Off the shelf retail store screw-in LED and CFL bulb comparisons

[ReikoX]

Mr. Sparkle,

I keep hearing you all talk about plexiglass, but its not necessary. That is the beauty of heat sinks. This will also work with screw in LED, the aluminum base is the heatsink in this case.

Start with a sheet of aluminum then cut holes big enough for the light.

Then attach this to the heatsink using thermal paste to get an airtight seal. Put a fan at one end and leave the other end open.

Now you have an LED cool tube with no plexiglass!

 

[Mr. Sparkle]

Mr. Sparkle,

I keep hearing you all talk about plexiglass, but its not necessary. That is the beauty of heat sinks. This will also work with screw in LED, the aluminum base is the heatsink in this case.

HPF and myself were referring to back to when either of us were using CFL's, for me that was over 8+ years ago, and before that i was using T8 floro tubes, it was either that P-ll's or small 150w and under hps and MH bulbs, leds weren't really an option unless you spent alot and built some big array with the cree xlamps that were just starting to come out at the time, like in 2008 cree had a lab setting of highest achieved lumen/w at around 160 or so if i recall, we surpass that now easily with off the shelf components.

Your method works, i'm not arguing that it was just in reference to a different time.

Also for the screw in LEDs if you made a plate that had holes a little larger than the diameter of the bulb, or have them sealed off but an opening on one end, and had a fan with your filter behind that plate it would act as a partial cool tube by sucking air through those gaps or end gap and would cool the bulbs or heatsinks without having to run two fans, it how i had a couple setups in the past laid out, or designed the boxes to have easy free airflow where hot air when say a fan failed could still exited out of the top of the box, if i was building or running a cabinet with some height to spare, i would do the whole bigger hole air gap around the bulb design then you could easily swap out bulbs when needed or desired.

 

[HuffnPufferfish]

no i used led on glass, to get rid of the heat radiating off the chips, it worked but it worked "too good"

now i just build a frame around them like its a regular led panel and get the hot air sucked out

right below the chips i still get 90+f temps, a heatsink doesnt fix that, and i was looking in getting the lights closer for efficiency

 

[HuffnPufferfish]

Or use T5/T8 replacement LED tubes and keep the diffuser on.

insane high startup costs, ranging from 40-70 and 5 for a regular tube

 

[ReikoX]

Your method works, i'm not arguing that it was just in reference to a different time.

Also for the screw in LEDs if you made a plate that had holes a little larger than the diameter of the bulb, or have them sealed off but an opening on one end, and had a fan with your filter behind that plate it would act as a partial cool tube by sucking air through those gaps or end gap and would cool the bulbs or heatsinks without having to run two fans, it how i had a couple setups in the past laid out, or designed the boxes to have easy free airflow where hot air when say a fan failed could still exited out of the top of the box, if i was building or running a cabinet with some height to spare, i would do the whole bigger hole air gap around the bulb design then you could easily swap out bulbs when needed or desired.

That's basically what I did with my filing cabinet. The fan in the center pushes through carbon and there is a vent at the back. Those are off-the-shelf LED for recessed lighting. About 21 watts on the package.

 

[n_d_ledz]

insane high startup costs, ranging from 40-70 and 5 for a regular tube

Not so true these days. Greenlight depot has 18w 4' bypass bulbs for 6 bucks. I dont know for flower, but Id love tubes for veg..

 

[HiKing808]

Reiko, how are you attaching the bulb socket? can you just fasten the bulb socket to the top of the pc case? or do you need something between for safety issues?

 

[frica]

insane high startup costs, ranging from 40-70 and 5 for a regular tube

Where I check, the replacement tubes are around 1 euro/watt for 150 lm/w tubes. (Philips Master)

Still more expensive than T5/8 fluorescent, but here electricity savings will quickly earn the money back.

 

[ReikoX]

Reiko, how are you attaching the bulb socket? can you just fasten the bulb socket to the top of the pc case? or do you need something between for safety issues?

These ones were for recessed lighting and had no sockets (convinient). They are held in place with silicone and pop rivets. You don't want them hooked up to the case as it would heat it up, you need an air gap.

 

[BruceBanner]

https://www.icmag.com/ic/showthread.php?p=7895884#post7895884

 

[frica]

hehe, im still here guys and still working away

I had a nitrogen deficiency most of the way through flower

With the overkill wattage (52w/sq ft)

I was thinking about your post again.

Light stress causes leaves to also go yellow like a nitrogen deficiency.
Did the leaves fall of, or could you pluck them easily? (if not, then it's likely light stress)

Light stress can easily mimick nutrient/ph issues.

Cheers on your future grows.

 

[mushulatubbee]

New leds/ first try

New leds/ first try

Oh really thanks!

 

[ratsidecar]

I was thinking about your post again.

Light stress causes leaves to also go yellow like a nitrogen deficiency.
Did the leaves fall of, or could you pluck them easily? (if not, then it's likely light stress)

Light stress can easily mimick nutrient/ph issues.

Cheers on your future grows.

They would pretty much fall off if you looked at them once they had turned fully yellow.

One thing I noticed with the bulbs packed so close together is that the philips 13.5w are showing small cracks around the white outer case, think its from the heat off them as the 8.5w ones are fine. Although canopy temps are still a non issue holding between 22C and 25C. Only time I have burnt a bud is when it was actually touching the face of the LED.

 

[mjconfid]

They would pretty much fall off if you looked at them once they had turned fully yellow.

One thing I noticed with the bulbs packed so close together is that the philips 13.5w are showing small cracks around the white outer case, think its from the heat off them as the 8.5w ones are fine. Although canopy temps are still a non issue holding between 22C and 25C. Only time I have burnt a bud is when it was actually touching the face of the LED.

My philips 13.5w did the same thing, and they aren't as tightly packed - the way those cracks look it's almost like case is made of some sort of ceramic?

BTW, not sure why 52w per sq foot is being described as overkill - back when I first looked into these bulbs, I did a comparison on a lumen basis using a cob calculator that I downloaded from rollitup.

Using cobs with the same color temp and CRI in the calculator I came the conclusion that 50w of screw in bulbs was a good amount to shoot for and was no way excessive.

If I recall correctly, 50w of those screw-in bulbs per sq foot comes out to around 900-1000 ppfd and that's an often recommended amount of led light to use.

 

[frica]

My philips 13.5w did the same thing, and they aren't as tightly packed - the way those cracks look it's almost like case is made of some sort of ceramic?

BTW, not sure why 52w per sq foot is being described as overkill - back when I first looked into these bulbs, I did a comparison on a lumen basis using a cob calculator that I downloaded from rollitup.

Using cobs with the same color temp and CRI in the calculator I came the conclusion that 50w of screw in bulbs was a good amount to shoot for and was no way excessive.

If I recall correctly, 50w of those screw-in bulbs per sq foot comes out to around 900-1000 ppfd and that's an often recommended amount of led light to use.

I think the calculator assumes a 1ft distance and assumes a 10% loss before reaching the canopy.

Ratside has the bulbs much closer to the plants than the average COB panel.

 

[mushulatubbee]

Come on wheres the know it alls?

 

[HuffnPufferfish]

Not so true these days. Greenlight depot has 18w 4' bypass bulbs for 6 bucks. I dont know for flower, but Id love tubes for veg..

i see they got 2ft's for 12$ thats pretty good, no clue on the spectrum but thats cheap enough, but im not gonna trow out my new tubes yet

 

[HuffnPufferfish]

typical 8 - 10w led puts out around 12.8 uMol/s

 

[frica]

typical 8 - 10w led puts out around 12.8 uMol/s

With the bulb removed it should be at least 10% higher since their listed light output should be with the cover on.

Typical optical efficiency for a secondary optical elements is 85%-90% (diffusers/lenses/etc.)

 

[brown_thumb]

QUESTION: If the increase in output below the bulbs is only ten percent then might it be better just to leave them on to increase diffusion and sideward dispersion?