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Mad Roger Mad Roger is offline
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Default Need help INTERPRETING these test results police cruiser SAE J866a Chase Test

On Mon, 15 Jan 2018 12:23:01 -0500,
Clare Snyder wrote:

Pad vibration - which has an effect on gas venting, counterd by the
effect of reduced pad contact


That makes sense that the outgassing of pad A can be vastly different than
that of pad B, and, in fact, they "burnished" the pads in the police test
to minimize the initial presumed-far-greater effect of that as the
adhesives heated up for the first time and vented gases.

May not be a HUGE difference, but it is possibly a factor.


Occam's Razor logic tells us that only one of 2 things is happening:
a. There is a huge as-yet-unnamed second-order effect, or,
b. There is a combination that results in a huge second-order effect.

That there is a huge second-order effect (after friction), there can be no
logical doubt.

But what is the 2nd-order effect's cause and can we test for it?

Also heat
CONDUCTANCE - metallic pads conduct more heat to the caliper than
ceramice - making the boiling point of the fluid more critical (if
running metallic or semi-metalic pads you want to be sure to be
running DOT4, not DOT3, and you want it freash and dry).


Two Occam's Razor points on that observation above, which is correct.

1. While this vehicle specs DOT3, I'll put in DOT4 instead.
2. Metal versus semi-metallic versus ceramic is marketing bull****

I know there are no laws that differentiate between metal, ceramic, and
semi-metallic - as I've personally spoken to the people who make the
Axxis/PBR/Metalmasters pads. They told me it's all bull**** only they said
it far more politely and less succinctly than I just did.

Suffice to repeat that a spec of dust makes a pad ceramic, just as a spec
of iron makes it semi-metallic.

I posit marketing came up with these wonderful good/better/best number-line
decisions for people since people (like Terry Schartz seems to be) want a
simple number line instead of those oh-so-very-complex quality
specifications.

Where's Jeff Liebermann when you need him!!!!!!!!!!!!!!!!!!!!