Vintage flashlight LED project for lighting baked goods display

[Culpritcoffee]

Hey there. I've just joined the forum looking for some information on LEDs in regards to a project I'm about to take on.
I've just opened a coffee shop in Vancouver BC and have a display case full of baked goods that I'd like to light with a wavelength spectrum that makes them look their delicious best.
A friend who is embarking on a lighting design career designed a very cool chandelier from vintage flashlights. It uses LEDs that were scavenged from Ikea lighting products that emit a very cold white light. I'd like to replace these with LEDs that produce a much warmer light that will compliment the browns and warm yellows of the baked goods.
The transformers in the current design are hidden in the cover plate on the ceiling and the low voltage leads from the transformers run down individual cables into each flashlight.

I'm looking for help with deciding which type of LED is best for this task, an idea of whats involved design-wise to install the new LEDs and a good source for the LEDs and any other components I might need.

I have an image but haven't been able to figure out how to attach it.

Thanks!

[purduephotog]

Hey there. I've just joined the forum looking for some information on LEDs in regards to a project I'm about to take on.
I've just opened a coffee shop in Vancouver BC and have a display case full of baked goods that I'd like to light with a wavelength spectrum that makes them look their delicious best.
A friend who is embarking on a lighting design career designed a very cool chandelier from vintage flashlights. It uses LEDs that were scavenged from Ikea lighting products that emit a very cold white light. I'd like to replace these with LEDs that produce a much warmer light that will compliment the browns and warm yellows of the baked goods.
The transformers in the current design are hidden in the cover plate on the ceiling and the low voltage leads from the transformers run down individual cables into each flashlight.

I'm looking for help with deciding which type of LED is best for this task, an idea of whats involved design-wise to install the new LEDs and a good source for the LEDs and any other components I might need.

I have an image but haven't been able to figure out how to attach it.

Thanks!

GE makes display case lighting. You can use them as a reference - GE VIO was their product line.

[Yoda4561]

I can't really help much with the design aspects, but I can at least assure you that there exists an LED that will work for your application. High CRI is not necessary to make something look good, but doesn't hurt when it's in the same color temperature region you want. Look for LED's with a color temp between 3000 and 4500k. I think 3000 would be better for baked goods unless you have lots of blue/purple colorful toppings/decorations in which case lean towards the 4000k region. Just to throw some names out, Cree has the XPG High CRI 3000k, MTG and MTG 2 leds, XM-L. There's also the Nichia 219, which is really gaining in popularity right now as it's the first led available that combines 4500k and High CRI.

[Culpritcoffee]

Thanks yoda and purduephotog.

I had a look at the xpg's and as an LED rookie I want to be sure I understand exactly what they are. So it looks like they are groups of individual LEDs soldered onto a board? There don't seem to be any specs on voltage,current, size of the board. They do come in a warm white of 2600K to 3700K which should be perfect for lighting our cookies and muffins.

Can anyone chime in with that info? How do I know what's required for power supply etc?

Thanks.

[Yoda4561]

The LED's are usually available bare (this is a clear dome mounted to a flat square just barely larger than the dome, that assembly is the LED), or pre-soldered onto a PCB to make them easier to use(usually silver colored, much larger than the led, and round or geometrically shaped with cutouts. 10-20mm diameter PCB's are common and most have large copper/gold colored soldering pads. Either way, you need to have some kind of heatsink to mount them to, usually with flashlights this is handled by the metal flashlight body itself, or an aluminum strip that the pcb's are mounted to, etc.

There are a variety of LED drivers available, some for a single LED, and others that need to drive multiple LED's off of one driver. That usually requires the LEDs be wired in series. For specifics you'll need to look at the datasheets for the drivers and LEDs to see how everything matches up, there's not much in the way of "plug and play" as 120v AC powered LEDs never caught on for various reasons. Check out Cutter electronics and LEDsupply to get a look at a variety of products.

[Culpritcoffee]

Thanks again yoda.

I'll check the spec sheets and I'm sure I'll be back with more questions.

Do you know if anyone on the forums might be able to help with choosing or building a driver?

Cheers.

[blasterman]

Why would you want to build a driver? They are cheap commercially......

I just went through a project like this at a restaurant, and after going through about half a dozen LED colors the one thing we found is that you really want to stay between 2700-3000k and no higher when lighting food. At low color temps LEDs have inherently their highest color rendition and do the best with food. 2700k LEDs are available from both Cree and Rebel, and while this is something easy to build I'm nut sure why you'd want to when SMD based strips are available that run on 12volts and can do the same job. Plus, having something slapped together over food might have potential ramifications with health code rules. More than likely they'll never notice, but this is just a product I'd rather do with high quality LED strips -vs- DIY.

[LEDninja]

Are the flashlight bodies metal? Needed to conduct away heat. LEDs do NOT like heat.
How big is the head of the flashlight?

You are in a commercial environment. What you build needs to meet code. More importantly YOU need to EXPLAIN to the electrical inspector HOW your project meets code.

If the flashlight head is more than 2 inches in diameter, you can have a certified electrician put in a 12V display case lighting system with MR16 fittings and using your flashlight bodies as 'lampshades'. Then go to Home Depot and pick up some PHILIPS 3W LED MR16 Soft White bulbs.
24V or less does not have to meet the electrical code, just the fire code. (For example all plastic parts have to be fire retardant.)
The 120V to 12V part have to be CSA approved and installed by a certified electrician. (If he signs off on it you don't need the electrical inspection.) The 12V part you can go to town on your own.

[blasterman]

Then go to Home Depot and pick up some PHILIPS 3W LED MR16 Soft White bulbs.

Bad idea, although the logic is good.

Nothing you're going to buy at a big box store in retrofit format is going to guarantee color temp with LED's. Even though that box may say 'warm-white' you may be getting 6000k LED's, or 3500k, or 4500k. If you buy a Cree made fixture from that store and it say's "2700k" I'll believe it. Anything else and you're throwing darts. Lighting food to make it look god is a very particular science, and it's very easy to defeat your purpose with artificial light sources unless you are specific about color temp and CRI.

MR-16 LED bulbs also tend to be very directional, which means they will either have to be elevated quite a ways over the product, or you'll have to use a lot of them. SMD strips will be easy to hide, safe, and at 2700-2900k using quality emitters the product will look very appetizing.Plus, they're easy to tweak by adding more or subtracting. The problem though is there's a lot of junk on the market and you want to stick to reputed sellers.

[Culpritcoffee]

Thanks to everyone for their input.

Blasterman...as a rookie I don't know what's available or what specs for a driver I would need. Also, I'm attempting to modify an existing project that is essentially a chandelier consisting of eight vintage flashlights hanging from a ceiling plate. Currently the ceiling plate conceals two ikea transformers that are powering the led's that are installed where the lenses once were. All I want to do is replace the existing cool light led's with warm white led's of a higher power. I wish I could attach a photo but that doesn't seem possible from an iPad. I definitely appreciate your advice re the spectrum that works best with food!

So presumably then I'll need:

LEDs
transformers
a board to mount each group of LEDs that can be trimmed to fit inside the flashlight lens
And...drivers too?

The flashlights range from 2.5" diameter lenses to 4". So you're saying there's a ready made LED bulb that should fit inside?

[blasterman]

Sorry dude, I read the part about you having a display case and assumed that took priority over the flashlight chandelier. I can see why LEDNinja headed down the MR-16 route. For the record I stopped by a Tim Horton's tonight and they were using a single SMD strip in each of their baked goods cases.

If you're friend modded the vintage flashlights with cold-white LEDs then use the same method and replace them with 2700-3000k LEDs. I'm assuming your friend is using a current resulted DC/DC driver in each flashlight. Otherwise, this sounds like a retrofit on a flashlight per flashlight basis.

[Culpritcoffee]

So the high output mr-16s put out 470 lm each. By my calculations that's about equivalent to a 35 W incandescent bulb? With 8 flashlights then that's about 278 W incandescent equivalent. I'm sure that's a lot more than what I have now and might just be enough to light the display case which is only about 48" x 32". It seems to have a fairly narrow beam though which isn't ideal. Maybe I can install a couple of them so that they're cocked inside the flashlight and cover a wider angle.

If I want to use the mr-16s how do I figure out what I need to power them?

[Culpritcoffee]

I went to an electrical supply shop today to check out the MR-16's. I don't think they'll work for my application just because they don't have the power I need and have a narrow field.

So I'll likely have to build a board for each of the flashlights, each of which contains at least a few LED's.

So any help you guys can provide would be HUGE! Where do I even start with sourcing the individual LED's? I mean, sure I can find websites that sell LED's, but:

Who has good deals?
What are the signs of a quality LED?
Aside from wavelength, brightness and voltage, what are the other key specs?
Aside from a heat sink and transformers, what other components are required for the design?

Thought I'd be posting photos too now that I'm working from my home computer but I see the forum only allows posting from image hosting websites so I guess it ain't gonna happen. The last thing I need is yet more accounts at yet more websites, especuially just to post a photo or two.

Thanks again.

[LEDninja]

Thought I'd be posting photos too now that I'm working from my home computer but I see the forum only allows posting from image hosting websites so I guess it ain't gonna happen. The last thing I need is yet more accounts at yet more websites, especuially just to post a photo or two.

There are 2 free websites that CPF members tend to use for photos. http://photobucket.com/ and http://imageshack.us/. Just use your CPF username and password. You may be already registered at a website that allows hosting pictures.

[purduephotog]

I went to an electrical supply shop today to check out the MR-16's. I don't think they'll work for my application just because they don't have the power I need and have a narrow field.

So I'll likely have to build a board for each of the flashlights, each of which contains at least a few LED's.

So any help you guys can provide would be HUGE! Where do I even start with sourcing the individual LED's? I mean, sure I can find websites that sell LED's, but:

Who has good deals?
What are the signs of a quality LED?
Aside from wavelength, brightness and voltage, what are the other key specs?
Aside from a heat sink and transformers, what other components are required for the design?

Thought I'd be posting photos too now that I'm working from my home computer but I see the forum only allows posting from image hosting websites so I guess it ain't gonna happen. The last thing I need is yet more accounts at yet more websites, especuially just to post a photo or two.

Thanks again.

Major manufacturers will provide all the data you need here. Dedicated fixtures and lighting suppliers have this as well.

I suggested GE. Goto Cree.com and check out their troffers. There is also several white papers on the cree site talking about lighting solutions for various areas and restaurants, many of which are going to have had the same concerns you did.

Anyways, you aren't looking at LEDs here- you are looking at lighting solutions, so many of the questions you have can be relevant but are answered elsewhere.