Led Shop Light Retrofit

[Ulma Doctor]

I've been in the planning stages for too long on an idea for retrofitting my shop light.
Above my bench there is a 4' - 2 bulb, fluorescent T8 fixture, that i'm retrofitting with LED lighting.
I traded the LED's , drivers, and filters from a member- Matthemuppet , awhile ago and haven't put them to use until now....



I ordered some 1/8" x 2" x 36" 6061 aluminum flat to use as the mount and heatsink for the build.


using the 1watt LED as a template. i laid out the locations and marked out the hole positions for drilling/tapping 6-32 attachment screws and bored holes for pass thru of the wiring in the aluminum flat.
I used Heat Sink Compound on the LED/Aluminum flat interface for maximum heat transfer. The Flat is not only the support structure, but it's lot of area for heat dissipation!



I decided against using the machine screws because the heads were too large and presented a possible electrical malfunction or a short in the circuit that i want to avoid.
i chose instead , for socket head cap screws (allen head) due to their smaller head diameter.
the smaller head doesn't interfere with electrical conductivity of the LED.


here's a look at the LED driver, it's really quite simple.
to utilize the driver you'll apply 110v to the white legs on the right side of the picture.
the driver steps the voltage down to just over 13vdc.
The Red wire is +, the Other White is -.
Led's should not be hooked up in parallel, premature failure is likely.
This circuit is a series connection, there is 5- 1 watt led's in the circuit.
I soldered up the series connections directly on the led's and wire nutted the driver in for testing purposes.
here's the test photo,
these are the only lights on in the shop!

i ran the test for 15 minutes without smoke or flames, so something must have went right!!!

in the next episode, i'll be mounting the array into the shell of the old shop light and reassembling.
as always thanks for reading, comments/questions are always welcome!

 

[brino]

Hey Ulma Doctor

Would you mind giving a ball-park cost for this upgrade?

I can't wait to hear your thoughts on the final product with reflector and mounting.
I'm sure the colour will be better than fluorescent, will it have equivalent brightness?

I could see converting all my lighting over as the bulbs die, if the price is okay.....

Thanks!
-brino

 

[Ulma Doctor]

Hi Brino- thanks for reading,
if i were to give an estimate of materials cost, it would be around $20-30.
i'll be honest, i have only a couple ideas as of yet for mounting the diffusers- nothing set in stone.
the color is a bright white, i can't say for sure yet if the brightness is going to be equivalent.
but i will say that you can look at a fluorescent bulb , you can't look at an LED without squinting-
i don't know yet how that's going to translate into useable light.

i have purchased some other LED bulbs that screw into normal bulb holders, but haven't rec'd them yet.
it will be interesting to see a comparison, the set up i made is 5 watts- the bulbs i purchased are 9 watts
i'll put them toe to toe and see the difference

you are very welcome, anytime!
mike

 

[chips&more]

Very Nice Job! This is very arbitrary, but figure ~ 100 lumens/watt for a LED. So in your example ~500 lumens. The equivalent of just under a 40W incandescent light bulb. Or about the equivalent of one T8 fluorescent, again “about”…Good Luck, Dave.

 

[Ulma Doctor]

Thanks chips&more for the info!

 

[mattthemuppet2]

woohoo! Great to see you doing this, I guess my badgering must have worked For the next one try 4-40 cap head screws if you want, those are what I use.

I use non-acetic acid silicone sealant for the optics as they're easy to pull of if you want to change things around. Depending on what you want to use the light for, you can go bare (I'm not so keen because of the glare) for widest angle, optics without holders for some focus and some side spill or optics will holders for spot lighting, say if it was above a bench or a lathe. I'm going to take the optics out of the holders on the lights I have to get a little more side spill and a bit more even lighting, so they overlap a bit better. They're never going to be super bright lights, but they are very very efficient.

chips - I'd have to look up the datasheets, but these Nichia 119 LEDs are reasonably efficient. Something like 70lm each at that drive current (250-300mA), but the biggest draw is 90+CRI and neutral white (~4500K), so things actually look the colour that they are

brino - driver was $2-3, LEDs (bare) are 60c-$1 but you have to reflow solder them onto alu stars ($2 for 10) - if you want to skip this you can get presoldered LEDs on stars (Nichia 219A or B are awesome) for $3-4ea, optics are from memory 40c ea from LED DNA. If you want links to all of that you'll have to give me a moment as I have a meeting in 15min and need to buy some cookies. The lights are relatively low powered so any chunk of alu scrap that has a reasonable surface area will do. I've used everything from 1in.sq alu tubing to 80-20 lengths.

Mike - btw, I'm finally getting round to using that 3/4-16 tap you traded me to make a chuck backplate. I've used a bunch of the others though, sadly I even broke the tips on a couple of 4-40 taps, but the rest are going fine

 

[RJSakowski]

Very Nice Job! This is very arbitrary, but figure ~ 100 lumens/watt for a LED. So in your example ~500 lumens. The equivalent of just under a 40W incandescent light bulb. Or about the equivalent of one T8 fluorescent, again “about”…Good Luck, Dave.

A 40 watt T8 fluorescent actually has around a 3,000 Lm output.

One term used to describe output efficiency is efficacy which is related to useful light output. Most light sources emit light in a 360 degree pattern. Some of the light can be reflected but a good portion is absorbed. LED's typically emit light in one direction with a 120 degree cone angle.

I have made extensive use of LED lighting over the past nine years. Our kitchen is lit exclusively with LED's and I have a 5m strip for illuminating a porch. I also use them for work lighting on my Tormach, and lathes. The Tormach lighting outputs 900 Lm. and the lathe lighting outputs 800 Lm. each.

LED lighting is getting more practical all the time. However, it is still comparatively expensive. When shopping, I look at the lumen output. I will not buy an LED unless it is specified. High bright or super bright don't cut it. I also look at $/Lm.

Recently, a local DIY store had 60w incandescent bulb replacements for less than $5 each; 800 lm output. This is a rather easy way to upgrade. My basement shop still has ten 40w fluorescent lamps, somewhere around 30,000 Lm total. Were I to replace them with an equivalent light output, I would be looking at several hundred dollars at best. It may be a while before I get to replace those.

 

[RJSakowski]

For those anxious to get on with it, LED Supply sells a Cree CXA-1310 6mm array, 1300 Lm. output for less than $9.00. A pair will provide more useful light than a 40w fluorescent tube. You would definitely want a diffuser with those puppies though!

 

[Ulma Doctor]

Matt & RJ,
thanks guys for reading!!!!

Matt you were instrumental to my getting off my often lazy backside!!!
Thanks for the nudge!!!!
I'm glad to hear you're making use of the taps.
I'm a little too heavy handed to use a tap smaller than 6-32.
I have broken way too many small taps in both metric as well as imperial,
so i try to avoid the aggravation by using the next size up whenever possible.

RJ,
thanks for the information as well as the source for the 1300Lm gear- i'll be seriously looking into them!

 

[GarageGuy]

I'm working on a similar lighting project for my lathe. I found 10 watt white LEDs for $3 each, and will mount them to a piece of aluminum angle for a heat sink. The aluminum angle will mount to the bottom of a shelf over my lathe. The leg on the angle will shield my eyes from seeing the LEDs directly. I have 2 of the LEDs to experiment with. They are very bright, and only draw 4 watts of 115v each. The final layout will use about 10 of them. When the project is out of the design/experiment stage and in the build stage, I'll get some photos.

GG