[GreenKeys] Grease and Oil

[dmm at lemur.com]

Two questions, one on-topic and one probably off-topic...

Lee writes:
>viscosity has very little to do with "flinging" of modern lubricants.

What does "flinging" mean in this context?  (I may have missed something
earlier in this discussion).

In the heavier machinery with which I tend to work (Linotypes and other
type-casting machines, all engineered 70-110 years ago) the oil lubrication
is almost always total-loss.  Viscosity is quite important for these.
Too thick and it won't get in (extreme case: the mold oils for a
Thompson Type-Caster), too thin and it runs through too quickly and
your bearings are dry by the end of the day.


Don writes:
>my 1942 Packard  runs great on 15W-40 modern oil and it is lubed with 
>modern Lithium  grease.

Since you mention antique cars and grease, perhaps you can shed some
light on a question I have which comes out of that area.

In reseaching greases for my machines, I ran across an interesting
story to the effect that bronze worm gears used in 1933 Pierce-Arrow
rear axles were destroyed by modern EP (Extreme Pressure) additive greases.
I have not been able to confirm this, though; the link is:

http://www.eng-tips.com/viewthread.cfm?qid=124116
there is also an inconclusive discussion related to this on the
Franklin Car FAQ at:
http://www.franklincar.org/FAQ/faq6.htm

Now, there are at least three major types of EP additives that have
been used with greases - early ones based on lead (no longer used)
as well as current ones based on sulfur and on zinc dithiphosphate.

It doesn't take much looking to find that the sulfur-based ones do
interact with copper and its alloys.

This has created a problem for me because it isn't always clear whether
a deeply-buried bearing in one of these machines is bronze, babbitt,
or ball/roller.  I'd hate to have to find out the hard way, because
these are parts no longer stocked even by those few who still have parts.
I like making things well enough, but making replacements for
parts that I ruined because I was dumb isn't high on my list :-)

It is also very difficult now to find a non-EP grease, and if EP whether
it is sulfur or zinc dithiophosphate based.  You can't rely on the packaging 
(often you have to check MSDSs); none of the greases available at, say, 
the local Farm & Fleet are non-EP.  Should anyone be interested, I have
managed to track down several non-EP greases and a couple of non-sulfur EP
greases. 

So, any thoughts on the risks of sulfur-based EP additive greases on bronze
bearings?

My apologies that this query may be getting very off-topic for Greenkeys.
I'm not sure if there are any bronze plain bearings on a Teletype or TTS.

By way of making amends, here is some research that may (or may not) be useful 
in light of the earlier discussion...

3-in-1 Household Oil (red can), as per its MSDS, has a viscosity of 
112 SUS (23.31 cSt) at 100 deg. F (not C).  This puts it at the low end 
of SAE Crankcase 10W or within ISO VG 22.  Its components indicate that it 
is basically a spindle oil plus naptha and citronella.  It makes a 
fine mold oil for the Thompson Type-Caster, but is rather expensive for 
that purpose (you want a drop ever 20 seconds through the sight-feed oiler).  
I've been experimenting with Mobil Velocite No. 10 (22 cSt at 100 deg. F), 
an ISO VG 22 spindle oil, as a replacement.  So far it seems to work well, 
and by the gallon it is 1/4 the price of 3-in-1.


Regards,
David M.
===
Dr. David M. MacMillan  -  dmm at lemur.com

   The first rule of intelligent tinkering is to save all the parts.
       - Paul Ehrlich (1854-1915); Aldo Leopold

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