<VV> STP and the Scerwdriver

[Smitty]

Smitty Says;  I am not an oil engineer and because of the years since I was 
in the school I am not even sure of the terminology.  Nor am I sure of the 
application.  But here goes.  When I worked for Philips 66 we who were even 
remotely involved in sales had to go to schools on the properties of oils so 
we could sound half smart when talking to customers.  There is a thing 
called dynamic barrier when oil is pumped between flat bearings and 
crankshafts.  It keeps the metals separated when pressure is applied to 
press them together.  If oil too light in viscosity is used the oil will 
extrude out from between the metals and galling will occur.  If oil too 
heavy in viscosity is used the dynamic barrier will rip or pull apart and 
again you will have metal to metal contact.  There is actually a big wide 
range of viscosity that can be satisfactory but naturally the engineers will 
specify a median viscosity to provide protection under high and low heat 
operating conditions.
STP is a viscosity improver and in it's unmixed state is very thick and 
slick feeling.  Slick, not necessarily because it is such a superior oil , 
but because at low speeds of relative motion its thickness of barrier 
provides contact prevention between two components.  It might make a heck of 
a lubricant in a differential but in an engine at 7,000 rpm bearing life 
would be very marginal.  The point being that there is a lubricant for every 
application and there is often a fine line between what you can and can not 
get away with.
Which brings us back to screwdrivers.  When you wet a screwdriver bit with 
STP and then try to hold on to it, chances are you will use the same fingers 
you tried with the conventional oil.  Chances are you will be holding on 
(pinching) just about the same tightness.  The regular oil with a viscosity 
of probably 10 to 40 extruded out from under your fingers and allowed skin 
and fingerprint contact with the screwdriver.  What's the viscosity of STP? 
100- 120-150?  I don't know but it is going to take a lot longer to squeeze 
it out for the same skin and fingerprint contact you had with the oil. 
Chances are your fingers will get tired and your grip will weaken before 
that happens.  In any event, the holding up a screwdriver with STP in your 
fingers proves absolutely nothing.
So maybe I am all wet about all this.  I just hate snake oil salesmen