by Reid Welch »
Tue Aug 12, 2008 2:13 pm
Lubrication engineering is my favorite hobby. I grew in the subject when I was a teen in the US Navy,
when I picked up a text book on the topic and got engrossed in the science.
this is a rough draft mini-article composted in post, and it will contain typos and minor gaffes:
Yes, you can make your own graphite grease by mixing powdered or flake graphite into any kind of grease.
Because the graphite will thicken the grease, and because traditional graphite greases are high in graphite content, like 30% by weight,
it is best to use a light bodied grease. Now, Vaseline (petroleum jelly) is really not the best lubricant, but it will serve.
All petroleum products such as petroleum jelly and oils eventually thicken, oxidize, age in bad ways.
Today we have a plethora of synthetic lubricants, and all these are more oily than any natural petroleum oil,
just as bacon grease (never use that) is greasier than petroleum grease.
We don't use animal fats for lubrication today because, while they ARE more oily than petroleum products, animal fats break down into corrosive
acidic components, and eat metal.
Of the vegetable oils, canola oil is a very fine, light-bodied oil, and castor oil is likewise useful as a thicker oil. HOWEVER, vegetable oils
age even less well than petroleum oils when exposed to the air. They won't corrode metal, but they will gum because they all have some tendency to dry,
like linseed oil, which is the most agressively drying of the common veggie oils.
We can note by simple tests what is most oily by rubbing the oil between fingertips.
I've used synthetic oils for decades with good results, various kinds, they all resist age gumming or thickening very well.
3-in-1 Oil is fine, but know that it is a petroleum oil with some aromatic content; it's great for freeing up gummed oil oil,
but itself, will gum in time. Plus, it is not as oily as, say, a light bodied synthetic.
TRI-FLOW is a light synthetic oil we may use safely in place of 3-in1, available pretty much everywhere.
For heavier oil, I favor synthetic motor oil.
Primer: What is grease? Vaseline is not grease. Vaseline is amorphous wax.
Grease is thickened oil; oil thickened usually by incorporation of a metallic soap.
There are various metals which are saponified (made into soaps). Lithium, calcium, sodium, aluminum, etc.
These soaps are not really like soap you wash hands with, no; they are more or less insoluble in water.
However, the soap base of a grease determines in large degree the working properties of the grease.
It is the OIL in a grease that lubricates proper, not the soap-base itself, though the two components work together to an extent.
Perhaps the main desideratum of a grease or oil for our phonographs and other old machines of the like, is age resistance.
Quality petroleum greases and oils contain anti-oxidants which slow the thickening, drying process.
ANY purpose-made oil or grease you choose today will last longer (before gumming) than what they used in the olden days,
3-in-1 may be an exception: it is an antique product, a staple for over a century, and I doubt it has been goosed by modern engineers from its original formula,
but I do not really know.
I prefer synthetics, in general, because they are so time stable and so very slippery. In phonographs, all the lubrication effect comes by what is called
boundary lubrication. In boundary lubrication, oiliness is the great aim, but too, petroleum oils perform fine, other than aging less well than synthetic oils,
and petroleum oil prevents wear just fine, as attested to by the condition of most old talking machines.