Anyone got some practical experience of these?

Is it sensible to stick them directly to the underside of (for example)
wall cupboards or is it better to stick them to some aluminium profile &
attach that to the cupboard?
This is DIY so I don't have to worry about the customer moaning that
it's not pretty.

From what I've seen, the aluminium strip cost more per metre than you
would pay for 5 metres of the 5050 LED Strip lights.


--
Sam

On Tuesday, March 11, 2014 10:01:47 PM UTC, Sam Plusnet wrote:
Anyone got some practical experience of these?



Is it sensible to stick them directly to the underside of (for example)

wall cupboards or is it better to stick them to some aluminium profile &

attach that to the cupboard?

This is DIY so I don't have to worry about the customer moaning that

it's not pretty.



From what I've seen, the aluminium strip cost more per metre than you

would pay for 5 metres of the 5050 LED Strip lights.

There are LED strips and there are LED strips. You need to consider the power dissipation of the ones you choose. Some do need heatsinking.

wrote in message
...

On Tuesday, March 11, 2014 10:01:47 PM UTC, Sam Plusnet wrote:
Anyone got some practical experience of these?



Is it sensible to stick them directly to the underside of (for example)

wall cupboards or is it better to stick them to some aluminium profile &

attach that to the cupboard?

This is DIY so I don't have to worry about the customer moaning that

it's not pretty.



From what I've seen, the aluminium strip cost more per metre than you

would pay for 5 metres of the 5050 LED Strip lights.

There are LED strips and there are LED strips. You need to consider the
power dissipation of the ones you choose. Some do need heatsinking.

I bought a 5 metre roll to make a coolant proof light for use inside a
machine tool. This involved sticking three rows of them to a core of 6 mm
polycarbonate rod arranged at 120 degree intervals, and then sliding the
assembly into a polycarbonate tube with end seals. When I first did it I
tried the lights before making the final seals, and over a period of maybe
30 mins they warmed sufficiently for the glue to soften and stick to the
tube, resulting in me not being able to slide the assembly out again I
pulled them out brutally which tore the strips, and with a new roll started
again in the light of experience. The light was entirely successful, and let
me stress they didn't get hot, just warm enough for the glue to migrate. The
result was greatly improved lighting inside a totally enclosed CNC lathe
where the environment is rather aggressive with high pressure coolant and
swarf flying about.

Andrew

I got some on Ebay from a Chinese supplier - 5 metres long with a kind of clear protective covering over the entire length to make them weatherproof.

I've got them stuck directly to the undersides of my kitchen cupboards and down near the plinths of my kitchen units. They work very well and don't give off any heat that I can detect. No need to attach them to anything to dissipate heat in my experience

On Tue, 11 Mar 2014 22:01:47 +0000, Sam Plusnet wrote:

Anyone got some practical experience of these?

The strip didn't stick very well to clean copper.
I stuck a couple of metres of LED strip to a copper heatsink:
http://i39.tinypic.com/9gbo90.jpg

After 20 minutes they got rather too hot, so I put a fan out the back,
and that works fine.
If you don't have the strip close together like mine, they should not get
hot.

In article ,
MattyF writes:
On Tue, 11 Mar 2014 22:01:47 +0000, Sam Plusnet wrote:

Anyone got some practical experience of these?

The strip didn't stick very well to clean copper.
I stuck a couple of metres of LED strip to a copper heatsink:
http://i39.tinypic.com/9gbo90.jpg

After 20 minutes they got rather too hot, so I put a fan out the back,
and that works fine.
If you don't have the strip close together like mine, they should not get
hot.

It's about the heat dissipation capabilities of the enclosure.
When I'm building an LED light which might have heat issues,
I usually experiment first using some power resistors fixed
where the LEDs will be, and measure their surface temperature
increase over the room temperature, to work out the thermal
resistance of the enclosure, and hence what max LED power I
can put in there for some max ambient temperature.

Forced air cooling makes an enormous difference, but also
stops the unit being maintenance free as it will require
periodic cleaning.

Another thing you can do is reduce the LED power input as
the unit reaches the max safe operating temperature. There
are some LED PSUs which have that capability, and/or a
variable fan output, which are used in some high power LED
lights.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Thu, 13 Mar 2014 12:37:02 +0000, Andrew Gabriel wrote:

It's about the heat dissipation capabilities of the enclosure.
When I'm building an LED light which might have heat issues, I usually
experiment first using some power resistors fixed where the LEDs will
be, and measure their surface temperature increase over the room
temperature, to work out the thermal resistance of the enclosure, and
hence what max LED power I can put in there for some max ambient
temperature.

Forced air cooling makes an enormous difference, but also stops the unit
being maintenance free as it will require periodic cleaning.

In my case the ambient temperature underneath the LED lights was rather
high. This is what is a couple of feet under the LEDs:
http://i48.tinypic.com/287jawz.jpg

I had to get cold air from elsewhere to blow on the LEDs.

In article , says...

On Thu, 13 Mar 2014 12:37:02 +0000, Andrew Gabriel wrote:

It's about the heat dissipation capabilities of the enclosure.
When I'm building an LED light which might have heat issues, I usually
experiment first using some power resistors fixed where the LEDs will
be, and measure their surface temperature increase over the room
temperature, to work out the thermal resistance of the enclosure, and
hence what max LED power I can put in there for some max ambient
temperature.

Forced air cooling makes an enormous difference, but also stops the unit
being maintenance free as it will require periodic cleaning.

In my case the ambient temperature underneath the LED lights was rather
high. This is what is a couple of feet under the LEDs:
http://i48.tinypic.com/287jawz.jpg

I had to get cold air from elsewhere to blow on the LEDs.

Hmm.

I was intending to buy a 5 metre reel of 5050 LEDs & use in one or two
awkward corners at home, but one place I had in mind was directly above
the cooker hob in the caravan (wife is always complaining about the poor
light there).

I can easily attach them to the underside of a wall cupboard above the
hob and 12v is not a problem, but I was concerned about the sum total of
heat from the cooker + the LEDs themselves.
However yours[1] is a lot bigger than mine.


[1] Heatsource.

--
Sam