Discussion in 'General Hardware' started by Astyanax, Apr 2, 2021.
Does not that removes OIL?
Number 1 is silly. (are you seriously claiming they start off with NO lubrication) Sheesh.
Number 2 is silly as it is based on the silliness of number one.
Number 3 is silly as you should only be oiling the shaft.
Nothing in your post is based on any fact.
It would not be surprising if after cleaning your dirty fan and oiling it, it ran faster. This has to be the first time I've read anyone advocating for HIGHER friction to slow a fan down...
Sewing machine oil is the best for lubing the shaft on a fan and this is known by almost everyone.... almost.
WD40 is a water dispersant, I have stupidly used it in the past on a squeaky fan and it worked for a little while but ultimately ended up squeaking again...
WD40 breaks down grease and oil.
they are shipped with grease (lithium or otherwise)
the grease is more viscous than oil so the max rpm is lower.
You're going senile old man, go away.
I recently WD40'd my living room window mechanism that was getting stiff, which turned out to be a mistake as now with the slightest gust of wind it rips the window wide open and almost off the hinges
Too much WD40 xD
It was very stiff
Bearings use a suitable lubricant based on application and conditions:
(a computer fan would be very low radial and axial load, moderate rotation speed application in generally clean conditions)
This video is only relevant to ball bearings.
loads are different with sleeve/rifle/fdb and more so if they are installed as bottom/top intake/exhaust.
in fdb/rifle the grease pumping effect also maintains balance of the hub, iirc the skf website was where i read that lithium grease was best for bushing type (sleeve) bearings.
Correction: video is relevant to roller type bearings in general. Sliding contact bearings like sleeve bearings are different, yes, but same considerations apply.
As a mechanical engineer I would say a computer fan is such a simple application that choice of lubricant is near arbitrary.
In general grease is preferred but as long as there is an appropriate amount of a lubricant present that is not of too high viscosity (due to low loads) you're good.
As defined in the video grease = 85 % mineral oil + 15 % soap (stiffener) like lithium.
When we talk about commercial "oils" like WD40 we are not talking about 100 % mineral oil.
(Actual composition of WD40 is apparently a secret but it's most likely baby oil and vaseline + additives, so closer to "grease" than "oil").
would never use wd40 for fans.
What i used is a mineral oil without the stiffener, ended up making the fan noisier through higher air flow/faster rotations. , i plan to get some superlube or lithium grease and redo the lubing (fan in question, bitfenix spectre pro), or just replacing with a few corsair ML's and not have to worry about it for a long time.
What is your thoughts on greases with solid lubricants? (Graphite and molybdenum, etc)
Not really an expert on those but:
"Solid lubricants are needed for lubrication under extreme circumstances where tribological contact bearing surfaces still need to be efficiently separated..."
Solid Lubricant - an overview | ScienceDirect Topics
In other words as far as I can tell applicable to heavy machinery in harsh conditions where maintaining proper lubrication is difficult or servicing is not possible or feasible.
So as far as computer fans go:
- at the very least complete overkill
- may not work properly due to low radial load
-> as a result might even inhibit rotation due to solid particles
The SKF video actually showed a similar concept with grease: pressure applied from the roller element "squeezes" the lubricant particles out from the mineral oil suspension.
In turn if not enough pressure is applied, the lubricant actually does not work, especially so if talking about solid lubricants.
Choice of lubricant depends on application and especially radial load and external conditions.
PS: I work for a company that manufactures medium-heavy machinery. All we ever use is "regular" bearing grease in our machines.
PPS: my wording earlier was a bit hasty:
choice of lubricant is arbitrary in the sense we are talking about a simple application with computer fans, but that does not mean an extreme high-end, heavy duty lube would be better than more conventional lubes or necessarily even work.
Follow up: examples of applications from the SKF link:
Trunnion bearings on rotating drums
Support and thrust rollers on rotary kilns and dryers
Bucket wheel excavators
Slewing ring bearings
High pressure roller mills
so a bit rougher than computer fans
(and indeed meant particularly for high load, low speed).
I'd like to add:
Running temperature of the bearing figures when choosing the grease/oil formulation.
It will be stiffer at first but loosen up as temp rises.
With a computer fan this 'should' be less of a consideration (due to lower heat generation) but the size of the fan and its running speed will also change the required viscosity.
ie smaller will likely be hotter due to running faster in most applications.
Utimately the result will speak for itself but...
My point is to run the fan for a long period in a typical environment before deciding which formulation to settle on.
A PWM (or any speed controlled) fan with a well sealed bearing can permit a high quality lighter grease/oil as long as it doesnt promote vibration.
This will reduce power needed to drive the fan at any speed. It will not run away fast because the speed is controlled via PWM (stated for completion).
But if the fan is later run as none PWM it can run too fast.
Type of use applies.
So graphene and molybdenum are definitey overkill
Right, so too thick can be a bad idea, but particle loading can also be a problem for low power motors.
Best to stick with the super lube then, its been reported to work long term on pc fans.
Some fan vendors are better than others where motor heat is concerned, on a nzxt 140mm fan feels to be atleast 37c where as the bitfenix is below body temperature. when touching the blade hubs front.
Vendors like arctic practically shot out their 10c lower (than other) motor temperatures citing it as a win for longetivity.
Oil spitting tends to be a common problem with sleeve bearings due to the way they don't plug up on both sides under.
theres an rubber o-ring on the backside where you place the C clip to hold it in the sleeve, but on the front the rubber ring can pull away from the bearing enough during rotation to have the oil traverse the blades and leave a nice circle around the fan frame.
I believe it to be a symptom of cheap, or bad design since most fans don't allow this sort of give in the first place.
This was also a well known issue with msi twin frozr's between 2010 and 2015.
If you guys want my take, this is what I would do, regardless of sleeve or roller bearing:
apply a thin film of bearing / axle / multipurpose grease on roller elements or sleeve.
However if all you have is eg. WD40 it's a lot better than nothing.
Any synthetic vaseline should work just as well.
Having said that if the fan is already rattling the bearing is worn and about to fail.
You don't fix a whining wheel bearing on a car either by lubing it, you replace it.
In other words, consider what's worth the effort.
Yeah, both the top mounted FS series 200mm nzxt fans went this way in my phantom 820, i probably could have prevented it but nzxt actually used a high tension sticker across the rubber cap so i actually assumed wrongly that the FS's had no access to the bearing without drilling into it, since i couldn't feel the usual "give" that the rubber cap allows (i based this on other nzxt FS/FN fans that also don't have a cap.)
The fan controller itself decided to fail after i turned them both off (apparently can occur on low end/cheap DC fan controllers when you do this)
I have an FZ 200mm mounted on top that i had sitting around now, but installed in the same way as the FS its actually vibrating into the chassis and introducing an odd harmonic along with the TY-143 mounted in the center of my Silver Arrow, I'm going to just dump the top exhausts and the silver arrow at the next opportunity for a liquid freezer II 280 or 360, presently undecided, i just need to find a compatible backplate for x58 since theres no official support from Arctic, but i've seen a number of reviews on amazon that it works with the 115x standoffs so long as a compatible backplate is used (it might actually work with the 2011 standoffs if i use the 1366 mounting plate sold be thermalright for the original ultra extremes)
Yeah, so mainly if they are rpm monitored fans and you notice them running slower than usual, they could benefit from a cleaning and regreasing, though in some cases if its slightly humming or visibly dipping in speed every few rotations it could just be dust thickening the grease and causing the bearing to sit off tilt.
Well last night my last original 120mm Antec 3 speed fan started to do a very slight tick tick tick sound.... funny that it happens after commenting in this thread... lol
I've oiled fans before and found it a big help but only the smallest amount of oil is needed, oils can degrade and go tacky but ive found oil from wd40 and fine oil from my hair clippers do a great job, although if the sticker covering the bearing are left intact most modern products should be good until they reach the end of there natural life