can the leds be mounted into spray foam insulation

[Crafts4Me]

hi
these are the 12v leds - 12v 5w

https://www.aliexpress.com/item/1005007003088426.html?spm=a2g0o.order_list.order_list_main.82.5aa71802avX94p

my application is on spray foam insulation polyurethane foam (SPF), with a bulb cover
is that safe or the foam will melt?
please advise
thanks

 

[Harald Kapp]

5 W each LED or 5 W for the whole assembly?
5 W per LED is 60 W per assembly, possibly too hot.
5 W per assembly is ~ 0.4 W per LED and most likely no issue. Looks like this is what you got.
Give it a try and see what happens.

Note that the power dissipation is concentrated on 12 very small local spots (aka LEDs). This will lead to local heating of the board and the LEDs. To ensure longevity you should provide a means of cooling. For example mount the assembly with its back onto a heatsink. Oherwise you risk a faulire of the LEDs even without the foam melting.

 

[Crafts4Me]

hi
i think the entire assembly is 5w since it says power 5w
shall i poke holes in the cover?

 

[Crafts4Me]

i dont have access to a heat sink
this is for a Holiday decoration to be used 2 days a year
shall i line the mounting with some rocks? shall i poke holes into the cover?

 

[Alec_t]

Why are you using spray foam insulation? Would something less flammable (e.g. mineral wool, glass fibre) be ok instead?

 

[Crafts4Me]

i built the display out of spray foam to be a mountain the mountain is built, i matched and wired the lights already i wanted to mount the lights into the mountaintop

 

[bertus]

Hello,

The heatsink can simply be a metal plate where you mount the led assembly on.
There are 3 little holes in the led assembly to screw the led assembly to the plate.
The thicker the plate the more efficient the cooling will be.

Bertus

 

[Crafts4Me]

any metal plate? i am a crafter not an electrician. can some stones be ok? what other material can i use between the leds and the foam?

 

[bertus]

Hello,

Stone is an isolating material.
Metal like copper, iron or aluminium will conduct heat.

Bertus

 

[Crafts4Me]

do i want to conduct heat? i am confused sorry
other option, my lights are menat to be inside plexiglass cases with the light at the bottom shining in base of foam
maybe i can put the lights on top to shine down touching the plexiglass but the back metal plate will be open to the air

 

[Delta Prime]

do i want to conduct heat?

Yes. you want to conduct heat away or dissipate heat from the LED.

any metal plate?

Yes,.The thicker the better.
Remember, you’re dealing with an insulation foam that contain very low conductivity gases, trapped within the plastic that reduce heat transfer by conduction & because this is on a microscopic scale - they’re so small that they eliminate heat transfer by convection. These spray on foams do not melt with heat.They just burn…at a specific temperature in general At 180°F they will catch fire.
Could you take some photos of your project please? You have a great imagination. I have to see this…

 

[Crafts4Me]

hi
i am sorry but i really dont undertsand electricity well enough as i am just a hobbyist and i have creative ideas. i mounted the lights on the top instead of inside the foam. i will send photos when its all done
can i cover these lights with a sparce layer of cotton fluff or that will catch fire?

 

[Martaine2005]

Don’t worry about using spray foam with a total of 5 Watts. Nothing is going to happen.

 

[Crafts4Me]

hi
to simulate smoke i want to add cotton fluff around the leds can i?

 

[Martaine2005]

Of course you can.
To put your mind at ease, power the LEDs on the kitchen table and put the cotton fluff on top. You’ll soon see that nothing happens.
You can also put your finger on each LED and only feel a little warmth.
If you try this with high power LEDs, you’ll burn your finger. But still not hot enough to ignite spray foam.

 

[Delta Prime]

i will send photos when its all done

Thank you

 

[Crafts4Me]

hi
so i got anxious for nothing?
i can safely mount the leds underneath my light bulb covers into the foam? i have craft HD alumium

 

[poormystic]

Hi
It's good that you checked it all out but your anxiety can settle.
What you're doing is safe.
The comment about heatsinks (to keep the leds cool and make them last longer) don't really apply to this project since you probably won't live more than another few hundred years anyway and you're only using it a couple of days at Christmas.

 

[Crafts4Me]

hi
in the end I mounted the leds on top, covered some of it leaving breathing room with white fluff
it was very effective
thank you
I needed it for just 1 day - this will be for a 1 day a year Holiday. i set a timer to shgut it for a bit to further reduce the worry about overheating

 

[Delta Prime]

my application is on spray foam insulation polyurethane foam (SPF)

When you store it away for next year, there’s a very good chance that Mold and mildew growth on the foams’ surfaces can lead to odor, & structural damage, impacting the foam's durability only because you are repurposing this material for an application that it was never manufactured for .An antimicrobial spray of your choice will help prevent this degradation by inhibiting mold growth on the foam’s surface.