On Thu, 11 Sep 2014 06:11:07 -0700 (PDT), Phil Allison
wrote:

Jeff Liebermann wrote:
The bearing/bushing burnout theory is also interesting. This
particular fan, Mechatronics Model F8025H12B2 12v 0.145A claims to
have ball bearings inside. I'm not going to take it apart because I
know that it doesn't have ball bearings. It uses bushings like all
such cheap PS fans.

Peal of the paper label and take a look sometime.
Brushless DC fans mostly use ball bearings.
... Phil

I've taken quite a few power supply and CPU fans apart in order to
clean off the ring of tar (formerly oil) that accumulates on the rotor
shaft and re-lubricate the fan. Usually, the shaft fits into what
looks like a sintered bronze sleeve. I don't recall seeing ball
bearings on the smaller (80mm or less) but may have been looking at
fans with both a sleeve and a ball bearing (1B1S), as described below
at bottom of page:

Anatomy of Computer Fans
http://www.hardwaresecrets.com/printpage/Anatomy-of-Computer-Fans/1039

Ball vs. Sleeve: A Comparison In Bearing Performance
http://www.nmbtc.com/fans/white-papers/fans_ball_vs_sleeve/

Fan Design (review) including info on bearing types:
http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/4534-glacialtech-igloo-5750-silent-cpu-cooler-review-5.html

Let me see if I can dream up some other ways to destroy this fan with
compressed air before I dissect it. Stay tuned.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558