DIY light fixture's

[I'mIn]

I have an office light fixture that uses these tiny inefficient halogens that cost too much to buy and always burn out. So I plan on installing an led setup. It needs light entensive throw in specific locations, such as my desk. I have some laptop power supplies laying around and I plan on making the current regulators myself, so the big costs are the LED's and the light fixtures.
A cheap, but effective light fixture that has adjustable lighting directions is what I'm after. I would love to do a modification to the existing fixture, which has a flat brass bass with four holes where the halogens went. I'd like to use those holes and maybe run some flex wire conduit in each of them to direct the lights, and an outer sheathing to cover the fittings.
Any cheap DIY ideas for housing the led's, not to mention heatsinking, reflectors, bases, etc, please share with me and others your insights no matter how small.

 

[Fallingwater]

I don't mean to spoil your fun, but if you are able to remove the existing halogen fittings you'd probably get better results with a lot less money by using a tube fluorescent, or even a CCFL.

 

[I'mIn]

Your probably right, however my power bill needs some serious help! Also this is as much as a new hobby as anything else and I have most of which I need already. So I'm going to do it anyway. Thanks for your response.

 

[I'mIn]

Also I don't think there are cfl bulbs small enough to fit, the screw cap is about a 1/2 inch in diameter. Do they make CFL's that small these days?

 

[DM51]

Welcome to CPF, I'mIn.

I think this thread would fit better in Fixed Lighting, so I'll move it there.

 

[SafetyBob]

If your worried about your power bill, then don't use those horrible laptop power supplies, use the state of the art LED drivers by advance or I also like the Mircrodriver's too.

The B/S/T forum should also give you some good leads to optics.....spot optics work very well for my Cree LEDs.

Heatsink, think aluminum and use the Artic Aluminia Epoxy to glue the leds to the heatsink.

Bob E.

 

[Ken_McE]

I have an office light fixture that uses these tiny inefficient halogens that cost too much to buy and always burn out. So I plan on installing an led setup.

A man after my own heart.

It needs light entensive throw in specific locations, such as my desk. I have some laptop power supplies laying around and I plan on making the current regulators myself, so the big costs are the LED's and the light fixtures.

Are you thinking a store bought LED bulb, something like an MR-16 maybe, or are you planning to build your own?

A cheap, but effective light fixture that has adjustable lighting directions is what I'm after.

You could start with a track light like this one:

http://www.lowes.com/lowes/lkn?action=productDetail&productId=93188-17771-W466BN&lpage=none

Just change the power supply and pop in some LED bulbs. This would give you a finished appearance with little effort.

I would love to do a modification to the existing fixture, which has a flat brass bass with four holes where the halogens went.

Sounds almost like a ceiling fixture turned upsidedown.

I'd like to use those holes and maybe run some flex wire conduit in each of them to direct the lights,

Is this a sort of goose-neck material?

Any cheap DIY ideas for housing the led's, not to mention heatsinking, reflectors, bases, etc, please share with me and others your insights no matter how small.

A technique I favor is to stroll through a hardware store and look at what is already on the shelf, particularly in the plumbing and electrical aisles. There is always a good slection of cheap ready-made parts, althought not reflectors and lenses. If you live near a "Bed Bath & Beyond" store they have a lot of clear and translucent things to mount the emitter in.

The entire project sounds like fun and I hope you'll consider posting a few pictures.

 

[I'mIn]

SafetyBob with a name like that I'm glad I've got your help, thank you. I bought some Arctic Silver. Thanks for referring me to the B/S/T I never would have looked there because I don't know what B/S/T stands for, it has a lot of valuable information.

Ken McE: Yes, goosenecks was what I was talking about, however, everywhere seemed to pricy for me, so I went with some cheap conduit by the foot at HD. I'm planning on sawing off the anchoring system from the old bulb mounts, and epoxying the conduit into it so I won't need any expensive threaded goosenecks.That tracklight is sweet! I've been keeping my eyes peeled at the second hand store for something like that, I'm trying real hard to keep this project cheap enough to justify it, and yet still nice enough to justify it as well.

So now what types of leds and optics should I get? There's four places to install my cunduit plus an area in the middle I could mount an extra led directly to the fixture. So that's a total of 5 LED's if they all only contain one led. My ceilling is only 8 feet tall with about 8X9 foot walls. I really only need to throw light at my desk and 2 or 3 other places. So could I get by with a bare minimum of one High L/W ratio LED per light with the correct optics and high enough current provided? Let's say a warm light Cree XR-E upper bin(q5,R2,etc) powered at 750mA, with the GU10 LED Spotlight Housing here for 6 bucks: http://www.dealextreme.com/details.dx/sku.15085. Also would this kit be sufficient to handle 0.7Amps or would I need something more?

 

[SafetyBob]

Those spotlight housings look good for something to start with. After you put together some, put them up, then start thinking that there has to be something better....


Yes there is.....find an old CPU heatsink or perhaps some round aluminum solid stock....glue some led's of your choice to them, LEDIL optics (spot or flood) and you will be able to zero in that custom made like exactly where you want it......been there done that.

Ok, I can't leave with just the above. I recommend either 3000K or 4000K color temp LEDs. This may bring you away from Cree and towards Seoul. I know Mouser has the Seouls (P4's) in the main three color temps (3,000; 4,000; 6,500). They will work as well as the Cree's.

I was also very, very excited when I started reading about the Cree Q5's and such, but came down to reality when for the most part they were hard to find and kinda pricey, and....when I first made my first in-the-house light.....it was WAY to bluish tint for me (and even the wife made mention of it but she didn't know what to call it).

Seoul.....Mouser......P4......4000K.......get em.

Bob E.
Bob E.

 

[I'mIn]

Thanks for staying with me.
Yes, I have heard good things about Seoul's package and pricing and your advice is convincing, especially the part about the important color temps! I was thinking about those cpu heatsinks and may still go that route because I don't want to spend more than $5 for just one heatsink for one LED. The only beef I have with it is it's a little less cleaner looking than what I wanted.

The only single SSC LED reflector I found from LEDIL is the P7 boom reflector types and I don't know how a P4 would work in it. With the P4's lower profile would it have less spill than the p7 in the same reflector? Anyone with experience mixing the two?

 

[Paul Baldwin]

Hi
How about an equivalent to these? http://www.rapidonline.com/Electron...fin-heatsink-25-x-25-x-15mm/78531/kw/heatsink It seems i went totally over the top with the pc heatsinks i used in my led project!

Paul.

 

[I'mIn]

Thanks Paul, their heatsinks are much better priced than the digikey ones I had been spying on.
So because of searching fatigue I've decided on the following: conduit, 56-pin heatsink(listed above), seoul P4's(spectrum undecided), khatod's KCLP17CR 17mm reflector, and a sixer of cold IPA to keep things from running too hot.
In the not so immediate future I will post some pix of the project for ya'll.
peace

 

[FrontRanger]

...when I first made my first in-the-house light.....it was WAY to bluish tint for me (and even the wife made mention of it but she didn't know what to call it).

Ah yes, that. My wife has seen the tint of my high-flux-bin Cree flashlights, so when I told her I was going to make an LED-based light for our bedroom, she said, "Well, don't make it look like the inside of a prison."

Seoul.....Mouser......P4......4000K.......get em.

Thanks for the tip. I'm still looking for a nice neutral-white ~3W LED of moderate price to utilize around the house. I've watched a few "feeler" threads on CPFMP and they haven't panned out, so maybe I'll try these. Here are all of the 4000K, "3.8W", SSC power LEDs, and the only one on a star is this, so I'm guessing that's the one you're talking about. I looked at it on the online catalog here, and the ratings look funny: 3.2 V, 0.8 A, and only 60-70 lm? Normally the 60-70 lm range is when the LED is driven at the pseudo-standard 350 mA (to create nominally-1W power dissipation). Do you have these, and can shed some light on this (no pun intended)? Or perhaps you meant another part entirely? Thanks!

 

[2xTrinity]

Ah yes, that. My wife has seen the tint of my high-flux-bin Cree flashlights, so when I told her I was going to make an LED-based light for our bedroom, she said, "Well, don't make it look like the inside of a prison."



Thanks for the tip. I'm still looking for a nice neutral-white ~3W LED of moderate price to utilize around the house. I've watched a few "feeler" threads on CPFMP and they haven't panned out, so maybe I'll try these. Here are all of the 4000K, "3.8W", SSC power LEDs, and the only one on a star is this, so I'm guessing that's the one you're talking about. I looked at it on the online catalog here, and the ratings look funny: 3.2 V, 0.8 A, and only 60-70 lm? Normally the 60-70 lm range is when the LED is driven at the pseudo-standard 350 mA (to create nominally-1W power dissipation). Do you have these, and can shed some light on this (no pun intended)? Or perhaps you meant another part entirely? Thanks!

The specs are very confusingly written. The way I read it, 60-70 DOES in fact refer to lumens @ 350mA. Notice this number is the same for the ~1W LEDs, even though current there is listed as 400mA... I can guarantee those parts aren't double the efficiency of the higher power emitters (if they were, it would be downright idiotic to buy the higher power emitters).

Current refers to MAXIMUM current (makes sense as it's lower for neutral compared to cool, Neutral does usually have slightly lower max current spec).

 

[FrontRanger]

The specs are very confusingly written. The way I read it, 60-70 DOES in fact refer to lumens @ 350mA. Notice this number is the same for the ~1W LEDs, even though current there is listed as 400mA... I can guarantee those parts aren't double the efficiency of the higher power emitters (if they were, it would be downright idiotic to buy the higher power emitters).

Thanks. That was my suspicion exactly, namely that the specified voltage, current, and flux ratings were not all simultaneously applicable. Glad you get the same impression. Mainly I was curious if SafetyBob (or anyone else) had those, just to confirm.

Current refers to MAXIMUM current (makes sense as it's lower for neutral compared to cool, Neutral does usually have slightly lower max current spec).

Yeah. I'm planning on a 700 mA Xitanium, unless I come across something nicer, so that'll be fine.

 

[SafetyBob]

Yes, I did notice that too at the time and did all sorts of going back and forth to all the data sheets for all the listed LEDs towards the bottom of the page at Mouser.

That's why I went strictly with the 3.8 Watt types, as far as I could tell, they were the latest, greatest and seemed to output as much or more lumens as the lower wattage ones.

I have not done a side by side comparison with the same led temp from the 2.5 watt and 3.8 watt camp.....sounds like a challenge, however, I have not been disappointed with the 3.8 watt leds.

And I run some at 350mA and some are at 700mA and both setups have done exactly what I needed so I really am not interested about anything else.

I like simple and easy, and for me those 3.8 watt leds have made my projects simple and easy, the only thing I need to do is decide just how much light I really want.

Bob E.