoop. Which you wont notice with loud music, but some people prefer this treatment. These photos should help guide you.
PLEASE NOTE!!
Wrap it tightly so that it is not too thick for the tubing.
Be sure to face the bumpy bubbles towards the LEDs and leave the smooth surface on the outside. This makes it a bit easier to pull the wrapped wire through the tubing.
The bubble wrap technique might be too thick for the thiner 3/4 inch hoop tubing. You may want to try clear plastic saran wrap instead.

laying out a thin sheet of bubble wrap

ProdMod LED Hula Hoop Workshop 235

using electrical tape to keep it wrapped

Step Seven: Prepare the tubing

STOP!! - CLICK HERE if you want to add the rechargeable battery upgrade.

There are two ends on your tube, one will have the switch and a coupling fixed into the tube. The other is where the battery will slide into along with the looser fitting end of the coupling.

sketch of connector battery and switch wiring

Using the connector, mark the tube to indicate how far the connector will reach into the tube. This gives you an idea of where the switch can be. Give yourself another inch to give you some room.

Mark the switch location

3 inches seems to be a good place to start. Use a marker to sketch out an area to fit your switch.
NOTE!! If you want to plan ahead for the possibility that you upgrade to a rechargeable battery in the future, then you should move the switch over another inch. So you will be about 4 inches from the end. Then later you can make the hole for the DC jack between your connector and your switch.

Use a black marker to layout the size of the switch hole

There are a few ways to cut the hole for the switch. You can use a box-cutter style razor or a very sharp knife - the tube is slippery always cut away from your body!! You can use a rotary tool (dremel) with either a cutting bit or cutting disc. The switch body width is about 0.300″ so you could also use a 1/4” drill bit to make two holes into the tubing. Start with a small diameter bit and work your way up. Or you can make 4 small holes at each corner and use a knife to cut out the square.
Start with a drill to make holes for the switch

Then using a knife you can carve out the rectangular shape to fit the switch. But be very careful, the tube is very slippery, always cut away from your body. Or you might just use a dremel tool from start to finish. - Actually the dremel rotary tool is HIGHLY recommended. It worked extremely well in our LED Hoop Making Workshop and at the Maker Faire.

The final switch hole shape is carved out

The switch in this kit has flaps on either end that keep it from falling into the tube. We are going to finish this switch installation later, but for now just make sure the hole is big enough from the switch body.

The switch in this kit uses flaps to prevent it from falling in

Step Eight: Prepare the connector

This LED Hula Hoop uses a non rechargeable battery, so you are eventually going to have to open the hoop to change it. The connector for the 1 inch tube is very strong and very difficult to remove once attached. To make this possible, I highly recommend you reduce the diameter of one side of the connector. This is the side that will be closest to the battery and will need to be pulled out of the tube for battery replacement.

Use a metal file or coarse sandpaper to smooth the edges of the connector teeth.

File the connector

Sand the connector so it has a smaller diamter

As you trim the teeth edges, test the fit by pushing it into one end of your tube. You should be able to just get it in by twisting and pushing. You don’t want it too loose. And if you are measuring, the diameter should be about .830”. It’s better to be too big, then too small. You can always remove more material, but you can’t add it.

When you are done the connector looks something like this

Modified connector

You should do something similar for the 3/4 version as well.

Step Nine: Fish Wire Through:

Now you are ready to fish the LED wire through the tube. I recommend using a stiff wire. A really cheap source is from the window installation section of a hardware store. The brand I used is called OOK. Its basically 22 Gauge galvanized steel wire, it even comes with a built in cutter. I think its $3 for 100 feet.

Stiff Wire - OOK galvanized 22 guage steel wire

You’ll need about 11 feet of this stiff wire. Basically a bit more than the length of your tube. The concept is simple, send the stiff wire through the tube first so you can use it to pull your wire through the tube. The LED wire alone is probably too flimsy to push through the tube on its own.

You should have some extra slack at the end of your LED wire away from the LEDs. This is the end that will eventually be attached to the switch, jack and battery. You might have marked them “+” and “-”. Tie the stiff steel wire to that end of the wire.

Attach Stiff wire to long end of LED wire

Form a hook with one end of the stiff wire, and tie a single knot around that hook with the LED wire.

Tie a knot with the LED wire around a hook you form with the stiff steel wire

Then use the long portion of the stiff wire to wrap tightly around the LED wire. This should be tight enough so it wont come loose as you pull it through.
NOTE!! If you have wrapped the wire in plastic or bubble wrap make sure that the stiff metal wire is firmly attached to the LED wire and the plastic wrapping, not just the plastic.

wrap the stiff wire around the LED wire

To get the wire to align properly with the switch hole you will need to insert the stiff wire into the end of the tube opposite the switch.

Insert the stiff wire through the end of the tube opposite the switch

Slowly and gently pull the LED wire through the tube by pulling the stiff metal wire that you have exiting the tube near the switch. Have a friend help you straighten the hoop temporarily so that you feel the least resistance to movement. Especially if you have used plastic wrap or bubble wrap around the wire.

When you are done pulling the wire through you should see something like the photo below. Your last LED is on your right. DO NOT pull any further, that last LED might slip into the tube and drop too far, and you’ll have to start over again.

pull the wire through the tube

Now slowly pull the wire further until the last LED falls into the tube. Tape that end of the wire to the tube so that it doesnt fall in while you work on attaching your switch. Remove the stiff wire from the LED wire.

Tape end of wire to tube and remove stiff wire

Step Ten: Switch installation:

These steps are not for the rechargeble battery upgrade. If you are using the rechargeable battery option you must click here.

Using a paper clip, bend it into the shape of a hook. Reach into the tube through the switch hole and pull out one of the wires. It doesn’t matter which.

Pull switch wire through switch hole

Then cut that one single wire and strip both ends. Expose a long length of copper wire, about 1 inch.

cut the one single wire and strip the ends about 1 inch

You are only going to connect with one set of outside terminals and the one set of center terminals. Send the wire through the both holes in the switch terminals and twist them tightly as shown.

Slip one of the wires into the through hole of both of the end terminals.

Twist the long wire around the terminal and itself

Arranging the wires on opposite sides helps keep it from shorting.

Route the second wire from the other side of the switch

switch wire is wrapped

Test the circuit by connecting the exposed ends of the wire to the proper battery terminal and slide the switch lever a few times. You have a choice again here. You can leave it connected like this and wrap it in electrical tape to keep the connection and prevent shorts. You might even try covering the wire and terminals with hot glue.

tape the switch wire and terminals

Or you can solder the wires to the terminals for a more permanent connection and then wrap it with electrical tape. When your switch connection is complete you can push the wires back into the tubing and seat the switch.

push the wires into the tube and seat the switch

Then use electrical tape around the flaps to keep the switch in place.

tape the switch down using two strips of white tape.

This might also be a good time to cut off the long slide lever. WATCH YOUR EYES! Wear safety glasses. That thing shoots clear across the room at high speed when its clipped off!

cut off the switch leverSwitch lever is now more flush with the housing

Step Eleven: Install the Coupling:

Remove the string from the wire. Pass the wires that extend from the switch through the coupling.

route wires near the switch through the coupling

If you had modified one side of your coupling you would make sure that side is pointing out of the tube.

This is how your modified connector should look

Press the unmodified end of the coupling into the tube near the switch. This is probably going to be hard to do. To make it easier you should heat up that part of the white tube with a hair dryer or heat gun. The more you heat the tube the easier it will be to push teh coupling in.

press connector half way into tube

If you still have trouble pushing the coupling all the way you can try pressing it up against a hard flat surface like the floor. BUT BEFORE YOU DO THAT be sure to tuck in the wires first, otherwise you can accidentally cut them off.

tuck the wire into the connector before pressing against a flat surface

So after you tuck the wires, heat the white tube again and push it against the floor.

use a flat surface to press connector all the way

Step Twelve: Attach Battery:

Cut the negative wire about 2 inches from the connector

cut the negative battery wire about 2 inches from connector

Strip that end and wrap it around the negative lead of the battery.

wrap negative wire around negative battery leg

Then wrap the lead of the battery around the plastic part of the wire like you might have done with the LED legs.

Then wrap the lead of the battery around the plastic part of the wire.

I recommend you leave it connected like this, so that it is easier to replace. If you solder it in place you will have a harder time to replace the battery. To keep the battery from extending too far you might want to bend the battery leg again as shown

Fold over battery leg to shorten its reach

Then do the same with the other end of the battery.
NOTE:
You will want to wrap this end with electrical tape, just to make sure it doesn’t accidentally touch the LED in the tube.

repeat the same procedure for the positive battery wire

Step Thirteen: Close the hoop:

Slide the battery into the open end of the tube and push the tube onto the connector. Snip off any excess plastic on the connector if you have not already

snip off the post on the connector

Push the two ends of the tube over the connector and get them as close as you can. Use electric tape to keep the hoop securely closed.

use electrical tape to help keep the hoop together

You’re done!!

Now turn off the lights and start hooping!

Send your photos or video links to prodmod and be included in our gallery.

Final Touches

You are not really finished, are you? There is always more you can do with a DIY project. You can mod this ProdMod, in fact it is strongly encouraged.
Some suggestions:

Add gaffers tape to increase the grip.
Use sandpaper on the inner diameter to improve the grip.
Use some colorful electric tape to add some style.

Upgrades to enhance your LED hoop

- Rechargeable battery option - available for pre-order!
- Silence your hoop - simply wrap the LED wire with thin 3/16″ thick bubble wrap before sliding it into you tube. This also helps diffuse the light a bit. You might even try layers of saran wrap.

Make a request for a new upgrade - contact

Check out and add to the gallery

5 Comments so far

  1. Mundotozz on June 1st, 2008

    What an awesome fun thing! I saw this tuesday at 3 am ordered it . You got it to me on thursday afternoon. I sat down the morning before my nieces birthday party. That night she had an awesome fun toy Good product and great service.

    Shows what OPEN SOURCE mentality can achieve

    thanks

  2. Wes on July 3rd, 2008

    Simply the best instruction manual I’ve ever seen, …for any product!!!!
    anyone who can use these directions and screw the project up, should get a Darwin award.

    These days it would cost more in gas, to get the parts myself, than to just buy the kit from you!

    Thanks for putting time into this project!

  3. prodmod on July 5th, 2008

    Thanks for the positive feedback Wes. I never know if my instructions are too much are not enough. We all have different sets of skills, so it is good to know that you think I did well. So have you made yours yet? You can post some photos up on my flickr group http://www.flickr.com/groups/prodmodledhulahoop/

  4. Ansley on July 20th, 2008

    Thanks so much. This is a fantastic tutorial.

  5. Jen on August 27th, 2008

    Hey there,
    I got my kit, put it together (with minimal help from my dh lol), and took it to a class I teach at a local park. It was a great success!!! Now I need to make a few more so my kids will stop stealing mine!
    Thanks,
    Jen

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