David Harris wrote:

Does anyone know what this is /likely/ to be:

http://www.roksan.co.uk/roksan/roksanpage.php?pageno=6#

3in1, some grade of motor oil, some hybrid concoction?

I never found out what the right oil for a Garrard 401
was.
As the bearing is similar to a Roksan, according to the
pdf on that page,
then I guess the oil will be about right too.
I thought for a plain spindle on top of a ball-bearing,
something heavy like EP90 gear oil would be best.


I went the other way with my Thorens deck, and I used
sewing machine oil. Yes, I did need to top it up fairly
regularly, but it did *seem* to give less bearing noise
off the platter than a heavier oil.

I also tried PTFE spray once, but wasn't so keen.

Yes, it *is* actually important to use the right kind of
oil. The lubrication requirements of ball and plain bearings
are different, so most car or bike oils are unsuitable. The
problem here is that it's an odd application in a domestic
context. That's why the retail price is high.

Too thick, or too slippy like PTFE, STP, or molybdenum
disulphide, and the balls will skate. The surface of the oil
will be wavy so it can be a choppy ride. If a ball catches
up with its own bow wave it may briefly lock and judder.
Pressure can be great enough to crack the casing, although
not at turntable speeds.

Too runny and it won't maintain a film.

If it absorbs moisture then corrosion-erosion will lead to
early failure.

You need a thin or medium single-grade, thixotropic (or
"clingy"), water repellent, corrosion-inhibiting machine
oil, I would think. Best option, unless you already have
some of the right kind of oil, is the recommended oil from
the manufacturer, if you can get it. Maybe expensive for the
amount you get, but you'll only ever need a few drops. Share
with friends.

A plain bearing would be quieter but an oil pump would be a
problem, I suppose.

Ian