layer of foam between radiator and fans?

[new2h20cool]

I am about to build my first water cooled system and have been watching only about 1,000 different videos on the topic to try and learn how to build it most effectively.  One of the videos indicated that there maybe an inefficient airflow push/pull due to the gap between the fan and the radiator. My understanding is the gap is created due to the fans and radiators not being perfectly flat.  I was wonder if anyone has placed a thin layer of foam (1 mm or 2 mm) on the edges of the fan to create a better seal between the radiator and the fans.

[vf1000ride]

Some of the newer Noctua fans come with a silicone rubber gasket to do just that.  You can also buy premade ones in either foam or rubber.

https://modmymods.com/fans-accessories/fan-gaskets.html

[RejZoR]

You don't need a rubber seal. You can do a gasket of similar shape yourself using thin plastic. Like the transparent one found in toys packaging or motherboard covers inside the cardboard box. All you need is scissors and a marker. And something to puncture the holes for the screws. Make it big enough so it covers the radiator gaps between fan and radiator and that's it. I know this can be done and it works great because I use BeQuiet SilentWings 3 on my AiO and these fans have anti vibration corners which work great on case, but with AiO they leave huge gaps in corners where pressure leaks instead of forcing air through the fin stack. You could even get away with some thin cardboard if you don't have any plastic around to cut to that shape. Or you can just buy it. But in my case, store bought ones don't create a good seal around corners and I cut it specifically to fit exactly around the middle round fan section for SilentWings 3.

 

Here's an image of SilentWings 3 to better understand what I mean. There is literally a ring surrounding fan blades and I needed to create a seal that fits that. All these pre-made gaskets would still have huge gaps in corners as well as everywhere else. With thin plastic, I cut it precisely to tightly fit right around the middle ring section and extend slightly outside the entire fan frame to form a nice seal on the radiator (single 120mm, if the radiator was dual or triple I'd just do it for multi fans the same way).

[Lipe123]

My rads came with a thin foam backing sticker when I bought them ages ago.

 

However I really can't see it being that much of an issue, that tiny gap is less than the gap between the radiator fins.

My rads are perfectly flat and the fans are completely flush with them.

 

Overthinking the 1% tiny details. The type of fan you choose makes 100% more difference than a 1mm gap between the edges of the rad.

[00RaZoR11]

On 6/19/2020 at 10:26 PM, new2h20cool said:

I am about to build my first water cooled system and have been watching only about 1,000 different videos on the topic to try and learn how to build it most effectively.  One of the videos indicated that there maybe an inefficient airflow push/pull due to the gap between the fan and the radiator. My understanding is the gap is created due to the fans and radiators not being perfectly flat.  I was wonder if anyone has placed a thin layer of foam (1 mm or 2 mm) on the edges of the fan to create a better seal between the radiator and the fans.

Unless it's fun for you to make it absolutely perfect, don't worry about this.