LEDgardener

Hello everyone!
I decided to build the Bridgelux Gen. 2 BXEB-L1120Z 4′ LED Strip Build – 4’x4 but I am based in Europe and ordering the heat sinks from USA really raises my costs.
Can I replace the heat sinks with 25x25x2 mm U aluminium profile? Or will it get to hot?
The build asks for 12 four foot strips, is it possible to add 4 more strips and use the above mentioned aluminum profiles as heat sinks?

Thank you in advance

cabbage_head wrote: ↑

Tue Nov 26, 2019 9:53 am

Hello everyone!
I decided to build the Bridgelux Gen. 2 BXEB-L1120Z 4′ LED Strip Build – 4’x4 but I am based in Europe and ordering the heat sinks from USA really raises my costs.
Can I replace the heat sinks with 25x25x2 mm U aluminium profile? Or will it get to hot?
The build asks for 12 four foot strips, is it possible to add 4 more strips and use the above mentioned aluminum profiles as heat sinks?

Thank you in advance

Hey!

I can't really say with bridgelux as i dont have experience with those, but i use C-aluminum profiles for samsung f-series strips, single rows, at 700ma each, they run at 45c at the diode itself with no fans blowing on them.

I had to do the same as you, as im based in EU also, and heatsinks over here is a pain to get a hold of.

So i guess it would work, but wait for someone with experience with them to confirm for your build

At 1A per strip you are fine with that kind of aluminum.
Above 1.5A the aluminium gets too hot to touch after holding it for a few seconds. the highest reading on the diodes I could get was 77 C.

This is on 30*20*2mm U channel aluminium, and using the threaded rod method by @Nuggie 6mm rod thickness, 8mm drill size for holes (need leeway cause I'm a bad driller)

I use 2ft strips but they have the same stats. Just the voltage is doubled on 4ft (I guess cause they are made of 2x 2ft strips)


actually here are my notes testing at 1.8A:

"Front of strip temp readings: 55 (low) 62 (avg) 75 (high)
Aluminium gets uncomfortably hot after 5-6 seconds
Really hot but not able to get any readings above 76C"

0.9A:
"Front temps: 29 (low) 32 (avg) 41 (high)
I don't even feel heat
less heat more light"

I used 0.9A without heatsinks. Doesn't get too hot. If you put a fan on the strips that's a lot cheaper than aluminium. Not sure if this harms the strips lifespan.

Here is bare strip (no heatsink) test data https://www.rollitup.org/t/bridgelux-eb ... ls.957453/ At 0.7A they are totally completely fine without heatsink. If you use the same driver, but get 17 strips instead of 12, that gets them to 0.7A and you can build your light with no or minimal heatsink. 5 strips are cheaper than 48ft of aluminium. 16 strips would be fine too.

I could go 18 strips as it is cheaper and I assume that it will be more efficient this way. I will have to read the forums to find a good way of building the fixture.

Thank you guys for the great help.

gen 2 Bridgelux's can be ran bare at nominal voltage. Don't fret about heat sinking them, just buy a few extra strips, run them softer and call it a day. If you really want you could make a frame out of aluminum angle, and use angle or u bar to heat sink.

Sorry for the newbie question, by using u bar you thermal tape down the strip on the flat surface?

Pipsight86 wrote: ↑

Fri Jun 19, 2020 2:47 am

Sorry for the newbie question, by using u bar you thermal tape down the strip on the flat surface?

LED-newb here, do cooling elsewhere though. Most people use thermal tape but at least 3 additional screws per strip seem to help against tape coming loose. I just used more screws and thermal paste which was cheaper for me, but also takes more time to drill, apply paste and screw strips down. I like my electronics cool as can be though

cabbage_head wrote: ↑

Tue Nov 26, 2019 3:27 pm

I could go 18 strips as it is cheaper and I assume that it will be more efficient this way. I will have to read the forums to find a good way of building the fixture.

Thank you guys for the great help.

I got 20 strips, minimum offer (Gen 3), and made a fixture out of L-profiles only. That worked well, I got 2 x 3mm profiles for support and screwed down 20 x 1,5mm profiles onto those. It's on the cheap side, rigid and I would not want it to be heavier using more material.

sprout wrote: ↑

Fri Jun 19, 2020 3:32 pm

cabbage_head wrote: ↑

Tue Nov 26, 2019 3:27 pm

I could go 18 strips as it is cheaper and I assume that it will be more efficient this way. I will have to read the forums to find a good way of building the fixture.

Thank you guys for the great help.

I got 20 strips, minimum offer (Gen 3), and made a fixture out of L-profiles only. That worked well, I got 2 x 3mm profiles for support and screwed down 20 x 1,5mm profiles onto those. It's on the cheap side, rigid and I would not want it to be heavier using more material.

what driver did u use and pics