first thing needed to make a variable speed fan is a fan fitted with
a thermal sensor , there have been a few of these made through out
the years . The fan Im using is one from a power supply, out of a
486 computer ( this should give you some idea of how old this idea
is ) . The thermal sensor is woe full to say the least , with
the fan idling at low rpm , and possibly coming on at around 100deg
? , not the best temp to turn on the rpm I can assure you . So what
to do with these fans ?
thermal sensor , and replace it with a 10k pot .
first picture is of our 10k pot , got mine from Dick Smith , for the
sum of $1.90 . Using a multimeter , just make sure you have the
right two connections to solder to . The second picture , is of the fan after the sensor
was removed , sorry about that , should have gotten a pic with the
sensor in place .
remove the thermal sensor , just use the soldering iron to heat up
the solder joints and pull the sensor out with a pair of needle nose
pliers . You can see that Ive melted a bit of the plastic with the
soldering iron , this is ok .
What we do
now is solder in two leads , which will then be soldered to the pot
are two pictures showing you how simple it is , you only need basic
soldering skills to do this . Just make sure the ends of the wire
have been tined ( soldered ) put the wire in place and placing the
soldering iron in from the hole the lead is soldered in place . Dont
use to much solder , you dont need it , and you dont want to short
the joint , as that would make the pot next to useless . ( constant
full speed )
an appropriate sized hole for the pot in the side cover , I now have
a variable speed fan in my side cover . So with a little planning
there is no reason why every 80mm fan in your case could not be of
the variable speed kind . Full power on those warm days and backed
of for those Brrrrr winter days , when the slightest breeze sends a
cold shiver down your spine . Peter at NucleusComputer has a few of
these fans left , check out there web site here
And there is no reason what so ever
that you could not do the same thing with the Thermaltake Smart case
fan , it pumps out about double the AMPs , but I think that the 10k
pot should still be OK ? at $1.90 its not going to break the bank .
Just remove the thermal sensor , solder on new leads , and connect
to the pot , and you have the speed you want at your finger tips .