NO Led Experience- would love some help for wedding...

[MissPaqman]

Hello,
I am looking to use LEDS to light up some paper lanterns for a wedding. I was planning on using the LED throwie technique, with the coin battery (the type in a keyfob). I have found one that I think would work, but I don't understand brightness..... the mcd just does not make sense to me. Can someone tell me if this would be bright enough to light up a paper Chinese lantern? or how many I would need?
Here are the specifications:

​

• Emitted Colour : White​
• Size: 5mm​
• Lens Color : Water Clear​
• Forward Voltage (V) : 3.0-3.2V​
• Current: 20MA​
• View Angle: About 120 degree.​
• Luminous Intensity: 1300~1500mcd​
• Life Rating : 20,000 Hours​

I like them because they have the wide angle. I purchased some 10mm super-bright cool white LED's previously with 1200mcd (is that right?) previously that I did not realize were diffused and their angle was less than 20*. I did cut the top off to make a wider beam, but it still is not very "bright"...

Is there a way to make them brighter- I.E. using a bigger battery? If so, is there a "coin" battery that is strong enough to make them brighter?

Thank you for any help.
M

 

[CrufflerSteve]

I think these are too dim. At least they are wide angle. The 5mm super bright LED's that toast your eyes have mcd ratings of 4000 to 12,000. I don't think overdriving them will help. They might burn out before the wedding is over.

Can you put 3 or 4 together? It's easy to keep track since the longer lead is positive. You don't need to light up the room, just the lantern. LEDs do well with a resistor to regulate the voltage. here's a useful calculator: http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator

Steve

 

[MissPaqman]

Hi Steve,
Thank you for the response! I found some 5mm that are wide angle at 20,000mcd and decided to purchase those. I did try, initially, to put 4 of my original LEDs together, but it still was not very bright.
I will try these and see if they work. They "appear" to be very bright, and are a warm white, so we shall see.
Thank you, again, for your help!
M

Here are their spec's in case you were wondering...
Size (mm) : 5mm
Lens Color : Water Clear
Foward Voltage: 3 - 3.2V
Reverse Current (uA) : <=30
Life Rating : 100,000 Hours
Viewing Angle : 180 Degrees
Absolute Maximum Ratings (Ta=25°C)
Max Power Dissipation : 80mw
Max Continuous Forward Current : 24mA
Max Peak Forward Current : 75mA
Reverse Voltage : 5~6V
Lead Soldering Temperature : 240°C (<5Sec)
Operating Temperature Range : -25°C ~ +85°C
Preservative Temperature Range : -30°C ~ +100°C

 

[Linger]

you're using out-dated inefficient technology that will never be very bright. The mcd ratings are just advertising, it may not relate to actual performance.
If you want a lantern that will be brighter than the full moon, maybe consider 'power leds' like Seoul ssc p4, Cree xre. (the little 5mm are like steam powered trains - ancient, in-efficient). The power leds (e.g. ssc p4, cree xpe Q2) are rated in 'lumen' or 'watts.' I don't even know what the mcd scale is supposed represent. You could find some old stock that are a buck or two a piece. They could work out cheaper by the time you put 4 or 8 of the little 5mm's together.

 

[Foxx510]

This is all very dependent on the size of the paper lanterns also, which we don't know. A decent wide angle 5mm led will be bright enough to make a 3 inch lantern visible, but it won't be lighting anything up around it much at all. A bigger lantern will probably need more light. As to your question about using a bigger battery, the brightness is related to the current drawn by the led, and the coin batteries will generally only just supply the max 20ma, which is why they can be used without a resistor. Normally, with any other battery you need to do a calculation and add a resistor based on your battery voltage, led forward voltage and desired foward current.

 

[qwertyydude]

Sounds like with all the custom work and buying retail you end up spending quite a bit. I know making a throwy with decent life by running lithiums can get pretty pricey. Then there's all the labor involved.

How many lanterns do you need to make? Because I'd say get a bunch of these and stick some transulecent water bottle caps on top as a diffuser, or heck just remove the reflector and bezel and call it a day. 8 hour run time and I know no throwy is outputting 30 lumens. Plus you could reuse them or give them away or sell them if you want after.

http://www.dealextreme.com/details.dx/sku.33543

Button batteries alone can cost more than $2 a piece so sticking with a commonly available AA means you get good life, easy battery availability, and a cheap flashlight instead of a lot of work for a disposable light.

 

[deadrx7conv]

Have you tried chemical glow sticks?

Don't rule out the $1 key chain led lights. They come with batteries already and provide decent light.

So, how big is the lantern and how bright do you need it to be?

 

[FroggyTaco]

Sounds like with all the custom work and buying retail you end up spending quite a bit. I know making a throwy with decent life by running lithiums can get pretty pricey. Then there's all the labor involved.

How many lanterns do you need to make? Because I'd say get a bunch of these and stick some transulecent water bottle caps on top as a diffuser, or heck just remove the reflector and bezel and call it a day. 8 hour run time and I know no throwy is outputting 30 lumens. Plus you could reuse them or give them away or sell them if you want after.

http://www.dealextreme.com/details.dx/sku.33543

Button batteries alone can cost more than $2 a piece so sticking with a commonly available AA means you get good life, easy battery availability, and a cheap flashlight instead of a lot of work for a disposable light.

Battery Junction sells button/coin cells for .29 each fyi.

 

[kutop]

you can buy 1W high power LED, they are enough bright

 

[MissPaqman]

Wow! Thanks for all the responses!
The paper lanterns are 8-10" and I want them to glow, they would not be the primary source of light... I like the glow these put out- but again, they aren't the primary source of light.

My lanterns are a little smaller than the lanterns picture- I think those are 12".
Otherwise instead of a paper lantern my other option is a glass tea lantern

which I can "frost" with spray paint.... I just want to create a nice- glowing atmosphere, kind of romantic?

Sorry for all the ambiguity! If there are any more questions let me know..

I noted above that I found some LED 20Kmcd that had a wide angle 180* online- if I get those LED ($30 with s/h) and use the batteries I bought on Ebay my total per LED light is still less than $.50.....

I can buy 100 paper lanterns or I have 25 of the glass tea lanterns.
So I can bulk up the tea lanterns or I can buy less paper lanterns and bulk them up as well, which would probably create a sufficient glow.

Thank you all again for your help.

 

[EZO]

Not sure what sort of budget you have for this idea but there are some ready made products on the market that are exactly what you are describing.

For example there is a place called (www)flamelesscandles.net that carries a whole range of products that might work for you like LED candles and tea lights, but like I said, some of these items could shoot your budget out of the water and obviously you don't need solar powered paper lanterns. I see they sell tea lights in bulk for a relatively modest price and I'm sure there are many competitors worth checking out. The Amazon links below may be more what you are looking for though.

This, may be a more affordable solution. (Floralytes)

Or this.

 

[MissPaqman]

Thank you, those are great ideas! Unfortunately, you're right- our budget is very tight. I have everything planned for under 6K, so we won't go into marriage in debt.

 

[Kandela]

Misspaq;

I'm with a few of these other people,I don't think you'll find a suitable solution from building at home.. The batteries posted by froggy are the cheapest I've ever seen, but still there's just not really enough to work with at the "home" level to make it cost efficient.. Depending on how big the wedding is (6K doesnt sound huge) I would just go with some of the other people's suggestions... Of course there is something pleasingly simple about buying a ton of batteries from froggy's reference, putting 2 in series for each light (60cents) and throwing a superbright bulk led across them (10-90cents), and wrapping it in electrical tape and calling it done. Thats like a thirty second per lantern job!

Honestly I really, really, REALLY think your best bet is going to end up being in 2 options. Either purchase the glow sticks like deadrx suggested... I've seen them everywhere, for ATLEAST 2 for a dollar.. You should be able to get them even cheaper online, and also specify colors, and I think you could light up twenty tables or lanterns with a dim "mood lighting" for around 20 bucks... Plus the extra's would be a hit with the kids. The other option I think you could go with is also what dealrx suggested, a 1$ flashlight... 99cent stores in my area have some surprising bright LED flashlights and book lights... purchase a variety before buying the final one in bulk.., to find the best one in your area... (they seem to vary greatly) You should also be able to light twenty tables or lanterns for around 20$ with this route (minus the initial "selecting" costs, 5-10$ or so..)...

You could turn it into a fun cheap idea, the 99cent stores in my area also have a decent shake-light that you shake to generate light, once the internal battery dies... You could buy 20 of these, and tear them apart to fit into some cheap cute containers, or colored glass candle jars or whatever... They would be candle like-bright, and last for awhile, but they arn't the best, I really don't know how long they last atfirst before you have to shake it.. own 2, but have never noted how long it took, usually I just started shaking it every now and then since I bought it and it works fine and bright, rarely have to actually shake it for light, just to "keep it charged"... anyways; After the wedding it would make cool thoughtful gifts, little jars that you shake to get some light for abit! Great wedding favors, i would keep one of my coffee table, instant light whenever you want!

If you can get ahold of the typical, name brand keychain lights, on sale, sometimes you can find them for around 1$.. these things are crazy bright, and would make great lantern lights or glass jar "candle" lights.. plus people could take the keychain lights at the end! Maybe get a label maker and make fancy labels for each actual keychain light?? You could also do this with some 99cent store lights..

All in all, as long as you're resorting to battery powered lights, I would definitely forget about making something cheap yourself on a budget, unless you can spend atleast 3$ on each light, otherwise I would go the 99cent per light option (batteries included), or glowsticks (even cheaper, lasts 4+ hours)

If you could ditch the battery route, and use the wall outlet for the lanterns or table lights, you have ALOT more options... It would probably still be in the 20$ range because you'd need a specific driver or converter depending on the led's you choose, but you could get alot, ALOT more light and options.. In my eyes the power source is the worst part of it... you're trying to go cheap, and batteries arn't cheap. Even at 30cents a piece, which is crazy cheap, who knows how long that will last, and you're already at 60cents per light (2 batts) compared to 1$ for some factory made lights, with batteries included for hours of light... that'll beat the price point of a home model ANY DAY...

 

[EZO]

There's a web site called "Big Wedding Tiny Budget" that touts "Fabulous Cheap Weddings, Tips Tricks and Techniques for Your Dream Wedding" and has a whole page about "Cheap Paper Lanterns, Lovely Illumination" which offers advice about exactly your idea!

This is one of the places they recommend for cheap paper lanterns and they have some for as little as 90 cents each. A place well known to folks here at CPF is DealExtreme (DX) and they sell a bulk pack of 50 white key chain lights for just over 22 dollars (45 cents each) with free shipping that are much brighter than the ones you first mentioned (22,000 mcd - a measure of "brightness" called millicandeldas). Just go to DX and do a search for SKU 3261 and you'll find 'em. I've purchased these before and they're great; they make great little gifts. It probably wouldn't be too hard to get these to work well inside a lantern (a little sandpaper on the LED lens would diffuse the light).

So if you can make this idea work for less than $1.50 per lantern it may just be your ticket.

Of course, you're planning to invite us all to your wedding, right?

 

[scott011422]

While not exactly what your doing, this may give you some ideas. This is what I made for my wedding. I just bought some 1400mcd 5mm blue leds from ebay and some CR123s from batterystation. I soldered 3 leds to each battery and stuck them into the stem slot for the flower holders. Cutting a little slot into the side long enough to stick some ribbon in, I had the ribbon seperate a spring from the battery. So all the setup people had to do was to pull out the ribbon to activate the leds. In this configuration the leds ran at full brightness for at least 2 to 3 days with another week at diminishing brightnesses. I also filled the glass with water untill it just touched the led, this help to more evenly scatter the light, and with the water to the center of the led, hide the led bright spot, so no glare.

 

[HarryN]

My daughter got married last year and Scott is right - that last minute setup / turning on all of the lights is something to consider.

I suspect that if you buy some of the Cree 5mm leds, you would find them reasonably bright with a small battery, but I am not sure if you can run them long enough that way without a resistor in the circuit.

I tend to know the Lumileds LEDs better, so I will comment on approach using those, but Cree also makes nice LEDs, so either brand can easily work.

If you look at their Rebel line of LEDs, they can handle quite a power range. You can get them for around $ 3-4 / each, and for about $ 1 - 2 / each, get them mounted on a star board. At the low power levels you are going to be running at, that is sufficient heat spreading.

Either using a CR123 primary cell, or a 3 v coin cell, hook them up to the star board. If you can add a 5-10 ohm resistor in -line, they will run for many hours., esp. on the CR123s.

These emitters (and the similar Cree products) emit over quite a large angle, are quite efficient, and you can get them in many colors, in fact, the Rebel is available in something like 11 versions of white alone.

At the low power levels you will be running at, they will all tend to run a bit "warmer colored" than the indicated CCT, but most people want that at weddings anyway.

Cost wise, the battery holder, CR123, resistor, Rebel, and star board will be in the $ 10- 12 / light for parts.

While I like LEDs, you might be able to hit a lower price point by purchasing some Energizer Li AAs and a flashlight bulb that runs on 1.5 volts. I doubt that you will want more than 50 - 100 lumens / light anyway.