Need help INTERPRETING these test results police cruiser SAE J866a Chase Test

On 16/01/2018 1:48 PM, Fox's Mercantile wrote:
> On 1/15/18 8:28 PM, Mad Roger wrote:
>> Â* [ Lot's of stupid repetitive **** deleted ]
>
> On the rare occasions I do my own brakes, I use either NAPA,
> Warner or OEM parts. Not whatever is cheapest at Auto Zone,
> JC Whitney or Pep Boys.
>
> The rest of the time I just take the vehicle to a reputable
> mechanic and tell him what I want. It gets done right.
>
> All your blathering is like arguing with your doctor, "But I
> read on Facebook (or WebMD)."
>
>
May the Lord save us from those who *think* they know!

--

Xeno

On 16/01/2018 1:58 PM, Clare Snyder wrote:
> On Tue, 16 Jan 2018 02:10:29 -0000 (UTC), Mad Roger
> > wrote:
>
>> On Mon, 15 Jan 2018 07:54:12 -0800 (PST),
>> Terry Schwartz wrote:
>>
>>> Yes we know, it's soooooooo sad......
>>
>> I get your point, even ensconced inside the sarcasm, so I'll just say it
>> bluntly that I do realize 99.99% of the people out there do not care that
>> they're completely unable to intelligently purchase things using a modicum
>> of logic.
>>
>> These people all want a "number line" decision, where they can use the
>> good, better, best by "marketing derived" criteria, such as silly words
>> like "ceramic" (where one spec of clay makes it a ceramic) and
>> "semi-metallic" (where one spec of iron makes it metallic).
>>
>> You're one of those people, most likely (based on Occam's Razor deduction),
>> and that's fine.
>>
>> You *think* you're intelligently choosing a brake pad, and that's fine too.
>
> And YOU think YOU are smart. (nobody else does - sorry to break your
> bubble)

I caught on to that very early in the piece. That's why I deduced that
discussion with mad roger was not a fruitful use of my time.

As you have discovered.
>>
>> You may even buy by one of the three marketing-induced criteria:
>> a. If you're cost conscious, you buy the cheapest FF that fits.
>> b. If you're value conscious, you buy the mid FFs (with a small price bump)
>> c. If you're status conscious, you buy the high FFs (bigger price jump)
>>
>
> and if you are SMART you buy the type of pad that matches
> yourdriving requirements - which for most commuters is a standard
> organic pad, for heavy duty use, a semi metallioc, and for high speed
> light duty, generally a ceramic.
>> I'm not like you.
>> I like to *understand* that which I buy.
>
> And yet you most certainly do NOT when it comes to brakes. You are
> totally clueless and uneducatable

Amen to that! Just wants to argue the toss, that is all.
>>
>> That's my take on the main difference between you and me base on the one
>> line you wrote.
>>
>> I like to make intelligent buying decisions.
>> You apparently don't care to - and that's fine.
> and you seem to be totally incapable of it.
>
He is.

--

Xeno

On Tue, 16 Jan 2018 02:28:52 -0000 (UTC), Mad Roger
> wrote:

> On Mon, 15 Jan 2018 14:27:23 -0500,
> Clare Snyder wrote:
>
>> Metallic pads are more aggressive than ceramics and organics (and they
>> are harsher on rotors and noisier)
>> Ceramics last longer and dust less - and stop better than organics,
>> but are not as effective when cold as metallics.
>> Ceramics can have small amounts of iron, steel, copper, or brass in
>> them -as can "organics The tree-huggers in Cali are trying to outlaw
>> copper bwcause it kills alge etc in runoff water fromthe roads -
>> leaving us with the more agressive ferrous materials.
>
>Except that Axxis marketing told me, personally, that all these words are
>marketing bull**** (he used nicer terms than that).




from the PBR brake site :

PBR Axxis Metal Master Brake Pads, Ultimate Brake Pads, and Deluxe
Brake Pads

Note: The FMP Group Australia Pty. Ltd., is the manufacturer of Axxis
and PBR brand brake pads; these pads are identical.

Axxis Ultimate Brake Pads

Ultimate

The PBR Axxis Ultimate brake pads feature a special Kevlar® and
ceramic-strengthened formula with a high co-efficient of friction and
excellent high temperature wear and fade resistance. Designed for
ultra-high performance driving and hard-braking applications, PBR
Axxis Ultimate pad users will benefit with extreme stopping power and
high resistance to brake fade at high temperatures, meaning the
decrease in friction over repeated heavy duty stops, as the
temperature increases, is minimal. PBR Axxis Ultimate pads boast a
maximum continuous working temperature of 550° C (1022° F degrees).
Consistent throughout its operating temperature range, you’ll get
dependable, predictable stops time after time while maintaining a
solid pedal feel.



Axxis Metal Master

Metal Master


Metal Master: Non-asbestos, semi-metallic compound provides the
highest fade resistance among leading semi-met brake pads. They
deliver proven longer pad and rotor life, with low rotor scoring and
quiet braking.
•Designed for applications requiring the highest performance
•Premium quality, non-asbestos, semi-metallic formula
•Unique formula offers reduced brake dust, fade and squeal
•Provides the ultimate stopping power under all conditions
•Virtually eliminates squeal and dust
•Improved cold effectiveness
•Improved pad life

Axxis Deluxe

Deluxe

Exclusive OE equivalent organic compound provides outstanding stopping
power with very low fade. Extremely quiet with proven long pad and
rotor life and low rotor scoring. Provides measurably longer life and
has extreme resistance to heat while delivering consistent, smooth
braking performance.
•Formulated from the latest premium quality, organic materials
•Low dust, low squeal
•Delivers quality braking performance
•Rotor friendly
•Smooth stopping power
•Low dust and squeal
•Extended pad life

Get yourself a set of PBR Axxis Ultimate, Metal Master, or Deluxe pads
today! Brake pads! High Performance Brake Pads! Theres nothing
better for braking performance than a good brake pad.



So PBR makes 3 differentlines of brakes. One is sold as AXXIS
Ultimate, oneas Axxis Metal Master, and one as Axxis Deluxe. (Also
sold underthe PBR brand)

3 totally different pads for diufferent use - all spelled out on the
PBR brake products web site. If you spoke to a PBR marketing person
you spoke to an idiot who doesn't know their product line, and knows
even less about brakes. What you got from HIM WAS marketing bull****.


>
>Do you think I don't call these people up when I have their numbers?

Whoever you called gave you VERY bad information.
>
>> You can tell if a ceramic or semi-metallic pad is using ferrous
>> materials with a magnet.
>
>Hmmmmhmmmhmmm... this is interesting. I like it! If the test works, that's
>a nice test. I'm gonna have to bring a magnet with me to the web when I
>look them up online!

And you are still stupid enough to think you have to buy online -- I
just cannot figure you idiots out.
>
>Seriously though, it's nice if the pad is in your hands. I'll bring a
>magnet with me if I end up buying them from the parts store. And I can test
>the old shoes and pads when I take them off.

But metallics are not NECESSARILLY magnetic - because they can be
copper or brass - and even ceramics can have some metal in them - as
can some organics. You just DON"T GET IT.
>
>Good idea if it works.
>Can others concur it works?
>
>> The MAJOR companies - I'm not talking your second and third tier
>> "boutique" rmarketers likw those favourite brands of yours - do
>> SIGNIFICANT reasearch and engineering, often develloping specific
>> friction materials (and combinations) for different vehicles. The
>> Wagner thermoquiet formulation on your Ford may be significantly
>> different than on your Dodge or GM, or Toyota.
>
>The Ameca engineer talked about 1st tier but he wouldn't tell me which
>companies that is, so I don't know what you know.

Get used to it.
>
>He did say that aftermarket makes only a handful of formulations that they
>fit to all cars.

Which is pure bull;**** when talking about tiuer one aftermarket
suppliers (which are also OEM suppliers in most cases)
>
>> You decide which characteristics are impoetant to you - extreme high
>> speed performance at the expense of life and quiet and dusting, or
>> silence, long rotor life, and low cost at the expense of high speed
>> performance and pad life, or good all-round performance, pad life, and
>> rotor life at a significantly higher cost to decide if you want
>> semi-metallic, organic, or ceramic pads, then you go to a trusted
>> reseller of a major brand - wagner, TRW, Akebono, Brakebond, Mintex
>> rtc and buy their premium (highest quality) set of whichever
>> technology meets your desires.
>
>That's like saying you decide the characteristics of a wife, and then go
>and marry her. It's not extrapolatable with the information you have.
>
>It's just not.
>
>And you seem to buy on a number line, like most people, and that's fine,
>for you. I like to buy by specs, and they just don't exist.
>
I do NOT buy on a "number line" - I buy by spec. I buy organic, semi
metallic, or ceramic depending on what brake characteristics I need
and what I'm willing to pay.


>SO I'm ****ed.

You've done it to yourself.
>
>> I say the "premium" set meaning the one that comes with all the
>> required clips, shims, pins, etc to do a proper install without having
>> to source other parts elsewhere or re-use sub-optimal used parts.
>
>Of course. That's a given that the hardware needed is there, and that it
>fits. In the case of the Toyota drums, the only hardware needed for sure is
>the U clip which has to be bent. The OE pads come also with circular
>retainers.

You keep going between pads and shoes. There is so much difference -
hardly oranges to oranges - barely apples to oranges - more like
rutabagas to apples.
>
>> Engineering isn't bull****. As an "engineer" you should appreciate
>> that anless you got your degree in a box of crackerjacks.
>
>You missed what I said, or I didn't say it right.
>Specifications are not bull****.
>Marketing spin is bull****.

ANd I don't look at "marketing spin" I look at "real" specifications.
What KIND of brake material is it? Knowing the KIND of material I can
pretty accurately deduce the basic qualities of the brake product -
and knowing the manufacturer AND the composition, I can make a pretty
good deduction as to quality and suitability for my purpose. Without
any "number line" or "friction rating"
>> The SCIENCE is there. (mixed with a bit of black magic - as all
>> "science" is).
>
>The science is only in the hands of the formulators.
>Nobody else has access to that science.
>
>> When you buy from Rock Auto, you are USUALLY buying prime product that
>> came off someone's shelf when they went out of business, or warehouse
>> overstock, or "open box" product, or product with damaged packaging
>> due to fading from being on a shelf too long, moisture damage, smoke
>> damage, etc. When you buy "brand name" from them, you are generally
>> getting top quality genuine pruduct at pennies on the dollar.
>
>This is good to know because Rock Auto has really low prices!
>They were so low, they scared me. That's how low they were.
>
>> No, in your case it is shear paranoia, over a base layer of
>> ignorance.
>
>I don't have any paranoia. You *think* I do, and that's fine.
>But I don't.
>I just don't trust marketing as much as you seem to trust them.

And where do you get the idea I trust "marketing"?????
>
>> WHo do you think engineers and manufactures the OEM brake material for
>> Ford, GM, Toyota,Chrysler, etc?
>
>That's a good question. The AMECA engineer said only the OEMs spend the
>immense time to get the formulation right. So that would say that, if you
>like what the OEMs did for you, that you should pay the $157 for OEM FF
>shoes and not the $20 for aftermarket FF shoes.

No, for the Toyota you buy Akebono brake shoes - the aftermarket
supplier that also produces the OEM brakes for a large percentage of
Toyota vehicles (Toyota generally "dual sources" all major parts that
the source from outside, like brakes, shoicks, lenses, bulbs, and
spark plugs. If one supplier has a problem they cut them off until the
problem is solved. (for spark plugs it was always either Nipon Denso
or NGK,, foir many parts like AC it was Aisin or Denso.

The MAJOR Tier one aftermarket suppliers are also major OEM
suppliers.

TRW, Walker,Monroe, Delphi, and a host of other manufacturers design
and build all kinds of parts for the OEM market - as well as the
aftermarket.
>
>> They do NOT design and manufacture the stuff themselves. They have
>> that done by the likes of Wagner, TRW, Akebone, American Brakebond,
>> etc. These are the major suppliers to BOTH the OEM and the aftermarket
>> and OEM REplacement .
>
>In the case of Toyota, it's Nisshinbo Automotive Manufacturing, Inc.

That will be ONE of their brake suppliers.
>
>But you bring up a good point, which is what the AMECA engineer said, which
>is to buy "regionally" if you don't go OEM.
>
>His algorithm was to buy a brand from the same region as where your OE
>shoes were made. If OE is from Germany, then buy a German-built pad. If OE
>is Japanese, then buy a Japanese pad.
>
>He didn't explain in detail why, but his point may be the same as yours,
>which is that there aren't a whole lotta' manufacturers out there, but
>luckily, with the AMECA Edge Code, we know the manufacturer of *every*
>brake pad out there, and the code for the specific material.
>
>> Don't be such a stiubborn paranoid "engineer". YOU will NEVER
>> understand EVERYTHING about your OWN field of expertise, muchless a
>> field totally outside your reralm.
>
>I *hate* not being able to make an intelligent choice based on
>specifications. I just hate it.
>
>And, you just can't make an intelligent choice based on specifications for
>brake pads because all you really know are who made it, what it's friction
>is, and whether the compound is exactly the same as another.
>
>That's not enough to make an intelligent comparison.
>And you never will have the capability to test them scientifically.
>
>So we're all blind - although most people don't seem to realize they're
>blind.
>
>> When I buy Wagner or Akebono aftermarket OEM Replacement parts, etc
>> from a supplier like NAPA i KNOW what I am getting.
>
>I've had Jurid, Textar, Akebono, and PBR on my car.
>They're all the same to me.

Then what are yopu fussing about????????

>The first week they feel vastly differently, then the same forever more.
>
>The first week, we're comparing old pads to new pads, mind you.
>
>> And if you are any kind of an engineer you KNOW that you have
>> oversimplified that last statement
>> A 10 lb beach ball and a 10lb bowling ball WILL fall at a different
>> speed in free air. Youdidn't take into account the difference in wind
>> resistance due to size.
>
>Yes. I know. Everyone knows that. Even non engineers.
>But my point is that it wasn't obvious until Gallileo tested it.
>So millions of people thought otherwise, because intuitively it seems that
>it woudl be the case.
>
>You knew that. A feather and a bowling ball will fall differently, in air,
>but the same in a vacuum. We all know that.
>
>My only point there was that intuition is almost always wrong.
>Anyone who trust their intuition, is almost always wrong.

Not if their "intuition" is "educated"
>
>Don't even get me started on high-octane claims in commercials.......

ANd you know NOTHING about octane and detonation - I'd be willing to
bet significantly on that one. (Few people do - the myths on that
subject are - well - "mythical".

Don't get started on that one unless you want to get TOTALLY
buried......
>
>> There are standards, and there are standards. Any pad legitimately
>> sold in North America wilkl stop your unloaded $ Runner at legal
>> speeds under normal conditions. - For a while.
>
>Yup.
>That's the only logical conclusion anyone can make using Occam's Razor.

Why use Ocam's razor - don't you have your own????

Seriously - you are making more assumtions than I am - therefore the
chances of your conclusions being correct are significantly less than
mine.

Not quite sure you fully understand "Ockham's Razor" either (also
known as Occams razor - not Ocams) - a theory first postulated by a
14th century mathemetician and Franciscan Friar by the name of William
of Ockham as part of his "unified field theory"

His principal is simply "Entities should not be multiplied
unnecessarily."

It has been expanded on by many others includingsuch natables as
Einstein

Like any sharp instrument -Ockhams razor should not be weilded
blindly - - - -

On Tue, 16 Jan 2018 02:09:50 +0000 (UTC), Mad Roger
> wrote:

> On Mon, 15 Jan 2018 15:02:37 -0500,
> Clare Snyder wrote:
>
>> The tests were limited - addressing the use a cruiser puts the brakes
>> to. If you know how to read the information, it tells you a LOT about
>> the brakes - but you are correct - there is no "best" brake material -
>> it depends onthe use they are being put to, and what YOU want from
>> them. There may well , however, be " WORST" brakes.
>
>Exactly. You've been right all along while I was hoping beyond hope that
>there is an intelligent way to select a good/better/best brake pad.

>
>You were right. I was wrong.
>
>If you have two pads in your hands, or two on the net, you can't make an
>intelligent choice between them, other than to know if they're the same or
>not, and to know who made them, and to know what their cold and hot
>friction coefficients are.


If I know my application jolly right I can
>
>That's it.
>
>Each pad can be different - but you have no way of knowing that from the
>pad itself.
>
>> If brakes require higher pedal pressure to stop in a longer distance
>> (and decellerate at a lower rate) both when cold and at normal
>> temperature, and fade significantly on the second and third
>> application - they are pretty crappy brakes.
>
>Nobody complained about fade in that one report we have, did they?
>I don't think we have any better "fade" test than the Chase value for hot
>friction (which was E or F depending on the pads tested).

You obviously did not read and absorb the details of the michigan
test. All the brake fade data is clearly there if you know how to read
the report.
>
>So, while fade is important - it's a useless criteria since we have no way
>of knowing the fade.

i CAN TELL YOU which brake pad is going to fade the worst, just
knowing the COMPOSITION of the pad - organic, semi-metallic, or
ceramic - particularly between products from the same manufacturer.
WHos ceramic is beter than whos is a different story - -0 -
>
>It's just silly to bring up all the things that *can* happen if you have no
>way of choosing between them when the pads are in your very hands.
>
>I don't disagree with you that two pads can be vastly different, but you
>have no way of knowing anything other than their tested friction, their
>manufacturer, and whether two pads are exactly the same material.

I can know who made them and what market theyn are aimed at - which
gives me a lot more information than their 2 letter friction rating.
>
>That's all you've got since brands are almost meaningless (e.g., PBR, Axxis
>and Metalmasters are the same company) and semi-metallic/metalic/ceramic
>marketing is even more meaningless.

You are a total MORON

AXXIS and PBR ARE the same company, but a PBR or AXXIS Metalmaster is
NOT the same as a PBR or AXXIS Delux or Advanced Ceramic - but
PBR/AXXIS has more marketing BS than many companies.
>
>> If they require low pedal pressure to decellerate quickly to a stop in
>> a short distance when both cold and at normaltemperatures, AND do not
>> fade appreciably on the second and third (panic) stop - they are
>> pretty darn good brakes - anlness they squeal like a stuck pig, only
>> last for a month of driving, and/or destroy brake rotors - and/or coat
>> the wheels with nasty corrosive brake dust - - -
>
>All well and good, but it's like predicting that a baby will become the
>president of the United States.
>
>> No, not at all - you are TOTALLY missing the point.
>> The different brake PAD materials are mission specific.
>> A ceramic pad will outstop a economy organic pad when hot - hands
>> down. Every time.
>
>Let's just agree to disagree since you don't seem to realize what I know
>from talking to the Axxis marketing guy that the word 'ceramic' is a
>bull**** marketing term.

well, I know from dealing with brake application engineers and my
studies that "marketing guys" are generally like a dirty diaper.
>
>Do you think I don't call these marketing guys up?
>Do I seem like someone who doesn't ask pointed questions?

You seam like someone who doesan't know the questions to ask, doesn't
know when he's being snowed, and is so obvious that the marketing guys
know they can snow you and you won't know the difference. When you
need technical information you don't ask marketing - you ask
engineering - and you don't go in like a smartass - they can see right
through you.
>
>Ceramic is complete and total marketing bull****.
>The marketing guy told me himself.
>

The marketing guy doesn't know **** from shinola

>(Yes, I see the difficulty of position that puts me in.)
>
>> A metallic pad will usually stop better after several panic stops, or
>> when towing a heavy trailer down a longhill - than either the organic
>> or the ceramic. Both the semi metallic and the organic will stop
>> better on a cold stop than a ceramic.
>
>Let's agree to disagree.
>You believe in marketing.
>I don't.
>
>I believe in specifications.
>> No. a $85 Thermoquiet Ceramic will stop better than a $20 no-name
>> organic pad - and you can be pretty well assured you will not get a
>> $20 ceramic pad unless Rock Auto has something on clearout.
>
>Let's agree to disagree.

I'll agree to allow you to remain eternally clueless since you are
totally unteachable.
>
>You think price has some impact on performance.
>I will prove to you that I can show exact same products with different
>branding but the exact same price.

Just like a dirty diaper.

AXXIS delux pads are the same as PBR delux pads, but are NOT the
same as AXXIS or PBR Metalmasters - and "Metalmaster" is not a company
or resller - it is a "model" or "type" iof pad marketted by AXXIS , a
devision of PBR PLC in Australia.
>
>Everyone loves a number-line decision, whether it's good/better/best of
>metallic/semi-metallic/ceramic or $10/$20/$30 or 3-year/4-year-/5-year
>warranty, but none of that indicates a better or worse object.

A warranty is an insurance policy - not an indicator of quality. How
else do you explain a 10year warranty on the ****tiest cars to come
out of Japan - the Misu****ty. They can't sell their crap without a
10year warranty - and when the warranty is expired you can't sell one
- period.
>
>Only specifications do, and we just don't know much about the spec other
>than who made the pad, the code for the exact formulation, and the
>friction.
>
>Everything else is bull****.

Yad yada yada---------
>
>> Price is not a sure predictor of quality - but can be a pretty darn
>> good indicator.
>
>Price is an indicator of demand only. Demand is influenced by a ****load of
>factors. You know that. I know that. Let's not argue it. That's what
>Economics 101 was for, and I already took that and passed it.
>
>> Also, a high iron semi metallic WILL wear out your rotors faster than
>> either the organic or the ceramic unless the organic causes the rotor
>> to blister because of uneven pad material transfer, and abuse.
>
>If you truly know the "hardness", then of course it matters.
>But you have no way of knowing the hardness.
>Do you?

Sure I do
>
>> What you TOTALLY do NOT understand is how disc brakes, in particular,
>> work - and how the co-efficient of friction changes.
>
>I think I do understand how disc brakes work, but we can discuss what you
>think I don't understand.
>
>What I know is that your energy of movement has to be converted into
>something else, most notably heat. Lots and lots of heat.
>
>> When you "bed in" pads, you are burnishiung a thin coating of pad
>> material into the finish of the rotor..
>
>Yup. Pad deposition. Something about covalent bonds making and breaking
>under the heat of braking, where the breaking of the bonds elicits heat.
>
>It gets complex HOW the heat is generated (it's not just 'friction'), but
>the end result is heat. Lots and lots of heat.
>
>> The stopping power of the
>> brake depends on the co-efficient of friction between this burnished
>> in friction material and the pad - not between the pad and bare metal.
>
>The Ameca engineer already explained the burnished pads that the Michegan
>study used where he said it was to get rid of the volatile gases that come
>out of the first few heat cycles.

Well, he was WRONG.
>
>> How this coating is applied, and maintained, dictated the braking
>> charachteristics of a disc brake as much as anything.
>
>Yup. We all know how to property bed our brakes.
>I doubt many shops do it though, because it requires a lot of room and a
>few very hard almost stops where, if there is traffic, it ain't easy to do.
>
>I'll wager that few, if any, shops properly bed the pads.
>But you'd have that experience because I've never been to a mechanic.


>
>> If you stop hard
>> and fast and keep your foot onthe pedal at a stop untill the brake
>> cooles,there will be a heavier deposit on the rotor at that point -
>> UNLESS the padmaterial deposited on the rotor does not adhere properly
>> and it pulls away with the pad. Either way you will end up with uneven
>> braking - either a "thump" or a "skip" on the next brake application.
>
>NEVER, and I mean NEVER leave your foot on the pedal after a hard stop!
>Everyone knows this, so I know you know this.

Most certainly NOT everybody knows it.
>It's the worst thing you can do, unless you love to have judder every few
>thousand miles as that ped deposition collects more pad over time.
>
>I never understood why, but once a pad print, always a pad print.
>And it only gets worse.

Not neccesarily - If caught on time it is almost always reversible
>
>Unless you re-bed the brakes - which everyone knows - so you're preaching
>to the choir on even brake pad deposition techniques.
>
>> A "quality": pad will transfer evenly and bond reliably to the rotor
>> during the perscribed "bed-in" and will not cause uneven transfer
>> under "normal" driving conditions. It will also not cause or promote
>> corrosion between that pad mnaterial and the rotor steel (which causes
>> "scabbies" and pitted rotors (often mistaken for the less common, but
>> sometimes "real" "warped rotor".
>
>Yes. But. I have no good way of knowing a quality pad from a not quality
>pad. So it's moot.
>

You are a thickskulled and stubborn person - totally unteachable
>It's like me picking out the best students in a class based on whether they
>wear glasses or not.
>
>> Total bull****. The friction rating doesn't tell you much, but the
>> difference in required pedal pressure, and the difference in stopping
>> distance - notto mention the difference in pad temperature between the
>> best and worst in the test is VERY significant.
>
>It's significant in one thing. Pedal pressure.
>If pedal pressure is your gig - then it's significant.
>If pedal pressure isn't your gig, then it's not significant.
>
>The pedal pressure changed about 100%, from roughly less than ten foot
>pounds to less than twenty foot pounds in the lower-speed tests for
>example.
>
>What's 10 foot pounds?
>Dunno when it's pressing on a pedal, but if that's important, then you have
>to buy a police cruiser and put those pads on it - because it doesn't tell
>you anything about your car unless it's a police cruiser.
>
>> What is NOT significant is the predictabiklity of the results based
>> on the frictionrating of the pads under test. (almost totally useless)
>
>Yup. We agree. There is no useful data other than the AMECA code and even
>that isn't meant for the consumer.
>
>> And do your friend a favour and send them to a REAL mechanic to have
>> their brake work done. I fear you are DANGEROUS.
>


>Knowledge is dangerous.
>Logic is dangerous.
>Thinking is dangerous.
>
>Having someone else do all that for you, is dangerous.
>The mechanic doesn't give a **** about you or your brake pads.

WRONG - his livelihhod depends on it
>
>All the mechanic cares about is your money, and getting as much of that as
>possible, in the least time possible, so he'll skip steps like you can't
>believe.

Wrong. As a professional mechanic of long standing, with an
EXCELLENT reputation, I take that as a total affrront
>
>I'm on car forums where there are complaints galore about mechanics
>skipping half the steps in anything because they don't give a **** about
>anything but money.

I've seen the same forums - and most of the compainers are just as
dumb as you are.
>
>The only way to do it right is to do it yourself, is my motto.

You are free to do it yourself on your own car - although I don't
plan on being anywhere near you - but you should NOT be doing repairs
on other peoples vehicles - you are untrained, unauthorized, and
uninsured.

Anyone letting you work on their vehicles should be made aware of
that, and the dangers implied.

Ignorance is no excuse.
>
>You can disagree (and you almost certainly will), but you can't disagree
>that I'm trying to make an intelligent decision on which brake shoes to
>buy, and that I probably know them as well as any mechanic who *thinks* he
>knows them - but he doesn't - because he can't.
>

Well, you would be wrong.
>Nobody can but the guy who submitted them for their Chase test.

Wrong again.

PLONK

On Mon, 15 Jan 2018 16:31:56 -0500,
Clare Snyder wrote:

> a whole lot more!!!!!!!!!!!

I'm reading them as soon as I post this to let you know that...
Thanks for always posting on-topic technical value.

On Tue, 16 Jan 2018 08:45:56 -0800 (PST),
wrote:

>> I think price is not an indication of anything other than what the
>> marketing can make people pay. It's certainly not an indication of quality.
>
> that's true now

Yup. Basic Economics 101. Price is only a function of demand.

Price is never directly related to quality.
Price is only a function of demand.

Demand is a function of lots of complex variables, which is why they
invented Marketing (to greatly influence the demand).

>> I'm not sure what you mean by "scrapyards". To me, that means a junk yard,
>> which contains dead cars.
>
> same here

I can't imagine buying used brake shoes or pads off a scrapped car.
I just can't.

>> Are you talking about *used* brake pads or *new* brake pads?
>
> they're on cars, so used.'

Whoever proposes to buy brake pads and shoes off of junked cars is fine
with his logic, but he doesn't need to repeat it since it's not something
most of us would do.

I can see buying some parts at a scrap yard (e.g., a door or a fender), but
I just can't see buying a brake pad or shoe off a scrapped car.

How do you even do that? Do you walk around the junk yard to look for your
exact year, make and model and then pull the wheels and then pull the pads?

That's a lot of work, if you even find the right make and model, and then
if you can get to it (since they pile these things five cars high
sometimes) and if you can get the rusted lug bolts and brake drums off and
then you have to disassemble the brakes.

Seems like a *lot* of work for a brake shoe that will be "iffy" because you
have no way of knowing their condition ahead of time.

Or, maybe the junk yard does that for you, but then you are just staring at
a pile of brake shoes on the wall, which maybe, if you're lucky, have
accurate designations for the make and model of the vehicle they came off
of.

I guess if you bring your old shoes with you, you can match them, but that
means your car is on blocks the whole time you do this, so you have to have
a second vehicle to do it.

I just don't see *how* it's practicable.
Do you?

On Tue, 16 Jan 2018 08:45:56 -0800 (PST),
wrote:

>> I think price is not an indication of anything other than what the
>> marketing can make people pay. It's certainly not an indication of quality.
>
> that's true now

Yup. Basic Economics 101. Price is only a function of demand.

Price is never directly related to quality.
Price is only a function of demand.

Demand is a function of lots of complex variables, which is why they
invented Marketing (to greatly influence the demand).

>> I'm not sure what you mean by "scrapyards". To me, that means a junk yard,
>> which contains dead cars.
>
> same here

I can't imagine buying used brake shoes or pads off a scrapped car.
I just can't.

>> Are you talking about *used* brake pads or *new* brake pads?
>
> they're on cars, so used.'

Whoever proposes to buy brake pads and shoes off of junked cars is fine
with his logic, but he doesn't need to repeat it since it's not something
most of us would do.

I can see buying some parts at a scrap yard (e.g., a door or a fender), but
I just can't see buying a brake pad or shoe off a scrapped car.

How do you even do that? Do you walk around the junk yard to look for your
exact year, make and model and then pull the wheels and then pull the pads?

That's a lot of work, if you even find the right make and model, and then
if you can get to it (since they pile these things five cars high
sometimes) and if you can get the rusted lug bolts and brake drums off and
then you have to disassemble the brakes.

Seems like a *lot* of work for a brake shoe that will be "iffy" because you
have no way of knowing their condition ahead of time.

Or, maybe the junk yard does that for you, but then you are just staring at
a pile of brake shoes on the wall, which maybe, if you're lucky, have
accurate designations for the make and model of the vehicle they came off
of.

I guess if you bring your old shoes with you, you can match them, but that
means your car is on blocks the whole time you do this, so you have to have
a second vehicle to do it.

I just don't see *how* it's practicable.
Do you?

On Tue, 16 Jan 2018 08:52:07 -0800 (PST),
wrote:

> not really. But cars generally seem to deal with it ok.
> Ultimately it comes down to enough force to create enough
> friction, and almost any friction material can do that.

I agree with your logical thought process in that the only scientific
summary that makes logical sense is that all pads work just fine in
passenger vehicles, with the main difference being the foot pounds of
torque applied to the brake pedal to obtain the desired deceleration rate.

Hence, any pad is fine, EE or FF or GG, for stopping the vehicle.

> I certainly bought bad pads in about 2000.
I go though a set of front pads once every couple of years, never more than
two years on my own vehicle, but on this vehicle, it took 20 years to go
through one set of rear shoes.

> The ones from the scrapyard OTOH I had no problem with.

The problem isn't the scrapyard per se.
The problem is getting the *right* pads at the scrapyard.
That can't be easy (see my other post on how that's done).

> Those I got to see after they'd been used a bit, so I knew they
> weren't disintegrating, let alone badly, or oily.

What does that even mean?

> You criticised buying pads off scrap vehicles before, but truth
> is every time you buy a used car you're getting used brake pads.
> It's not a problem really.

I don't at all disagree with your apropos logic that every time you buy a
used car you get used pads, but, you can assume (logically) that the pads
fit.

I've been to junk yards where there literally are junked cars piled four
and five cars high outdoors, where you walk the yard looking for the fender
or mirror that you want.

To look for brake pads would be an order of magnitude harder because you
can't see the brake pad until you find a similar vehicle make model and
year, you climb up to the top car, you remove the wheels, you pull the
rusty drums or calipers off, and then, only then, do you get any chance to
see the condition of the brake pads and shoes.

Or, if the scrapyard does all that for you, and has placed a ton of brake
shoes on the shelves, you can pick among them for the right size and shape,
but that process comes with the problem that you have to have a comparison
pad and shoe in your hands, which means your car is up on blocks and you're
borrowing someone else's car.

If you can read the AMECA edge code, you have a chance at getting the right
shoe or pad, but it sure does seem like a lot of effort when an FF pad or
shoe is about $20 a set of four at Rock Auto.

Did I surmise the scrap yard process incorrectly?
If so, how would you correct that process of *selecting* the right pads?

On Mon, 15 Jan 2018 09:43:16 -0800 (PST),
trader_4 wrote:

> This whole thing seems a bit silly to me. It's a test for police
> cars. I would expect that all cars can lock the wheels with a
> power assisted force that's well within the range that a typical
> driver can apply. That's one of the reasons we went to anti-lock
> brakes, right? Because once it's locked, you need to release force
> to keep it moving to keep control. So, why police would be so worried
> about how much force it takes on the pedal, IDK. ARe they such wusses
> that they can't apply reasonable force that would lock the wheels
> in panic situations? Those force numbers required are all within what
> any cop that's fit for duty can apply. So, what's the point?
> I agree with Clare, there are plenty of other issues here that are
> more important than the friction. IMO, unless it's some unusual
> situation, this friction thing is mostly a red herring in selecting
> brake pads.

I removed s.e.r so I didn't see this post until moving over to a.h.r, so I
apologize for not having prior responded.

I agree with you on pedal force, where we must note that the range was from
about 8 foot pounds to about 30 foot pounds, from a slow deceleration to a
panic stop, which I presume we're all able to supply.

I'm not defending the police report but they did mention that women are in
the force now, and they mentioned that they cruise all day, but still, I'm
with you on the pedal force.

To their credit, the pedal force *does* equate to stopping distance, where
only the 30 foot pound panic stop test actually stops in the *shortest*
distance possible.

Fundamentally, what they found was that the pedal force between any two
pads (all were either EE or FF) varied by about 10 foot pounds (give or
take) to keep to a given deceleration, which, I'm guessing, isn't all that
much of a difference that is meaningful to us.

Still ... it's the best test we could find, so if you can find a better
test, we'd be all ears.

As for your last comment that 'friction is a red herring', I can't
logically disagree (given the facts we've unearthed), but intuitively I
would have *assumed* that friction was of primary importance in brake
friction materials.

Given that intuition fails in this case, it's one reason why I say that
most people who *only* rely on intuition are more often wrong than right,
because in this situation, clearly, friction isn't of primary importance in
brake friction material performance.

Who knew.
Only Clare.
Certainly not I.

On Mon, 15 Jan 2018 09:54:26 -0800 (PST),
trader_4 wrote:

> Bingo. Cops are supposed to be reasonably physically fit. We went
> to anti-lock brakes because the regular drivers were locking the breaks.

Somewhere I read that ABS doesn't stop you in the shortest distance - it
just stops you with the most control. Dunno if that's true as that's not
what I was aiming for here.

> I've never had a car with any brake pads where I could not very easily
> with limited force, lock the brakes. So, why the obsession with the
> coefficient of friction?

It's not so much an obsession with any one spec but the desire to be able
to intelligently compare two brake shoes that are in one's hand or on the
web.

It should be clear by now that I don't trust salesmen or marketing, so I'm
pretty much stuck to trusting whatever specs we have.

And we *know* that the AMECA Edge Code is one spec that must, by law, be
printed on every shoe.

> For the typical driver, how much brake dust
> they put out is more of an issue.

I agree that there are other important criteria of a second-order nature
other than how well a shoe stops.

But just stating them doesn't help.

We have to be able to tell how much shoe A dusts compared to shoe B when we
go to the parts store or on the web to buy them.

How do YOU tell if shoe A dusts more or less than shoe B for example?

> I can see the coefficient of friction
> affecting how they feel, whether you need to put X force that;s within
> your ability to lock them, or X plus some force that's still well within
> your ability to lock them, but that's all.

It doesn't even seem to do that, since as Clare noted, EE and FF brakes had
pedal forces to maintain a given deceleration that were 100% different and
it didn't matter whether they were EE or FF. It was dependent on the pad.

So, we're really stuck with nothing.

As you noted, *lots* of things are important, but that's meaningless if we
can't tell, with the shoes in our hand or on the web, which ones are better
than the others.