Valve oil

[David Holloway <musichem@cts.com>]

VALVE OILS vs PERFORMANCE
 
INTRODUCTION:
 
Our company was founded by a musician and a chemist, hence the name
MusiChem, Inc. The information we offer is from our in-house
laboratories and field tests, and is the result of a company we
started in 1972. However, please understand that although we
manufacture valve oil, this is not an advertisement to buy our
products; the information is applicable to any piston valve oil.
 
The most common question is "Are all valve oils the same ?" Store
owners that do not play trumpet will tell you that all valve oils
are basically the same. However, the differences between valve oils
are serious, verifiable, and have a dramatic effect on how your horn
will perform. Valve oils for trumpets fall into 3 groups: Type 1 are
the low technology formulations based on a modern day version of
kerosene (the odor is quite obvious); Type 2 are high viscosity oils;
and Type 3 are light weight oils with little or no petroleum odor.
By the way, the word "premium" is not a technical term.
 
There are so many trumpet oils available because there are so many
businessmen who combine a little kitchen chemistry with a lot of
advertising dollars to create a product. However, developing a
functionally correct lubricant requires a thorough understanding of
Material Science and Fluid Dynamics. Ignoring these principles has
resulted in the proliferation of fundamentally poor valve oils.  For
example, one trumpet oil company that uses silicone oils is ignoring
the hysterisis and buildup problems that plague silicones when used
on sliding metal surfaces. In fact, a primary manufacturer of
silicone - Dow Corning- specifically recommends against using
silicone for sliding metal/metal lubrication.
 
"Some oils gunk up valves."   We have all heard this misleading
statement, but when we complete this presentation, you will have
enough understanding to never again suffer from a "gunked up valve".
The statement, however, leads us into the main part of the subject:
 
Speed and Endurance.
 
The primary purpose of valve oil is to provide a thin film of
slippery fluid which clings to the valve and casing, thereby acting
as a barrier to prevent direct metal to metal contact between these
critical surfaces. A thick oil (Type 2) may be slippery and provide
an excellent barrier, but it would cause the valves to be very slow.
A thinner fluid (such as kerosene in Type 1 ) would be fast initially
but its rapid evaporation would cause the valves to slow down
quickly, and eventually stop moving altogether. Consequently, long
ago we recognized that there are two major performance
considerations in researching a new oil for piston valves: Speed and
Endurance. To ignore either in favor of economy or naivet, is to
guarantee disappointment for the musician.
 
 
SPEED
 
The most important quality in a valve oil is its ability to promote
speed by reducing friction. But, the oil also causes some resistance
of its own. This measured resistance is called viscosity, and the
unit of measurement is centi-Stokes (cSt.).  Musicians seeking a
"thin" oil are simply looking for a low viscosity oil. Although you
can get a rough idea about how viscous an oil is by applying some to
an inclined surface and watching it run, the accurate way to measure
viscosity is with capillary viscometers. Since actual viscosities of
different oils have not heretofore been published, we have presented
some in table below. These oils were purchased from different
stores.
 
    Products               Viscosity (cSt)
 
    WATER                  1.00
    MINERAL SPIRITS        1.34
    CLARK TERRY            1.83
    BENGE                  1.99
    BLUE JUICE             1.99
    PLAYERS                2.15
    JUPITER                2.20
    ROCHE-THOMAS           2.31
    HOLTON                 2.38
    HYBRID 141-A7          3.02
    PRO-OIL RED            3.61
    SPACE FILLER II        3.72
    AL CASS                3.73
    PRO-OIL BLUE           3.80
    SPACE FILLER I         5.10
    SLIDE (for trombones)  5.12
    ALISYN                 7.59
 
 
As you can see, several valve oils are so "thin" that they approach
the viscosity of water, while others are very viscous.Water has by
far the lowest viscosity, but if low viscosity was the only criterion
for speed, then the spit in your horn would be enough to keep your
valves fast. The fingers of an experienced trumpet player can sense
even the slightest valve hesitation, and this experience has shown
that the optimum viscosity for speed lies somewhere in the 1.1 - 5.0
cSt range. In developing HYBRID (our experimental reference standard
for piston valves) we have discovered that the optimum viscosity for
valves in good condition is in the 2.5 - 4.0 cSt. range. However,
badly worn valves can tolerate or even benefit from somewhat higher
viscosity oils. Nonetheless, viscosity isn't the entire answer;
speed means nothing if the action is not smooth, or if the valves
become slow in the middle of a performance. A working musician
cannot afford to even think about his valves during a performance.
In other words, what about endurance ?
 
In future correspondence we will discuss endurance, corrosion, the
best technique for cleaning a trumpet, and why horns gunk up.  We
will stop here and await any questions from the list.
 
David Holloway
MusiChem, Inc.
1-800-PRO-OILS