Differences between Thermal tape

[Partisan]

Today I did a test run with a small led-strip that I adjusted to an aluminium strip with some tape that I got online for little money.

It's this tape: https://www.aliexpress.com/item/4000145 ... b201603_53



In the description it is said that the Thermal conductivity: 1.5W / m-K.
Now I know that those Chinese traders do not always take the truth very seriously.

There is also tape of 3M, type 8805.
I had read that this is actually the best tape that one could use.

https://www.3m.com/3M/en_US/company-us/ ... 801&rt=rud



In their description 3M says that the Thermal conductivity of this tape: 0.60 W / m-K.


It is my understanding the higher the W, the better the heat transfer is. Hope I am right there...

The 3M tape ($60-$80) is about 10 - 15 times as expensive as the Chinese tape ($4 - $ 7).

But what tape do the experienced members here think is better?

Are the Chinese not telling the truth? Is the Thermal Conductivity in reality not that heigh?

Or are they telling the truth and are we paying to much for the 3M Tape?

Who can shine some light on this?
Perhaps I am totaaly misunderstanding the numbers or even looking at the wrong numbers.

[Labgrown]

This "may" be enlightening. I won't comment on his experimental design... but hey its data.

[Partisan]

This "may" be enlightening. I won't comment on his experimental design... but hey its data.

I saw that already

But he didn't compare tapes, sadly enough

[TEKNIK]

So long as the Chinese tape sticks then it seems ok, don't stress about the exact performance. One way to check how well it is working is to measure the temprature at the board and at the base of the heatsink after everything has warmed up for a few hours.
Usually if the heatsink is getting hot it means the tape is working.
Key thing with strips is you don't want to be driving them really hard to begin with and the heatsink is there to help.
Using COBs is another thing. I would not use tape with a COB and only high quality thermal paste

[Partisan]

I glued the sensor of a thermocouple thermometer on top of the aluminium strip.
In the middle of the strip, right above the led-strip.
After 40 minutes the temperature of the strip was about 105 Fahrenheit / 40 Celsius and it stayed that way.

The room temperature was around 50 Fahrenheit / 10 Celsius.

Before I turned the led-light on, the temperature of the aluminium strip was about 52-54 F / 11-12 C.

I also glued the sensor at a different spot: the end of the aluminium-strip. That strip was perhaps 3 or 4 inch longer (at each side) then the led-strip.
So I glued the sensor at the end, and then the temperature was 90 F / 32 C after 40 minutes.


In the future I will glue the sensor on top of the led-strip, and see what the temperature will be.

[Welight]

If you need an analogy, consider this. The base structure of DS Thermal tape is fundamentally fibreglass, as such it is not dramatically different from the structure of PCB dielectrics used as insulators between copper and base on PCB. Given that it means to some extent what you have are two insulators blocking thermal paths to the heatsink. This does not mean it is not a good solution in terms of convenience and assembly or even performance, however it is not the absolute best performing solution, thermal pastes are certainly better, but are messy
cheers

[Partisan]

The led was from the brand TCI.
It is 24 Watt or 23 Watt (not sure)
TCI doesn't make them anymore, but here is a link of a fixture that used them:
https://products.light4u.io/wp-content/ ... CATION.pdf

[Partisan]

I did another test today.

This time I took just the led-strip (so no aluminium strip or heatsink)
It is plastic and bends a bit.
Room temperature was about the same 52 Fahrenheit / 11 Celsius.
Glued the sensor of the thermometer straight on top of the led-strip for this test.

Turned on the light and started measuring.
Fist thing I noticed was that the temperature was rising faster.
(I think because there was no cold aluminium to be heated up first)
After 5 minutes the temperature was already 106 Fahrenheit / 40.5 Celsius
After 30 minutes it was 112 Fahrenheit / 44.5 Celsius
Stopped testing at 40 minutes. The temperature stayed about the same. Sometimes a bit lower.

One thought I had was that maybe the temperature did not get higher, because of the cold room the test was done in.
So, perhaps some cold air above the sensor that cooled the sensor off.
That's why I took a piece of foam rubber.
Glued the sensor on top of the led strip, and with some tape I attached the foam rubber on top of the sensor.
Turned on the light again.
It all warmed up slightly slower, but after 25 minutes the temperature was about the same (110 Fahrenheit / 43 Celsius) as after 25 minutes with the test without a foam rubber piece.

Another thing I noticed that if I walked past the led strip and moved some air (just by walking by) you saw immediately the temperature go down. No big changes, but 0.2 degree or 0.4 degree. So I guess that even a tiny fan like the one's used in a car on 12 V or a computer fan, will bring the temperature down a few degrees easily.
Did not test it, but just a guess (and of course reading it on this and other forums)