SPECIAL NOTE: The following information relates specifically to the moving parts in the spoolbox and transmission of an ordinary 88-note player piano.

   A recent posting in the Mechanical Music Digest concerning lubricants for the metal parts in player pianos caused a number of people to offer their opinions. Within a week, it became realtively clear that there was very little 'hard' data on the topic. Typically, those who engaged in the conversation provided information about either their own personal experiences or the opinions of those in related fields, such as music boxes and clocks. While these opinions had some value, they didn't get to the heart of the matter, i.e., what constitutes a good lubricant?

   Regarding lubricants for metal-to-metal parts in player pianos, a number of the original player piano service manuals recommend 'a light oil', 'tallow', or 'grease'. However, most of these manuals were written 90-110 years ago and 'time' has proven that such lubricants eventually become problematic. Service manuals written for modern player pianos made between the late 1950's and the 1980's, recommend "oil" or "vaseline". Apparently, the problem with all of these lubricants is that sooner or later they will dry up and become 'gummy'.

   After exchanging a number of emails with a couple of people who were willing to look deeper into the matter, Craig Brougher wrote the following:

The problem of oil congealing has been around forever. Whether gun oil, sewing machine oil, synthetic oil, or anything else like that, it will not be around forever. It's a property of petroleum-based products. Ironically, the organics in engine oil begin the decomposition and its proclivity to get sludgy.

Synthetic oil (so-called) is a petroleum-based oil and isn't 'synthetic" at all. The difference is, they've refined the paraffins out of it but it can still slowly oxidize and evaporate. However, synthetic oil evaporates much slower than regular oil. So-called "synthetic" oil was developed for aircraft engines several generations ago, and just recently 35 years ago was tried in car engines to see if they could see it as premium engine oil. No problem. But engine oil is changed either every year or less, depending on mileage, so it doesn't get the tests we're putting it to.

Ditto ditto with sewing machine oil and gun oil. Some are just slower than others. But there is a solution to it in player piano work and transmissions, at least. It's called Marvel Mystery Oil. Now I always disassemble and clean the transmissions first, but for a long-lasting quickie fix, an oil dispenser loaded with the stuff will quickly take the stickiness out of any kind of oil, and by just lubing your transmissions with it after they've been cleaned up, it seems to last forever. I have players now in service for over 50 years and they still don't need a drop of oil. I can wholeheartedly recommend this stuff. It's a top lube, meaning you add it to the gas. But the fact is, it burns clean, which means it doesn't have the very things in it that causes other oils to congeal! [NOTE: Craig is not suggesting that you mix Marvel Mystery Oil (MMO) with gasoline when using MMO to lubricate parts in a player piano.]

Thanks for the reply. I wasn't actually referring to Tri-Flow. But if it's mineral oil, then it is chemically stable because it has no organic properties left in it, and with a teflon additive it will be perfect. What I was referring to was the general subject to which you replied--"Clock oil and mysteries of WD-40." Granted, mineral oil is still petroleum based, but is a heavy napthenic and very stable. https://en.wikipedia.org/wiki/Marvel_Mystery_Oil

By the way, Tri-Flow sounds like it has the same basic chemical structure as Marvel Mystery Oil. My letter to you here refers to the basic principle behind the lubricant which I was suggesting. The fact that Tri Flow is primarily "mineral oil" means it is more stable than simple refined oil, over time, too. So Tri-Flow has a similar chemical structure plus the additive of a fluorocarbon. Teflon (trade name) is used in space because it doesn't evaporate even in zero vapor pressure. MMO (Marvel Mystery Oil) has tricresyl phosphate instead of teflon, but is also an extreme pressure dry lubricant.