LED Throwies

Step 1 Materials List

LED throwies consist of only a few inexpensive parts and can be made for ~$1.00 per Throwie. You can reference the parts list below or download the attached spreadsheet for more info on parts, part's numbers, vendors and application notes.

Part: 10mm Diffused LED
Vendor: HB Electronic Components
Average cost: $0.20 avg per LED
Notes: Cost reductions for larger quantities. Comes in red, blue, amber, white in both diffused and clear. Diffused works better than water clear for the Throwie application. HB has even created a Throwies packs page with deals on 10mm LEDs and lithium batteries!

Part: CR2032 3V Lithium Batteries
Vendor: CheapBatteries.com
Cost: $0.25 per battery
Notes: Cost reductions for larger quantities. With the 2032 Lithium batter, depending on the weather and the LED color, your Throwie should last around 1 -2 weeks.

Part: 1-inch wide Strapping Tape
Vendor: Your local hardware store
Cost: $2.00 for one roll
Notes: One roll will make many throwies

Part: 1/2" Dia x 1/8" Thick NdFeB Disc Magnet, Ni-Cu-Ni plated
Vendor:Amazing Magnets
Cost: $13.00 per 25 magnets
Notes: Cost reductions for larger quantities

Part: Conductive Epoxy
Vendor: Newark In One
Cost: $32.00
Notes: The epoxy is optional.

Comments

[makerboy112]

You can buy ten rare earth magnets at Harbor Freight for 2 bucks

[jhames]

For someone that would prefer not to shop online what electronic stores carry LEDs? Lives in the US.

[lgraham938]

 I got mine at Radio Shack

[Glockenator]

radio shack would be the best. and it was the best in canada til they closed every canadian store

[sammyd901]

In my experience radio shack overcharges for everything. I only stop in if i need something fast that i cant find online.

[zack247]

yeah they replaced it with "the source", even though, in the store closest to me, they dont know anything about anything, and they have hardly any electronics parts, they have just about a wall thats 6' by 6', and most of the things are protoboards and project boxes, and the only chip they have is the 555, not too much you can do with that.

[killler64]

radio shack is realy expensive tho

[philipwoodall]

 actually they just changed the name to the source, radio shack still owns them.

[sawatzky]

??? RadioShack Canada was own by Tandy Corp. And Licensed the RadioShack name. CircuitCity Bought Tandy, and RadioShack refused to renew the license to it's competitor, CircuitCity so CircuitCity just called the old Canadian RadioShacks "The Source from Circuit City". So are you saying that RadioShack bought CircuitCity???

[Rane]

Radio Shack usually has some stuff.

[Tobz1122]

what about England?

[nadina]

 You can get this in Europa at www.ozhobbies.eu/.
The cube throwies are pretty cool.

[anonymouse197]

Maplin

[Minifig666]

 Or Rapid Electronics (Google It)
Maplin is sometimes more expensive but the convenience of its store's makes it better.

[Rane]

I dunno, never been there. Lol.

[llamma1010]

umm i think you should update the price on the epoxy it now costs 59.97!!!!!!!!!!!!!!!!!

[M4industries]

 The led's are about $0.16, but you have to order $25 worth!

$25/0.16= 156.25 (Rounded to 157) LEDs!

I don't need 157 LED throwies.

[mechanismango]

so when it says its a 1.8v - 2.4v LED will it still work with a 3v battery or what? Will it just burnout faster?

and of http://www.kjmagnetics.com/products.asp?cat=17 or http://www.gaussboys.com/magnets/discs/ which magnet is best? a 10mm by 2mm?

[scld]

That voltage rating is for the LED itself. Basically, when it is turned on, there will be 1.8-2.4V across it. So, you need at least 2.4V for the LED to turn on (preferably a little more).

However, you usually don't want to have just an LED and a battery. You want to have a resistor in front of it, too (It's OK in this case because you're using a 3V battery with a 3V diode, so it's pretty close).

In your case, I would put a 30 Ohm resistor in series with the diode. The diode will drop 2.4V and the resistor will drop the other 0.6V. The resistor will cause about 20mA of current to flow through the diode, which should be enough to turn it on!

[imarzouka]

scld is right.. you will need to add a resistor in this case so that the LED won't burnout.

Just enter your led specs and battery voltage here: http://ledcalculator.net and it will tell you which resistor to use.

[meghann]

So are the magnets necessary if I'm just wanting to add LEDs to a costume (I'm new to this...so the lights will glow, without the magnet?)

[jensenks]

Oh, yeah!  The magnet is solely for sticking.  We hooked up 6 LEDS to one battery today and they worked great.  We're going to extend them with wires so they won't be bunched up for a model we're putting together.  One thought on your end - would it help to use white duct tape (better than your standard siver stuff) to fasten your lights to the costume.  Good luck with your project!

[bassclarinet23]

Magnets are not necessary if you don't want it to stick to something. You only need an LED and a power source, though a switch would be useful if you want to be able to use the costume again (long term), plus it saves battery.

[firezone]

and you dont have to do the same as here, you could wire up a long line or web of led's and power it with a slightly bigger battery, that would take a lot less money and time 

[godofal]

yes, leds only need power to light up ;)

[bassclarinet23]

What are these "rare earth magnet" things? I've seen them onmany projects, nut how do they differ from magnets, let's say, from aMagnetix toy. (I don't mean to sound rude, I'm just curious.)

[paperclip32]

 they are made from neyodinium(?) and are extremely strong.

[bassclarinet23]

Okay, thanks.

[Yerboogieman]

Strength, metals they are made with, tons of things. Crack open an oldhard drive.

[bassclarinet23]

Okay, thanks for the information.

[REA]

the magnets are alot cheaper herehere

[xfnord]

Thats more expensive the the price for a complete led throwie. check this out[]

[REA]

>Jun 20, 2008.

it was cheeper a year ago when i posted...

[xfnord]

hmm - right you're message is one year old :) did not realized that

[chemfiend4568]

check out their surplus magnets. 2 zd1 or 1 zd2 magnet would do the job, and they're pretty dang cheap in bulk

[Geo242]

The link you posted now shows magnets between $.50 and $.60 each for orders less than 100, but it may have been cheaper when you posted it.

[REA]

oh wow! it was about $0.19 per magnet when i had posted that.

[Redgerr]

prices change ;) wish you ordered 100000 of them now? :P

[REA]

yes... ='(

[laurajean00]

also wondering if anyone could guess at how many throwies i would need to put in a lantern for an outdoor wedding reception?