Need help INTERPRETING these test results police cruiser SAE

On 2018-01-11 06:46, Mad Roger wrote:
I agree that there are *many* factors in the act of slowing down a vehicle
with brake friction material heating up causing a loss of the energy of
momentum.

Bollox bollox bollox.

Momentum and energy are quite different quantities, if you want to play
properly at being a scientist.
 
The real question who in the hell fucking cares??



"Mary-Jane Rottencrotch" <usenet@buttocks.local> wrote in message
news:YqCdnX0mlYGk8cfHnZ2dnUU7-eudnZ2d@supernews.com...
: On 2018-01-11 06:46, Mad Roger wrote:
: > I agree that there are *many* factors in the act of slowing down a
vehicle
: > with brake friction material heating up causing a loss of the energy of
: > momentum.
: >
:
: Bollox bollox bollox.
:
: Momentum and energy are quite different quantities, if you want to play
: properly at being a scientist.
 
On 2018-01-11 12:09, Mad Roger wrote:
It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.

Whats the stupid fixation with the coefficient of friction anyway?

As any fule kno, friction is notionally independent of contact area, and
force due to friction is determined by the coefficient of friction *and
the applied force* so if you want more frictional force, you just need
to press the pedal harder, or have more servo assistance.

Simply ignoring all of the other (engineering) considerations which have
been cited, relating to brake performance in the real world, will not
help you be enlightened about anything. It just makes you look like a
dumb fuck trying to be cleverer than your brain permits.
 
On Sat, 13 Jan 2018 08:08:03 -0000 (UTC), Mad Roger
<rogermadd@yahoo.com> wrote:

On Thu, 11 Jan 2018 16:55:12 -0500,
Clare Snyder wrote:

Elementary, my dear Watson. There is a HECK of a lot more to brake
pads than just the coefficient of friction - as Ihave been stating
time and time again.

I found out the DOT Edge Code for the OE Toyota shoes which is
NBK LN508 FF
which is made by "Nisshinbo Automotive Manufacturing, Inc.".

It turns out that you were completely correct where I was hoping this
number would be a "holy grail" where I could use it to better compare two
brake shoes in my hands.

To get a better handle on how to interpret the numbers, I called the main
number at AMECA.ORG in Maryland at 202-898-0145 and spoke to the engineer
in charge of that "AMECA Edge Code Markings" cross reference.

It was a long discussion, the net of which is that this code isn't really
for the consumer.

The engineer said it's kind of like the so-called "serial number" on a
tire, or on a package of baked beans, where if something goes wrong, the
government has a way of tracking down whose fault it is. In addition, he
said that the SAE J866 Chase Test is really a quality metric, and not a
performance metric, even though friction is an outcome of the Chase Test.

The engineer did give me all sorts of personal insight into how to buy
brake pads but overall, he said you can't extrapolate very much real-world
decision-making data from the DOT Edge Code.

Of course, if you miraculously find two pads with the same DOT Edge Code,
then there's a 100% chance that it's the same friction material.

UNLESS it's counterfeit (admitedly likely less than 1% chance -
until it is - - - -
Or, if you find any pads with any of the 19 DOT edge codes that cross
reference to the same AMECA registration number 160426 then they too are
exactly the same friction material.
NAC D9011 FF
NAC LN508 FF
NAC N2009 FF
NBK D9011 FF
NBK LN508 FF <==== this is the OE Toyota brake shoes DOT edge code
NBK N2009 FF
NSA D9011 FF
NSA LN508 FF
NSA N2009 FF
NSC D9011 FF
NSC LN508 FF
NSC N2009 FF
SABC D9011 FF
SABC LN508 FF
SABC N2009 FF
SAC D9011 FF
SAC LN508 FF
SAC N2009 FF
SABC LN508 FF

That's because the AMECA registration number 160426 is for a specific
1-inch square piece of friction material that can be used on any brake pad
or shoe.

But that's really as far as a consumer can go with the edge code, he said.

He knew about all three of the Michigan police studies of EE and FF brake
pads, where those in-depth police cruiser tests also said it's hard to
extrapolate real-world performance from just the EE or FF friction code
they tested.

The AMECA engineer said that there are from 10 to 30 compounds in a brake
friction material, where he opined that Toyota spends enormous energy with
what he called the Tier 1 companies (e.g., Nisshinbo for Toyota) optimizing
the compound for each vehicle; but the engineer said that the aftermarket
suppliers (e.g, Centric, Wagner, Akebono, Axxis, etc.) centralize on about
a half dozen formulas for all their offerings.

In summary, the AMECA Edge Code is only "slightly" useful to a consumer, as
it tells the consumer the most information only if numbers match, but if
they don't match, the only three things it tells the consumer are the
manufacturer, the friction coefficient, and the registration number for the
specific friction material.

BTW, I was tempted to call the Nisshinbo senior principle engineer himself
(Tsuyoshi Kondo, +1-586-997-1000, tkondo@nisshinboauto.com) who submitted
the 1-inch squares for our particular friction material on October 31st
2017 for repeat testing, but I didn't have the nerve to call him for more
information, especially after the AMECO engineer told me this information
is mostly for law enforcement and government use, and not really intended
for consumer use.

The one thing the AMECA engineer told me over and over again though, is
that what we'd want for comparative purposes, has been studied and studied
by the "smartest guys on the planet", and nobody can agree because of
conflicting interest.

So he sympathized with our needs.
 
On Sat, 13 Jan 2018 12:39:51 -0800, Mary-Jane Rottencrotch
<usenet@buttocks.local> wrote:

On 2018-01-11 12:09, Mad Roger wrote:

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.


Whats the stupid fixation with the coefficient of friction anyway?

As any fule kno, friction is notionally independent of contact area, and
force due to friction is determined by the coefficient of friction *and
the applied force* so if you want more frictional force, you just need
to press the pedal harder, or have more servo assistance.

Simply ignoring all of the other (engineering) considerations which have
been cited, relating to brake performance in the real world, will not
help you be enlightened about anything. It just makes you look like a
dumb fuck trying to be cleverer than your brain permits.

I guess we'll have to give the poor guy a break. I suspect he is a
young graduate engineer who has yet to learn how little he knows.
 
On 01/13/2018 12:39 PM, Mary-Jane Rottencrotch wrote:
On 2018-01-11 12:09, Mad Roger wrote:

It seems there *must* be other *major* factors in braking performance,
other than the friction rating of the pads themselves.

That's a hard logical pill to swallow, for me, which is why I asked here,
hoping the s.e.r folks can enlighten us as to why.

Whats the stupid fixation with the coefficient of friction anyway?

As any fule kno, friction is notionally independent of contact area, and
force due to friction is determined by the coefficient of friction *and
the applied force* so if you want more frictional force, you just need
to press the pedal harder, or have more servo assistance.

Yu kleerly paid atenshun to Sigismund the Mad Maths Master! Matron
would be pleesed.

--
Cheers, Bev
"What fresh hell is this?" -- Dorothy Parker
 
On Saturday, 13 January 2018 20:33:13 UTC, BurfordTJustice wrote:
> The real question who in the hell fucking cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.


NT
 
On Thursday, 11 January 2018 23:59:39 UTC, Mad Roger wrote:
On Thu, 11 Jan 2018 09:37:21 -0800 (PST),
pfjw@aol.com wrote:

Differences in brake materials has have limited immediate consequences.
What will change is longevity, pad wear, visual effects, rotor wear,
noise, smell and other irrelevant consequences to the actual need.

With respect to "stopping distance", in the Michigan Police Cruiser study,
they controlled for identical deceleration (thus identical stopping
distance) and measured pedal force.

This is a different test than applying a uniform pedal force and measuring
stopping distance.
https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf

I'm not sure how to extrapolate that information to stopping distances.

I would have thought that as long as the driver & brake servo can apply enough force it would make no difference at all to stopping distances.


NT
 
On Sun, 14 Jan 2018 01:30:23 -0800 (PST),
tabbypurr@gmail.com wrote:

I'm not sure how to extrapolate that information to stopping distances.

I would have thought that as long as the driver & brake servo can
apply enough force it would make no difference at all to stopping
distances.

Thanks for that observation as I'm trying to derive as much real-world
benefit from the police cruiser report as is possible given Clare's astute
observations about EE and FF pads faring differently, but not because of
their coefficient of friction.

There were 3 police tests over the decade, where only the penultimate test
aimed for uniform pedal pressure.
1. https://www.justnet.org/pdf/BRAKEPAD.PDF
2. https://www.justnet.org/pdf/EvaluationBrakePads2000.pdf
3. https://www.justnet.org/pdf/Copy-of-9-22-10-Edited-Brake-Pad-Report-Draft.pdf


The middle test is the one that aimed for a given pedal pressure:
a. 45-to-15mph at 10ft/s/s (approximately ~10 foot pounds +- a few)
b. 70-to-30mph at 22ft/s/s (approximately ~20 foot pounds +- a few)
c. 90-to-0mph at 22ft/s/s (approximately ~30 foot pounds +- a few)

Fundamentally, they said pedal pressure is, effectively, what a human does
all day every day - hence pedal pressure is, arguably, more important in a
well-used "cruising" vehicle that doesn't do panic stops consistently.

A targeted deceleration rate where pedal force is proportional to pad temp.

The other two studies were different.
1. Mostly stopping distance
2. Mostly pedal pressure
3. Mostly driver perception

In the end, the DOT edge code (AMECA edge code) is only slightly useful to
a consumer, I think. I wish it were more useful, but I've gleaned out of it
what I can, and that's the best any of us can hope to do.

I was hoping to get more insight from the scientific and mechanical folks
here.
 
On 1/14/18 10:37 AM, Mad Roger wrote:
I was hoping to get more insight from the scientific and
mechanical folks here.

Ain't gonna happen.
The people what know how this shit works aren't going to
waste their time arguing with your preconceived misconceptions.


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
 
On Sun, 14 Jan 2018 01:27:58 -0800 (PST),
tabbypurr@gmail.com wrote:

The real question who in the hell fucking cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.

It's a valid question of who cares about choosing the proper brake pads.

Bear in mind that the Toyota FF pads are $157 a set at the local
dealership, while at a local parts store, I can get FF pads for $20 a set.

C = Up to 0.15u
E = 0.15u to 0.25u
E = 0.25u to 0.35u
F = 0.35u to 0.45u
G = 0.45u to 0.55u
H = 0.55u to 0.65u
Z = Unclassified

That's a huge difference in price, for material that has the same friction
coefficient, if not quality, don't you think?

So it behooves intelligent people to figure out, scientifically, whether
there is a way to tell what's *different* about those pads.

Everyone understands a number line, but there are non-linear issues here
which nobody here seems (so far) to understand such that they can tell us
how to properly compare the two brake pads based on the information a
consumer would have.

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?
 
Please let this 32nd post be the last one responding to Mr. Neutron and his wildly ignorant stupidities. Pretty please!

Peter Wieck
Melrose Park, PA
 
On Sun, 14 Jan 2018 18:20:33 -0000 (UTC), Mad Roger
<rogermadd@yahoo.com> wrote:

On Sun, 14 Jan 2018 01:27:58 -0800 (PST),
tabbypurr@gmail.com wrote:

The real question who in the hell fucking cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.

It's a valid question of who cares about choosing the proper brake pads.

Bear in mind that the Toyota FF pads are $157 a set at the local
dealership, while at a local parts store, I can get FF pads for $20 a set.

C = Up to 0.15u
E = 0.15u to 0.25u
E = 0.25u to 0.35u
F = 0.35u to 0.45u
G = 0.45u to 0.55u
H = 0.55u to 0.65u
Z = Unclassified

That's a huge difference in price, for material that has the same friction
coefficient, if not quality, don't you think?

So it behooves intelligent people to figure out, scientifically, whether
there is a way to tell what's *different* about those pads.

Everyone understands a number line, but there are non-linear issues here
which nobody here seems (so far) to understand such that they can tell us
how to properly compare the two brake pads based on the information a
consumer would have.

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car). The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it. The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum. It was a real bugger if that happened only on one
front wheel. It would have a MONSTEWROUS pull one time, then brake
fine the next - and you NEVER knew when it was going to pull - or
which way - because sometimes the loose material would grab, sometimes
it would hold properly, andothertimes it would do virtually nothing -
- -

Brake materials are a fine line between a science and a "black art"
 
On Sun, 14 Jan 2018 14:46:53 -0500,
Clare Snyder wrote:

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car).

Hi Clare,
You're actually the *only* one on any of these three newsgroups who knew
the bottom line from the start, which is that we're fucked when we try to
compare a $157 brake pad with a $20 brake pad.

Everyone loves a number line, which is why people buy batteries by warranty
or why they say the stupid line that "you get what you pay for" when we all
know that a $300 set of speakers at Toyota gets you a crappy speaker
compared to a $50 set at Crutchfields.

So you can never tell by price. You can only tell by quality.
And there's no way to *compare* quality, it seems.

You knew that. Which is why you stick to name brands. Which is fine, as
name brands is just another way of saying you buy by a number line, where
the number line only has parts on the right and left of zero.

Brands to the right of zero you'd buy (e.g., Napa or Wagner) and brands to
the left you wouldn't buy.

But that sucks too as a determinant although at least with the DOT Edge
Code, we can tell, for sure, which company made the friction material (so
we could tell that an Axxis pad is the same as a PBR which is the same as a
Metal Masters pad, for example).

The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Yes. That's what the AMECA engineer basically said. He even said, many
times, that the brake engineer might not even know himself, unless he
himself submitted the pad material for testing.

So, basically EVERYONE is buying brake pads completely blind.

If that's not sad to you, it is to me.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it.

If you have the DOT Edge Code, we could tell at least who made each
friction material, and whether they're on other pads, and whether they
truly were the same or not, and what the friction coefficients were.

But that's about it for what we could tell about the two pads from just
having them both in our hands.

That's sad.

The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

I don't even look at the marketing bullshit because one spec of dust and
they can call it ceramic. There's no law or rules. They can put a spec of
iron and then call it semi metallic.

The only laws are they can't put asbestos in it.

The rest is marketing bullshit. We've been there, so let's not go there
again. :)

We're essentially choosing brake pads almost completely blind.
And that's sad.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum.

Yes. I'm not covering defects in workmanship or design of the backing.
I'm just covering the friction material here, because friction is the
fundamental thing a brake pad does.

I know all about the issues that we will never be able to compare pads with
such as longevity of the pads and rotors, fitment, noise, dusting, etc.

> Brake materials are a fine line between a science and a "black art"

I agree that for the *formulator*, it's likely halfway between science and
a black art, but for the poor consumer, it's complete marketing bullshit.

Nobody, it appears, actually knows anything about buying brake pads when
they have two pads they've never seen before in their hands.

You have the EXPERIENCE to pick a pad, but even if I shoved two pads that
you have never seen before (such as two I'm going to need to compare), you
can't compare them either (unless you know the brand).

Even then, you harp on the conterfeits, so unless you know a telltale sign,
you can't tell from the brand either, especially when buying online.

SO it's just sad, sad, sad, that we're all utterly blind when it comes to
comparing brake pads. I think that's very depressing. We're at the mercy of
marketing bullshitters and idiots who do brake pad reviews on amazon that
make no sense and aren't for the same car and compare things like worn old
pads against brand new pads, and the butt dyno takes over from there.

All those reviews are basically worthless.
All the marketing bullshit is basically worthless.

The one dream I had was that this AMECA Edge Code could tell me a lot, and
it does tell me three things, but that's it.

Sigh. It's just sad.

I do thank you for your help, as you're the only one, I think, who knew
what he was talking about from the start. I had to learn it. You already
knew it.
 
On 1/14/2018 5:11 PM, Mad Roger wrote:
On Sun, 14 Jan 2018 14:46:53 -0500,
Clare Snyder wrote:

In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

That's kind of a sad revelation for this newsgroup, don't you think?

Not at all. Even a "brake engineer" would not be able to tell ypou
how to tell the good fromthe bad (or less good - don't knowthere is
any "bad"brakes on the market - even a lot of the "counterfeit" stuff
will stop the car).

Hi Clare,
You're actually the *only* one on any of these three newsgroups who knew
the bottom line from the start, which is that we're fucked when we try to
compare a $157 brake pad with a $20 brake pad.

Everyone loves a number line, which is why people buy batteries by warranty
or why they say the stupid line that "you get what you pay for" when we all
know that a $300 set of speakers at Toyota gets you a crappy speaker
compared to a $50 set at Crutchfields.

So you can never tell by price. You can only tell by quality.
And there's no way to *compare* quality, it seems.

You knew that. Which is why you stick to name brands. Which is fine, as
name brands is just another way of saying you buy by a number line, where
the number line only has parts on the right and left of zero.

Brands to the right of zero you'd buy (e.g., Napa or Wagner) and brands to
the left you wouldn't buy.

But that sucks too as a determinant although at least with the DOT Edge
Code, we can tell, for sure, which company made the friction material (so
we could tell that an Axxis pad is the same as a PBR which is the same as a
Metal Masters pad, for example).

The "brake engineer" would likely beable to tell
you which of "his" product is better - but not necessarily if his was
betteror worse than another brand.

Yes. That's what the AMECA engineer basically said. He even said, many
times, that the brake engineer might not even know himself, unless he
himself submitted the pad material for testing.

So, basically EVERYONE is buying brake pads completely blind.

If that's not sad to you, it is to me.

Back when I was a Toyota tech and service manager there were at least
2 different formulationsof brake pad that fit numerous Toyota vehicles
of the time - one was used up to a particular production date, and
another after. Both were available as replacement parts, and I always
used the one, regardless of vehicle production date, because it
stopped better and I could install the second and third set without
having to replace rotors. It was a difference between the metal used
in the "semi metallic" lining. One was magnetic - the other had brass
in it.

If you have the DOT Edge Code, we could tell at least who made each
friction material, and whether they're on other pads, and whether they
truly were the same or not, and what the friction coefficients were.

But that's about it for what we could tell about the two pads from just
having them both in our hands.

That's sad.

The brass stopped better and didn't cause pitting of the
rotors. The pads didn't last as long, but virtually nobody ever
actually wore out the "magnetic" ones before the rotors needed
replacing, so the pad life, in and of itself, was a total non-issue.
IIRC the brass was the early pad and the iron was the
replacement/update.

I don't even look at the marketing bullshit because one spec of dust and
they can call it ceramic. There's no law or rules. They can put a spec of
iron and then call it semi metallic.

The only laws are they can't put asbestos in it.

The rest is marketing bullshit. We've been there, so let's not go there
again. :)

We're essentially choosing brake pads almost completely blind.
And that's sad.

The same situation rose years back on, I believe, FORD brake shoes
where the linings would deteriorate and fall apart before the half
wear point. They went from rivetted to bonded, and then the glue
started letting go, and the entire lining would free-wheel between the
shoes and the drum.

Yes. I'm not covering defects in workmanship or design of the backing.
I'm just covering the friction material here, because friction is the
fundamental thing a brake pad does.

I know all about the issues that we will never be able to compare pads with
such as longevity of the pads and rotors, fitment, noise, dusting, etc.

Brake materials are a fine line between a science and a "black art"

I agree that for the *formulator*, it's likely halfway between science and
a black art, but for the poor consumer, it's complete marketing bullshit.

Nobody, it appears, actually knows anything about buying brake pads when
they have two pads they've never seen before in their hands.

You have the EXPERIENCE to pick a pad, but even if I shoved two pads that
you have never seen before (such as two I'm going to need to compare), you
can't compare them either (unless you know the brand).

Even then, you harp on the conterfeits, so unless you know a telltale sign,
you can't tell from the brand either, especially when buying online.

SO it's just sad, sad, sad, that we're all utterly blind when it comes to
comparing brake pads. I think that's very depressing. We're at the mercy of
marketing bullshitters and idiots who do brake pad reviews on amazon that
make no sense and aren't for the same car and compare things like worn old
pads against brand new pads, and the butt dyno takes over from there.

All those reviews are basically worthless.
All the marketing bullshit is basically worthless.

The one dream I had was that this AMECA Edge Code could tell me a lot, and
it does tell me three things, but that's it.

Sigh. It's just sad.

I do thank you for your help, as you're the only one, I think, who knew
what he was talking about from the start. I had to learn it. You already
knew it.

And all that is different from buying a bag of white flour
to make cookies in what way exactly?

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
 
On Sunday, 14 January 2018 16:37:09 UTC, Mad Roger wrote:
On Sun, 14 Jan 2018 01:30:23 -0800 (PST),
tabbypurr wrote:

I'm not sure how to extrapolate that information to stopping distances..

I would have thought that as long as the driver & brake servo can
apply enough force it would make no difference at all to stopping
distances.

Thanks for that observation as I'm trying to derive as much real-world
benefit from the police cruiser report as is possible given Clare's astute
observations about EE and FF pads faring differently, but not because of
their coefficient of friction.

There are presumably 2nd order differences in pad performance, but we've no idea what they are. EE versus FF is not it seems the relevant criterion as long as the car can apply enough force to lock wheels with the pads. Whether all modern cars can do that with EE or not I also have no idea. FWIW certainly all historic ones can't.


I was hoping to get more insight from the scientific and mechanical folks
here.

you're getting a bit, but afaik none of us are brake specialists or researchers.


NT
 
On Sunday, 14 January 2018 18:20:35 UTC, Mad Roger wrote:
On Sun, 14 Jan 2018 01:27:58 -0800 (PST),
tabbypurr wrote:

The real question who in the hell fucking cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.

It's a valid question of who cares about choosing the proper brake pads.

Bear in mind that the Toyota FF pads are $157 a set at the local
dealership, while at a local parts store, I can get FF pads for $20 a set..

C = Up to 0.15u
E = 0.15u to 0.25u
E = 0.25u to 0.35u
F = 0.35u to 0.45u
G = 0.45u to 0.55u
H = 0.55u to 0.65u
Z = Unclassified

That's a huge difference in price, for material that has the same friction
coefficient, if not quality, don't you think?

That's retail. And really the difference is greater, I once bought a set of 4 brake shoes for ÂŁ1, that's under $2. They performed without any issue. Why? No-one here wants to buy brake parts from scrapyards, even though they're the same parts you get in the shops.


In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

if both do the job ok, $20 is the intelligent buying decision.


> That's kind of a sad revelation for this newsgroup, don't you think?

No, it's an electronics newsgroup.


Moving to historic vehicles, how would I find out which friction rating oak is?


NT
 
On Sunday, 14 January 2018 18:20:35 UTC, Mad Roger wrote:
On Sun, 14 Jan 2018 01:27:58 -0800 (PST),
tabbypurr wrote:

The real question who in the hell fucking cares??

I didn't, until I found the brake pads fitted by a quick nationwide chain a year earlier were totally disintegrating.

Funny thing is you can get the same brake pads at a scrapyard for a fraction the price, but no-one wants to.

It's a valid question of who cares about choosing the proper brake pads.

Bear in mind that the Toyota FF pads are $157 a set at the local
dealership, while at a local parts store, I can get FF pads for $20 a set..

C = Up to 0.15u
E = 0.15u to 0.25u
E = 0.25u to 0.35u
F = 0.35u to 0.45u
G = 0.45u to 0.55u
H = 0.55u to 0.65u
Z = Unclassified

That's a huge difference in price, for material that has the same friction
coefficient, if not quality, don't you think?

That's retail. And really the difference is greater, I once bought a set of 4 brake shoes for ÂŁ1, that's under $2. They performed without any issue. Why? No-one here wants to buy brake parts from scrapyards, even though they're the same parts you get in the shops.


In the end, I don't see any indication whatsoever that anyone here knows
how to properly compare the performance of those $157 and $20 brake pads
and shoes in order to make an intelligent buying decision.

if both do the job ok, $20 is the intelligent buying decision.


> That's kind of a sad revelation for this newsgroup, don't you think?

No, it's an electronics newsgroup.


Moving to historic vehicles, how would I find out which friction rating oak is?


NT
 
On Sunday, 14 January 2018 23:11:20 UTC, Mad Roger wrote:
On Sun, 14 Jan 2018 14:46:53 -0500,
Clare Snyder wrote:
8

I agree that for the *formulator*, it's likely halfway between science and
a black art, but for the poor consumer, it's complete marketing bullshit.

Nobody, it appears, actually knows anything about buying brake pads when
they have two pads they've never seen before in their hands.

You have the EXPERIENCE to pick a pad, but even if I shoved two pads that
you have never seen before (such as two I'm going to need to compare), you
can't compare them either (unless you know the brand).

Even then, you harp on the conterfeits, so unless you know a telltale sign,
you can't tell from the brand either, especially when buying online.

SO it's just sad, sad, sad, that we're all utterly blind when it comes to
comparing brake pads. I think that's very depressing. We're at the mercy of
marketing bullshitters and idiots who do brake pad reviews on amazon that
make no sense and aren't for the same car and compare things like worn old
pads against brand new pads, and the butt dyno takes over from there.

All those reviews are basically worthless.
All the marketing bullshit is basically worthless.

The one dream I had was that this AMECA Edge Code could tell me a lot, and
it does tell me three things, but that's it.

Sigh. It's just sad.

if they all work ok it's not sad, it's a nonissue
 
There's something happening here
But what it is ain't exactly clear
There's a man with a gun over there
Telling me I got to beware

I think it's time we stop
Children, what's that sound?
Everybody look - what's going down?

There's battle lines being drawn
Nobody's right if everybody's wrong
Young people speaking their minds
Getting so much resistance from behind

It's time we stop
Hey, what's that sound?
Everybody look - what's going down?

What a field day for the heat
A thousand people in the street
Singing songs and carrying signs
Mostly saying, "hooray for our side"

It's time we stop
Hey, what's that sound?
Everybody look - what's going down?

Paranoia strikes deep
Into your life it will creep
It starts when you're always afraid
Step out of line, the men come and take you away

We better stop
Hey, what's that sound?
Everybody look - what's going down?

We better stop
Hey, what's that sound?
Everybody look - what's going down?

We better stop
Now, what's that sound?
Everybody look - what's going down?

We better stop
Children, what's that sound?
Everybody look - what's going down?

Stephen Stills


Guys and gals:

a) There are many thousands of mechanics out there who _REALLY DO_ have the best interests of their customers at heart.
b) Many of them are perfectly willing to share their experiences with their customers.
c) And, for the most part, they are willing to share sources and reasons for them.
d) OEM parts, for the most part (pun intended) will do the job nicely. I just replaced the rear brakes on my 2014 Ford C-Max Energi at 67,000 miles - the front brakes are still at 70%. I used 100% OEM parts, at a material cost of $180, retail-from-Ford. NOTE: As this is a plug-in hybrid, dynamic braking, if exploited properly, does most of the actual work involved. Saving the brakes.

Deep analysis is not required. Attention to life-safety *IS* required. And that is ALL that is required.

Understanding brakes 101:

The primary job of brakes is stopping the vehicle in a controlled, safe, reliable fashion.
Whatever wearing parts as are necessary to complete this task are sacrificial to the primary job.
Manufacturers have absolutely no interest whatsoever in compromising this system at any level and in any way. Too many Lawyers out there for them to take such an absurd risk.


Kinda-sorta makes debates on the number of angels residing on the head of any given pin, whether dancing, or not, patently absurd. FULL STOP.

Peter Wieck
Melrose Park, PA
 

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