"Feathered Edge™ for Lower Noise"?

[Intraveinous]

Hmm... I got a couple of the Comair Rotron Major DC 235CFM fans from BGMicro last week, and I've been looking at it and wondering some things. On the Comair Rotron site for that fan: http://www.comairrotron.com/dcfans/MajorDC.htm
It has the line "Feathered Edge™ for Lower Noise". I assume the "Feathered Edge" is the notches cut out of the fan blades.
Anyway, what I was wondering is this: Has anyone done so, or does anyone know if it would work, to cut notches, or to "Feather the Edge" of say, a Delta 80mm 68CFM, to lower the noise?
Hmmm...
Anyway
Thanks in advance for replies, I've really been impressed with these forums, doesn't seem to get quite as [H]ot if you know what I mean... :D
John

[The Overclocker]

yeh these forums are great, i have registered with others but they arnt any good so i end up forgetting my password, i dont know about your fan idea, if they do lower noise thay could also lower cfm, a better idea would be runni9ng the fan at 7 volts

[Intraveinous]

Yeah, I have them at 7volts, just was something I wondered about... Hmmm, wasn't there someone who used to work with/for Comair Rotron quite a bit around here?
BTW, to everyone who's getting these for 8.50 plus shipping, we're gettin one he11 of a deal! I found em in a catalog for upwards of $60 in small (1-9) quantities.
John

[The Overclocker]

i can get then with free shipping, deltas are easy to get hold of in the uk

[Intraveinous]

Not the deltas, the Comair Rotron Major DC 235CFM monsters.
:D
Hmmm.... Dare I order a couple of the 500 CFM 10 inchers???
hehe
John

[Pounder2000]

speaking of that offer at BGMicro, they've sold out just as i was about to order 1!!!!

they said they had got 2480 in stock and were not getting anymore.

so here is my request to anyone with a spare one or (unlikely) an unwanted one, please get in touch because i an desperate for this fan but not desperate enough to pay $70 + shipping havnt got the money... :(

i'll pay shipping as im in the UK.

can anyone help?

[Intraveinous]

Pounder:
YGPM
John

[Pounder2000]

yeah, im on ICQ aswell

[Intraveinous]

I'm @ Work, so no ICQ...
John

[BillA]

once saw a post where a fellow took an Xacto knife (razor blade) and very fine files and sandpaper to his fans;
and alleged appreciably lower noise due to the removal of mold parting lines, burrs, and general streamlining

seemed reasonable, but he had no hard numbers
if anyone gets into this, please post the results
(I hate noise)

be cool

[RedDeathDrinker]

The effort involved probably outweighs the slight gains in quietness acheived. The noise is the moving air, so reducing the noise generally means reducing the airflow. I compromise, I turn the volume up............

[BillA]

well .... not quite

the noise is from turbulence, which has several sources
one (small) part of which are the assorted "imperfections" from etc.

yes, I too believe the net noise reduction might be small - but I don't know this because I've not done it
the net air flow should (very slightly) increase - the blades are not being reshaped, just cleaned up along with the hub, struts, etc.

be cool