Open or Dense Air Filter?

[Bobendren]

That subject line doesn't do a very good job at explaining at what i'm getting at. Basically I have a choice (i.e i can get this stuff for free )between thin dense foam or a thicker less dense foam to use as air filters. The thinner will probably be able to catch smaller pieces of dust but allow more through, while the thicker one will catch more dust but let smaller particles through.

So which is the better solution? Or should I be looking at car type pleated filters instead?

Here are some pics:


The thin dense foam.



The thick less dense foam.



Close up of the two (standard sized case screw and AA battery for comparation)

[mrzed]

If I had to choose, I would use the thinner one, but if you can manage it, a pleated filter will certainly work better (albeit with more restriction).

Much depends on the dust challenge you face and how often you want to clean out your computer. Personally, I like the idea of pleated filters, but have never got around to it. As a result, I clean out the accumulated dust every few months (or should).

[IsaacKuo]

Why not both? I notice that a lot of air conditioner filters feature more than one layer. First is the coarse layer, so it can catch big stuff and keep it from prematurely clogging up the finer layer behind it.

In any case, I'd make sure the filter area is much larger than the area of fan behind it. Pleating is the obvious way to acheive this, but I imagine it would be difficult to fold up this foam stuff neatly.

[jaganath]

Why not both? I notice that a lot of air conditioner filters feature more than one layer. First is the coarse layer, so it can catch big stuff and keep it from prematurely clogging up the finer layer behind it.

A/C units tend to have more powerful fans than are available or appropriate for a silent PC setup. They also tend not to be very quiet. Using both foams in series will be hideously restrictive and reduce airflow hugely. If I had to choose I'd go with the thinner foam, but really if your dust problem is that bad you should focus on eliminating the source (ie carpets/pets/smoking) or at least keep them out of the immediate vicinity of your PC.

[monkiman]

but really if your dust problem is that bad you should focus on eliminating the source (ie carpets/pets/smoking)

I think my wife might have issues with me "eliminating" our pets

[simeli]

cleaning out really small dust particles out of a computer is difficult at best. so i'd look into a solution that does not even get it in there.

first stop on this would be as mentionned, eliminate the source of dust

there are humidifiers that can ionize (sounds dangerous but is not ) water molecules before sending them airborne. these molecules will attract dust particles which will then fall. anything on the ground is better than airborne.

try keeping the computer case higher up in the room. desk is better than underneath, dust concentration is higher closer to the ground.

make sure that your case is under positive pressure, that way you can force all the air through a filter easily. (test with a lit cigarette).

filterwise, oiled car or motorcycle filters work best. however, most often modding is required. as mentionned, any filter causes flow impendance, the result being that the system gets noisier.

the thicker of the two foams is better suited for filtering purposes as it will fill more gradually. the thinner one will be full just on the surface within a couple weeks. it would probably be best to use the two together. but every bit helps. watch the temperatures in the system after installing the filter, especially now in summer...

[Bluefront]

That two-layer filter approach works pretty well, but still requires frequent maintence to prevent clogging when using foam as a filter.

Pleated filters designed for air filtration work the best, but all require modification to the computer to work/fit. Here's a rear case filter setup I made recently, that just ftis over a rear case fan mounted externally. The fan is blowing into the case (positive pressure). This computer runs clean with that filter(out of a Hamilton beach small home air filter device}.

[breunor]

If you have the clearance behind the case for it, you can make a wire box and wrap it with the foam. It can attach to the normal fan opening, but there is much more surface area for air to be pulled through the foam to help with flow. Just make sure your exhaust is vented away from this of course.