Fan bearing lubricant was Re: WD-40 (again)

[drlegendre .]

Ok, so there's an annular groove cut mid-way along the length of the shaft.
That might well be for retention of lubricant. You'll have to forgive my
assumptions about low RPM operation - I took these to be the typical
'Muffin' type fans, that run about 600 RPM.

This is a long-shot, but does the groove in the shaft communicate with a
passage in the bearing, by any chance? Just wondering if there's a wicking
type oiling system in the design, as seen in larger electric motors. If
there's no passage for lube, then I'd stick with the suggestion to use a
light-bodied grease like Phil's and make sure to pack the groove full of
it. But again, there's no harm in using a medium-body motor oil, like 30W
or 10W-40. It's not as if it's going to be in 24/7/365 service, eh?

What's the diameter of the shaft, btw? 1/4" or less? Got any pics of the
parts?

On Sun, Apr 17, 2016 at 8:43 PM, Noel Chiappa <jnc at mercury.lcs.mit.edu>
wrote:

>     > From: drlegendre
>
>     > If they use sleeve bearings, take a close look at the material.. does
>     > it have the sintered look of oil-impregnated bronze (Oilite)?
>
> It looks like copper, actually; it's quite reddish. (The central pin seems
> to
> be steel of some sort.) But I'm not familiar with Oilite, so I can't say
> for
> sure.
>
>     > Are there channels in the bearing to allow the distribution or
>     > retention of grease?
>
> There's a section of reduced diameter in the center of the pin; the ends
> are
> full diameter, with no grooves of any kind. The sleeve is a plain cylinder.
>
>     > Those fans tend to run at pretty low RPM
>
> Not these. They are doing very high RPM indeed.
>
>         Noel
>