What material do I use to make the filter? If I call Directron or
browse the website, what do I look for?
It depends on how you want to mount it, how thick it can be,
what level of filtration you want/need, and how much airflow
reduction vs size you can accept. There are many creative
ways to make a filter, even taking a piece of heavy gauge
wire and shaping it like a frame with loops in the end would
work to hold down a panel, or for the front you might add
adhesive backed strips so the assembly is same thickness as
the gap between bezel internal bracing and the case metal
front.
The typical black plastic snap-on type filters meant to be
screwed to a fan frame could have any very thin material cut
to size but typically come with the black material which
could be a reasonable compromise except it would need be
pretty large to lower the flow reduction.
You might get some ideas just browsing your local hardware
store, furnance or air conditioner filters. Even a
car/other automobile air intake filter (probably the pleated
flat type, not round like found more often on old carb'd
engines).
Another option is the woven metal mesh filters, somewhat
like this,
http://www.com-tra.de/img/p/mesh_filter_sz.jpg
though I've seen similar that weren't really mesh, were just
a cheaper less effective single plane of screening or just
sheet metal that was perforated. A true mesh will filter
better without restricting airflow as much, typically less
restriction than a foam or paper filter too (given same
filter area) but may let more fine dust particles through.
I am looking for a simple way to improve things, not shoot for
perfection because this is my machine and I can live with the defects.
Simple can depend on the case, how inventive or practiced
you are at similar odd DIY projects, what your local
hardware store has, and how you define "simple"- the
simplest is to just buy a room air cleaner or continue to
clean out the heatsink every few months.
I will look for that at Home Depot.
With a custom filter it'll have to be on a case by case
basis. It could be that you'd need to increase the opening
in the metal wall on the front, that it didn't restrict
airflow too much previously, but did some- and this added to
the reduction from the filter material is too much, or
rather, too much to keep sufficient flow unless you used
loud fans. Plus, goal is still to keep front intake rate
similar to rear exhaust so the other case gaps, seams, etc,
don't intake unfiltered air... but if you have a fan on the
front, it will still reduce dust buildup inside if not
eliminating it.
You mentioned previously that your removable drives also
have fans... could be another entry point for dust if
unfiltered.
I'd start by taking off the case front bezel and determining
how you want to go about getting a filter on and off later
for cleaning or replacement. Next determine if the case
metal is restricting airflow a lot, especially consider this
if the front intake fan is on a stamped metal grill.
Measure the space for a filter and compare to readily
available filter material. If you can fit a very large
filter and position it a centimeter or more away from the
case metal (like with adhesive backed foam I'd mentioned
previously) it will impede airflow far less and/or require
cleaning or replacement far less often, and/or you can
choose a finer material to trap more dust.
If it's pleated you may need to build a solid wall in it, to
seal... somewhat like an automotive filter does around the
border. Cut to size and take caulking a pass at a time to
build up a flat(er) area to affix the adhesive backed foam.
I should mention I'd always meant for the adhesive backing
on this to adhere to the filter panel, not the case, and
then be held in place by friction... as the adhesive backed
foam is open cell so it will compress quite a bit, is sized
so it's slightly thicker than the available space between
the back supports of the case bezel and the metal wall.
On such a project it's hardware to describe than to do, once
you see what you're working with behind the case bezel.
