Redneck Way Oil

[J Tiers]

Just be sure it's non-EP oil- the chlorine in EP will attack any brass in the machine.

Hmmm....."attacking" and "destroying" are two different things.

I have heard the comment about oils in the past, but have never seen any of the resulting damage. What actually happens to the brass or bronze? I am aware that copper is discolored by sulfur and sulfur compounds. Use of "liver of sulfur" is a common way to give a good patina on copper. That reaction seems to be somewhat self-limiting, however, it does not eat away at the copper.

Similarly, people also say to be sure never to let lye (i.e. Purple cleaner) touch aluminum, citing fears of it doing damage. However, in my experience it takes a lot of lye to do any visible damage beyond a slight etching. And that reaction is definitely not self-limiting, it will go until the lye is exhausted

The amount of sulfur in oil s small, and the amount which can react is likely smaller. So, how much actual damage does it do? What is the nature of the damage?

[Willy]

In order for the sulfur EP additives to do any meaningful damage other than discoloring the metal, high pressures need to be present in addition to heat.
I've seen EP fortified gear oils used in applications that used brass or bronze worm wheels in conjunction with a steel worm gear, the loads were light and the temps where at room temperature and cooler. After several years of use only a slight discoloring could be observed on the bronze worm wheel and no wear was evident.

Under high loads, high temps, and extreme pressures the active sulfurs in some additives will combine with the copper in yellow metals to form copper sulfide and in extreme cases copper disulfied. These will form crystals that are very hard and abrasive and will eat yellow metal for breakfast.

[nickel-city-fab]

Under high loads, high temps, and extreme pressures the active sulfurs in some additives will combine with the copper in yellow metals to form copper sulfide and in extreme cases copper disulfied. These will form crystals that are very hard and abrasive and will eat yellow metal for breakfast.

Yup, I've seen older transmissions destroyed that way -- the synchros and bushings were often yellow metal. Wrong oil or additives and you would find the remains of the synchros and bushings down in the bottom of the sump.

[Bob Engelhardt]

...
However, in my experience it takes a lot of lye to do any visible damage beyond a slight etching.
...

More than the amount of lye, the concentration of the lye is key. The concentration in a household cleaner like Purple (Power?) is low. A saturated solution (about 1M, I think) is something else entirely.

[J Tiers]

More than the amount of lye, the concentration of the lye is key. The concentration in a household cleaner like Purple (Power?) is low. A saturated solution (about 1M, I think) is something else entirely.

Well, that is the "amount", the molecules/ml and the ml present. The total amount of reactive substance available.

Which is exactly why I am asking the following (as before) :

What actually happens to the brass or bronze? (What is the nature of the damage?)

how much actual damage does it do?

We have one contestant who says that it is not an issue unless there is a lot of stress. What constitutes "a lot of stress" is not defined. And the process is not really indicated either. "Something" is stated to "eat the material for lunch".

But, it seems even from that statement, that the process is the copper alloy forming a compound (with the oil constituent) along the grain boundaries, and the metal then cracking along weakened grain boundaries. If it were forming an abrasive out of the metal, that would directly remove metal, which is essentially what seems to be claimed as the failure. The alleged abrasive nature would be less important than the basic removal of metal by cracking.

Perhaps the real issue is that stresses in highly loaded assemblies are sufficient to cause stress corrosion cracking, presumably along grain boundaries, maybe elsewhere.

That would agree with light loads not causing an issue, as well as the formation of the so-called "hard crystals". And the issue would not be the action of the hard crystals, but the fact that the material of the "hard crystals" was actually removed from the damaged metal.

[The Metal Butcher]

Here we go again with another 100 post thread on way oil.

Halfway! You all are damn psychics haha.

[Doozer]

EP attack must have been a fair size issue.
I am into old International trucks of the 1950s.
Every specification part of the manuals that
I have, calls for 50 weight engine oil for the
transmission. (which is the same weight as
90 weight gear oil, not sure why that is, but
it is).

--Doozer

[Doozer]

Well, that is the "amount", the molecules/ml and the ml present. The total amount of reactive substance available.

Which is exactly why I am asking the following (as before) :

What actually happens to the brass or bronze? (What is the nature of the damage?)

how much actual damage does it do?

We have one contestant who says that it is not an issue unless there is a lot of stress. What constitutes "a lot of stress" is not defined. And the process is not really indicated either. "Something" is stated to "eat the material for lunch".

But, it seems even from that statement, that the process is the copper alloy forming a compound (with the oil constituent) along the grain boundaries, and the metal then cracking along weakened grain boundaries. If it were forming an abrasive out of the metal, that would directly remove metal, which is essentially what seems to be claimed as the failure. The alleged abrasive nature would be less important than the basic removal of metal by cracking.

Perhaps the real issue is that stresses in highly loaded assemblies are sufficient to cause stress corrosion cracking, presumably along grain boundaries, maybe elsewhere.

That would agree with light loads not causing an issue, as well as the formation of the so-called "hard crystals". And the issue would not be the action of the hard crystals, but the fact that the material of the "hard crystals" was actually removed from the damaged metal.

Jerry is out there at the end of the pier and jumping in the water.
Trying to reel in the unknowns and under quantitative statements.
I get it. Really I do. I think our brains might think a bit alike. Scary.
But fact being, many times the unknowns are too difficult or costly
to quantify, people go with blanket statements of disqualification.
Take asbestos for example. There is white asbestos, yellow asbestos
and brown asbestos. They come from different mines in different
parts of the world. Only one form of asbestos has the hook fibers
that stick to your lungs. BUT because when refined into the end
product, be it brake shoes or cement fiber house siding, it is difficult
to know exactly what variety of asbestos the product was made from.
So the influencers of the world have categorized ALL asbestos as
being dangerous, even though it is not so. This because of lack
of the ability to maintain a chain of certification data as to which
variety of asbestos was used. It is EASIER to condemn all asbestos
as dangerous than clearly delineate and identify it properly.
Same thing happened with EP gear oils. It is EASIER to say all
of it is bad for copper based alloys than it is to categorize and
convey which is harmful or not. Sad but true. It is EASIER to create
false information than it is to convey accurate information.
It is Easier to remember what is wrong than to remember what
is right. Sad and lazy state of affairs we have.


--Doozer

[Willy]

It is true, not all EP additives are deadly to yellow metals under all conditions.
This is a very complex issue and one that some could write a book on, a subject I consider a very intriguing topic. I have some of those books and refer to them as the need arises, which isn't that often anymore.
One could do a bit of research on the subject as the need arises as there is so much product information from all of the major lubricant and additive manufactures, never mind major component OEMs. We do live in an information rich age, it's literally at our finger tips if we care to look. No more hunkering over a book late at night at the library.

In that vein since I'm up to my keester in work I had not anticipated I'll do a simple cut and paste hoping to shed a little insight into the mysteries surrounding EP additives.

From the website, Machinery Lubrication:

Extreme Pressure Additives in Gear Oils

Jeremy Wright, Noria Corporation
In most slow, highly loaded, geared applications, there exists a lubricating condition that is typical for most failures due to adhesive wear. This condition is known as a boundary condition. In a boundary condition, there is no separation of the interacting surfaces. The function of an extreme pressure (EP) additive is to prevent this adhesive wear and protect the components when the lubricating oil can no longer provide the necessary film thickness.

How It Works
EP additives are polar molecules. Imagine a molecule having a head and a tail. The head of the molecule is attracted to the metal surface, while the tail is compatible with the lubricant carrier (oiliofilic). As the conditions under which metal-to metal interactions become more severe due to higher temperatures and pressures (greater loads), the lubricant film becomes more stressed. The distance between the metal surfaces has decreased to the point where rubbing is occurring and welding (adhesion) becomes highly likely.
Traditional boundary lubrication additives do not remain on the metal surface and cannot prevent the increasing friction, wear and damage to the machinery seen under these conditions. Extreme pressure additives are required in order to enable the specific application operating under these conditions to continue.
There are two main types of EP additives, those that are temperature-dependent, and those that are not. The most common temperature-dependent types include boron, chlorine, phosphorus and sulfur. They are activated by reacting with the metal surface when the temperatures are elevated due to the extreme pressure. The chemical reaction between the additive and metal surface is driven by the heat produced from friction.
Much like when you rub your hands together, as the metal surfaces come in contact with one another, there is heat generated by means of friction and pressure. In reacting with the metal surface, these additive types form new compounds such as iron chlorides, iron phosphides and iron sulfides (dependent upon which compound is used). The metal salts produce a chemical (soap-like) film that acts as a barrier to reduce friction, wear and metal scoring, and eliminate the possibility of welding.
The nontemperature-dependent, overbased sulfonate, operates by a different mechanism. It contains a colloidal carbonate salt dispersed within the sulfonate. During the interaction with iron, the colloidal carbonate forms a film that can act as a barrier between metal surfaces, much like the temperature-dependent; however, it does not need the elevated temperatures to start the reaction.
Basically, EP additives serve as your protection from wear when the lubricant itself can no longer separate the working surfaces. You can now breathe a sigh of relief knowing that you have specified a lubricant with EP where it is needed. Or have you?


Limitations of Extreme Pressure Additives

Noria Corporation

Chlorine, potassium-borate and sulfur-phosphorus extreme pressure (EP) additives are primarily used for industrial gear lubricants. These additives are temperature-activated and react with metal asperities to form a sacrificial film. Unfortunately, these types of EP additives have some limitations, such as:
1. They can be detrimental to slow-speed gear applications (less than 10 feet per minute), causing high rates of wear known as “polishing.”
2. Extreme pressure additives like sulfur‑phosphorus types can be “too chemically reactive,” resulting in polishing wear. This type of wear is undesirable because it reduces gear accuracy by wearing away the tooth profiles. In these cases, potassium-borate additives can be used to deposit EP films without a chemical reaction with the metal.
3. The rate of reaction of EP additives is greatest where the gear tooth contact temperatures are highest; therefore, some difficulties are experienced in low-temperature applications when operating temperatures do not become high enough to fully activate the reactive EP agents. The viscosity of the base oil is of extreme importance. Anything that reduces the bulk oil temperature or the flash temperature will reduce the total contact temperature and increase the risk of wear. If the total contact temperature is not at the necessary level, the extreme pressure additive may not react correctly or at the right rate.
4. Solid lubricants such as molybdenum disulfide, graphite or tungsten disulfide are sometimes used when the operating temperatures are too high or low for an oil in which the reaction rate may not be sufficient; however, these solid films have limited wear lives and may not carry the loads necessary for long gear and bearing life.
5. Sulfur-phosphorus EP additives have a high-temperature limit of approximately 95 degrees C. This restricts the temperature range in which these oils can be used.
6. Sulfur-phosphorus EP additives are somewhat corrosive to yellow metals, particularly at temperatures higher than 60 degrees C. Worm gearsets frequently contain phosphor-bronze materials, and it is for this reason that gear oils using sulfur-phosphorus EP additives may not provide satisfactory service in worm gear drives.
7. Depending upon the amount used, sulfur-phosphorus EP additives may not be compatible with oils containing zinc anti-wear (AW) additives. This is why it is not recommended to mix AW gear oils with EP gear oils.
8. Chlorine and borate EP additives may not be fully effective or may cause corrosive conditions where water is present.

There are many more facets to this interesting topic on just that one website alone, however I hope to have offered a bit of insight and possibly whet the appetite for those that find the subject as interesting as I do.

[Willy]

EP attack must have been a fair size issue.
I am into old International trucks of the 1950s.
Every specification part of the manuals that
I have, calls for 50 weight engine oil for the
transmission. (which is the same weight as
90 weight gear oil, not sure why that is, but
it is).

--Doozer

Certain components of the transmissions internals are very likely brass. Most transmission do not require the use of EP additives.. A hypoid differential definitely does as it is a much more difficult component to lubricate due the design of the gears and how they mesh. compared to simple helical or spur gears.

[J Tiers]

Since ways typically do not include copper-bearing or zinc-bearing metals, are typically not extreme pressure situations, and are typically not working at above 60C, the concerns appear to be perhaps over-cautious as applied to mixing up some home-brew way oil from oil and additives.

That might be less true if your machine has an oil pump in the apron and uses way oil in the apron as well as on the ways themselves. Aprons may have copper-bearing materials in them

I'm not planning the use of EP lubricants as an additive, the worst I'd do is probably an ISO68 and Rislone. And I do not have an apron on any of the lathes that has a reservoir etc, so I get to choose the lube for each part.

But Doozer is right. It's interesting, and the "engineering mind" is not typically tuned to accept the "old mechanic's tales" without wanting to know just how the problem occurs, and how significant it is. Many things that are widely believed are not as simple or true as people think.

The SDS for Rislone does show zinc, sulfur, and phosphorous as elements in the mix.

https://rislone.com/wp-content/uploa.../34405-SDS.pdf

[strokersix]

the "engineering mind" is not typically tuned to accept the "old mechanic's tales" without wanting to know just how the problem occurs, and how significant it is.

This^

When someone says "I was taught" to do it this way that's a great start but it's only good for solving the exact same problem. Even better is understanding how and why because then you can solve new problems, not just the ones you were "taught."

A corollary: "think outside the box" is best done with a thorough understanding of what's in the box first!

[Doozer]

See?!?! It's my engineering mind's fault that everyone thinks I'm a dick.
When I had a mechanic's mind, I had more friends.

--D

[J Tiers]

See?!?! It's my engineering mind's fault that everyone thinks I'm a dick.
When I had a mechanic's mind, I had more friends.

--D

It's a curse. You cannot escape it.

But, if you take up music, or art, as a hobby, you can mitigate it to some extent, at least in the eyes of many.

[CarlByrns]

My experience with EP additives vs brass is based on an set of expensive European transmission synchros that were lubricated (and ruined) with 80/90 EP and a warning from some experienced folks regarding the gearbox on my power hacksaw.

Sometimes caution is the better course of action.