On 2022-05-14 6:25 a.m., Andy Burnelli wrote:
> sms wrote:
>
>> Andy Burnelli can learn about rotors and resurfacing here:
>
> Steve,
> You make something as simple as a spec into some kind of voodoo magic.
>
> Every statement from you shows you have _never_ done a proper brake job in
> your entire life, which is why you posted total bullshit about rotor warp.
>
> Rotors don't warp.
> They can't.
> You need in excess of 2300 degrees F (brake fluid boils at 1/4 that temp!).
> The brake system would be marshmallows by the time rotors got hot enough.

<https://www.youtube.com/shorts/fFY2MPylrS4>

On 2022-05-14 6:30 a.m., Andy Burnelli wrote:
> Xeno wrote:
>
>>> I have only about a half dozen old rotors in my garage in a heap.
>>> They're useful for weights, but I was hoping to find a use for them.
>>
>> Recycle them - scrap iron.
>
> Hi Xeno,
>
> I assess you as the most knowledgeable here (certainly you have more
> experience than I do); however I will point out you dodged both issues.
>
> 1. You dodged the issue that brake rotors can't possibly warp
>   simply because the 2300 degrees needed would make the rest
>   of the components disintegrate (e.g., brake fluid boils at
>   less than 1/4 of that temperature - and you know this).

<https://www.youtube.com/shorts/fFY2MPylrS4>

Xeno wrote:

>> On _that_ topic alone, have you ever seen a typical rotor "gouge" spec?
>
> Can't recall.

Don't worry.
I knew the answer before I asked it of you.

> I just looked at the rotor gouge and, if *I* considered it
> too deep, into the bin it went.

I understand.
I know all about what people do.

> You have to realise that *any gouge*
> reduces the surface area for braking so if it doesn't machine out, it
> will take ages for the pads to fully bed, if at all, and will lead to
> unbalanced braking if the gouges on each side of the car aren't balanced.

It's a basic question I ask of everyone who claims to measure rotors.
They never even _know_ what the gouge spec is.

>> I have.
>> That spec is often hard to find, but when found, it's shocking (to me).
>> The first is that the spec allows _huge_ gouges (imho).
>
> I use my own judgement.

Trust me, I know what you're going to say on rotors before you do.

So don't worry.
I expected it.

>> And the second is I've never seen a rotor _that_ gouged.
>
> I have seen terribly gouged rotors - and I've binned them.

I have only replaced my own rotors (and that of my family), where I haven't
yet had to bin a rotor for anything other than for it being too thin.

BTW, you got the reason rotor thickness matters wrong too, but that's OK.
Everyone gets that wrong too, so I won't hold it against you.

>> No big deal. I'd junk any rotor that doesn't meet spec w/o a second thought
>> since a rotor is a safety item that costs only about $15 to $35 per wheel.
>
> Pre-cisely!

As I said, there is only one "proper" way to decide if a rotor needs to be
replaced, and it's _not_ what Steve said (he said every pad replacement or
every other pad - but that's just bullshit from people who talk bullshit).

Rest assured I know a _lot_ of morons out there say exactly what Steve does
but when you ask them the kinds of questions I've been asking you, they
fail the test instantly.

>> My question to you are the two above:
>> a. Have you seen how (seemingly) huge a gouge has to be to fail spec?
>
> Again, I use my own judgement.

I know. I knew that before I asked you.
Next time you work on rotors, ask the manufacturer for the spec.

My prediction is you'll be shocked at how huge a gouge has to be to fail.

>> b. How often have _you_ seen a rotor gouged enough to fail that spec?
>
> I have had heaps of rotors, and drums, fail my judgemental spec.

If they meet specs, I generally re-use them (unless they're for someone
else, and then, in that case, I often replace good rotors anyway, since I
don't know what kind of maintenance they will do in the future).

Luckily, in the USA, as long as you meet or exceed OEM specs, we can't get
an unsafe rotor, and we can't get an unsafe brake pad, nor an unsafe tire
(notwithstanding one-of-a-kind fuckups like the Firestone one of course).

But we can pay $50 per axle for crappy pads (e.g., EE) and we can pay $50
each for rotors (there are no crappy rotors), and we can pay $200 for
crappy tires (there are no unsafe tires), etc., if we don't know what we're
doing (or, more to the point, if we think "we get what we pay for").

In my humble experience, typical sedan & SUV rotors are something like $15
to $35 each, and typical FF or GG or even HH pads are about the same per
axle, and V-rated appropriate load index tires are almost always somewhere
around $75 to $100 each (depending of course on the size & type of tire).

On 5/14/2022 8:30 AM, Andy Burnelli wrote:
> Xeno wrote:
>
>>> I have only about a half dozen old rotors in my garage in
>>> a heap.
>>> They're useful for weights, but I was hoping to find a
>>> use for them.
>>
>> Recycle them - scrap iron.
>
> Hi Xeno,
>
> I assess you as the most knowledgeable here (certainly you
> have more
> experience than I do); however I will point out you dodged
> both issues.
>
> 1. You dodged the issue that brake rotors can't possibly warp
> simply because the 2300 degrees needed would make the rest
> of the components disintegrate (e.g., brake fluid boils at
> less than 1/4 of that temperature - and you know this).
>
> 2. You dodged the issue that you fail a brake rotor on one
> condition and one condition only - which is if it no longer
> meets the spec.
>
> On the specific spec of gouge depth and width, I also
> noticed you dodged
> that, which tells me you've never looked at a spec sheet in
> your life.
>
> Don't feel badly about that.
> Almost nobody does.
>
> Everyone _says_ they do.
> But they lie.
>
> Like you did.
> And that's OK.
>
> I'm not _expecting_ anyone here to know what I know about
> brakes.
> Not even you, even as I defer to your mass of experience
> over mine.
>
> I just tell it like it is.
> Most people bullshit.

Differential thermal expansion does not require entering the
plastic zone for the entire piece.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

AMuzi wrote:

> Differential thermal expansion does not require entering the
> plastic zone for the entire piece.

Finally someone on this newsgroup is using their brain.

It's disconcerting that most people completely ignored the dozen references
I provided and that they provided, in turn, a 20-second youtube from a kid
in NJ which shows absolutely nothing whatsoever - and yet they think it
does.

They may as well claim the earth is flat in a 20 second video from a kid in
NJ who _proves_ it beyond any doubt in their (strange) low-IQ brains.

Anyway, Amuzi brings up an _excellent_ point that you don't likely need the
2300 degrees it takes to _begin_ melting a typical cast iron rotor.

But bear in mind even the best brake fluid boils off at well under one
quarter of that temperate, and that the rubber in the braking system would
be marshmallows anywhere near the "zone of thermal expansion" Amuzi alludes
to, and we have what appears to be a situation which requires more data.

At what temperature does a rotor 'soften' is key here, I think, isn't it?
Isn't that what Amuzi is alluding to?

Certainly if you leave the rotors on a steel rack at a thousand degrees for
ten hours (which we learned in the paper Vic Smith referenced), they will
"increase" their "distortion"; so I _believe_ what Amuzi is alluding to.

However, nobody here is going to claim that their rotors spent ten hours at
a thousand degrees and _then_ they declared that they warped, right?

The brake system components (piston gaskets, fluid lines, fluid, etc.)
would be marshmallows at even the "low" temperature of a thousand degrees.

In summary, I get it that people _believe_ their rotors warped, and yet,
I've _never_ seen anyone who said that who actually _measured_ it, and,
worse, I found a dozen experts who claim it's impossible given the
temperature required is greater than the brake system can handle.

If Amuzi is correct that warp (aka "thermal distortion") happens at a lower
temperature than a thousand degrees for ten hours, then I'm all ears.

Give me a fact, and I'll read it.
Does anyone have any reliable cites that back up their belief system?
--
And no, a 20 second video of a kid in NJ making claims is not reliable.

On 2022-05-15 2:36 p.m., Andy Burnelli wrote:
> AMuzi wrote:
>
>> Differential thermal expansion does not require entering the plastic
>> zone for the entire piece.
>
> Finally someone on this newsgroup is using their brain.
>
> It's disconcerting that most people completely ignored the dozen references
> I provided and that they provided, in turn, a 20-second youtube from a kid
> in NJ which shows absolutely nothing whatsoever - and yet they think it
> does.
>
> They may as well claim the earth is flat in a 20 second video from a kid in
> NJ who _proves_ it beyond any doubt in their (strange) low-IQ brains.
>
> Anyway, Amuzi brings up an _excellent_ point that you don't likely need the
> 2300 degrees it takes to _begin_ melting a typical cast iron rotor.
>
> But bear in mind even the best brake fluid boils off at well under one
> quarter of that temperate, and that the rubber in the braking system would
> be marshmallows anywhere near the "zone of thermal expansion" Amuzi alludes
> to, and we have what appears to be a situation which requires more data.
>
> At what temperature does a rotor 'soften' is key here, I think, isn't it?
> Isn't that what Amuzi is alluding to?
>
> Certainly if you leave the rotors on a steel rack at a thousand degrees for
> ten hours (which we learned in the paper Vic Smith referenced), they will
> "increase" their "distortion"; so I _believe_ what Amuzi is alluding to.
>
> However, nobody here is going to claim that their rotors spent ten hours at
> a thousand degrees and _then_ they declared that they warped, right?
>
> The brake system components (piston gaskets, fluid lines, fluid, etc.)
> would be marshmallows at even the "low" temperature of a thousand degrees.
>
> In summary, I get it that people _believe_ their rotors warped, and yet,
> I've _never_ seen anyone who said that who actually _measured_ it, and,
> worse, I found a dozen experts who claim it's impossible given the
> temperature required is greater than the brake system can handle.
>
> If Amuzi is correct that warp (aka "thermal distortion") happens at a lower
> temperature than a thousand degrees for ten hours, then I'm all ears.
>
> Give me a fact, and I'll read it.
> Does anyone have any reliable cites that back up their belief system?

How about videos of warped rotors?

Will those do?

Andy Burnelli wrote:

> If Amuzi is correct that warp (aka "thermal distortion") happens at a lower
> temperature than a thousand degrees for ten hours, then I'm all ears.
>
> Give me a fact, and I'll read it.
> Does anyone have any reliable cites that back up their belief system?

I realized belatedly that I didn't point out that the temperature it takes
to "soften" rotors only has to be "locally" applied for what Amuzi is
hypothesizing to occur, to occur.

So, for example, you can perhaps get to the 2300 degrees it takes to begin
softening rotors locally, but bear in mind rotors are _designed_ to cool
off, so it's not going to be easily done, if it's even possible to be done.

I get it that almost everyone trusts their intuition more than they will
ever trust in facts, where I repeat I know Quantum Mechanics, where
_nothing_ is intuitive. Trust me on that.

We humans own the intuition of monkeys.
That serves us well sometimes - but it serves us poorly most of the time.

The reason it serves us poorly is that, sure, it "sounds good" that rotors
would warp, especially when most of the time replacing or machining the
rotors "solves" the warp, so, to most morons, it's intuitive it warped.

But the facts remain that you need an astoundingly huge temperature,
whether applied locally or not, to force a rotor to deform like that.

The brake system can't handle that temperature.

There are a few reasons for that, one of which is it never happens, but the
more important reason is that the system is _designed_ to cool itself off.

What I'm fighting here is the fact I'm not used to dealing with the hoi
polloi who believe in a 20 second YouTube video of basically nothing,
without even _reading_ the dozen or so reliable reference links I cited.

I'm not saying Amuzi is wrong, by the way - since his premise is valid that
locally, the deformation temperature point might be reached in a typical
braking system under duress...

But what we need now is _science_ backing up his supposition.
If you post it, I'll read it.

More to the point, as with Vic Smith's reference, if I read it, I'll at
least grasp what it says (using basic adult cognitive skills God gave me).
--
That's what separates me from the morons.

On 2022-05-15 2:46 p.m., Andy Burnelli wrote:
> Andy Burnelli wrote:
>
>> If Amuzi is correct that warp (aka "thermal distortion") happens at a
>> lower
>> temperature than a thousand degrees for ten hours, then I'm all ears.
>>
>> Give me a fact, and I'll read it.
>> Does anyone have any reliable cites that back up their belief system?
>
> I realized belatedly that I didn't point out that the temperature it takes
> to "soften" rotors only has to be "locally" applied for what Amuzi is
> hypothesizing to occur, to occur.

Metals don't need to "soften" to undergo change due to relief of stress.

On 5/15/2022 4:36 PM, Andy Burnelli wrote:
> AMuzi wrote:
>
>> Differential thermal expansion does not require entering
>> the plastic zone for the entire piece.
>
> Finally someone on this newsgroup is using their brain.
>
> It's disconcerting that most people completely ignored the
> dozen references
> I provided and that they provided, in turn, a 20-second
> youtube from a kid
> in NJ which shows absolutely nothing whatsoever - and yet
> they think it
> does.
>
> They may as well claim the earth is flat in a 20 second
> video from a kid in
> NJ who _proves_ it beyond any doubt in their (strange)
> low-IQ brains.
>
> Anyway, Amuzi brings up an _excellent_ point that you don't
> likely need the
> 2300 degrees it takes to _begin_ melting a typical cast iron
> rotor.
>
> But bear in mind even the best brake fluid boils off at well
> under one
> quarter of that temperate, and that the rubber in the
> braking system would
> be marshmallows anywhere near the "zone of thermal
> expansion" Amuzi alludes
> to, and we have what appears to be a situation which
> requires more data.
>
> At what temperature does a rotor 'soften' is key here, I
> think, isn't it?
> Isn't that what Amuzi is alluding to?
>
> Certainly if you leave the rotors on a steel rack at a
> thousand degrees for
> ten hours (which we learned in the paper Vic Smith
> referenced), they will
> "increase" their "distortion"; so I _believe_ what Amuzi is
> alluding to.
>
> However, nobody here is going to claim that their rotors
> spent ten hours at
> a thousand degrees and _then_ they declared that they
> warped, right?
>
> The brake system components (piston gaskets, fluid lines,
> fluid, etc.)
> would be marshmallows at even the "low" temperature of a
> thousand degrees.
>
> In summary, I get it that people _believe_ their rotors
> warped, and yet,
> I've _never_ seen anyone who said that who actually
> _measured_ it, and,
> worse, I found a dozen experts who claim it's impossible
> given the
> temperature required is greater than the brake system can
> handle.
>
> If Amuzi is correct that warp (aka "thermal distortion")
> happens at a lower
> temperature than a thousand degrees for ten hours, then I'm
> all ears.
>
> Give me a fact, and I'll read it.
> Does anyone have any reliable cites that back up their
> belief system?

Brake pads are thermal insulators so whatever is going on at
the rotor doesn't necessarily melt rubber bits or boil brake
fluid. There's also ample airflow and space between rotor
and other components. Even brake shoe holders have minimal
contact with calipers.

Also, out in the world, boiling brake fluid is virtually
unknown but warped rotors, while not commonplace, are
regularly noted in brake service.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On 5/15/2022 4:36 PM, Andy Burnelli wrote:
> AMuzi wrote:
>
>> Differential thermal expansion does not require entering
>> the plastic zone for the entire piece.
>
> Finally someone on this newsgroup is using their brain.
>
> It's disconcerting that most people completely ignored the
> dozen references
> I provided and that they provided, in turn, a 20-second
> youtube from a kid
> in NJ which shows absolutely nothing whatsoever - and yet
> they think it
> does.
>
> They may as well claim the earth is flat in a 20 second
> video from a kid in
> NJ who _proves_ it beyond any doubt in their (strange)
> low-IQ brains.
>
> Anyway, Amuzi brings up an _excellent_ point that you don't
> likely need the
> 2300 degrees it takes to _begin_ melting a typical cast iron
> rotor.
>
> But bear in mind even the best brake fluid boils off at well
> under one
> quarter of that temperate, and that the rubber in the
> braking system would
> be marshmallows anywhere near the "zone of thermal
> expansion" Amuzi alludes
> to, and we have what appears to be a situation which
> requires more data.
>
> At what temperature does a rotor 'soften' is key here, I
> think, isn't it?
> Isn't that what Amuzi is alluding to?
>
> Certainly if you leave the rotors on a steel rack at a
> thousand degrees for
> ten hours (which we learned in the paper Vic Smith
> referenced), they will
> "increase" their "distortion"; so I _believe_ what Amuzi is
> alluding to.
>
> However, nobody here is going to claim that their rotors
> spent ten hours at
> a thousand degrees and _then_ they declared that they
> warped, right?
>
> The brake system components (piston gaskets, fluid lines,
> fluid, etc.)
> would be marshmallows at even the "low" temperature of a
> thousand degrees.
>
> In summary, I get it that people _believe_ their rotors
> warped, and yet,
> I've _never_ seen anyone who said that who actually
> _measured_ it, and,
> worse, I found a dozen experts who claim it's impossible
> given the
> temperature required is greater than the brake system can
> handle.
>
> If Amuzi is correct that warp (aka "thermal distortion")
> happens at a lower
> temperature than a thousand degrees for ten hours, then I'm
> all ears.
>
> Give me a fact, and I'll read it.
> Does anyone have any reliable cites that back up their
> belief system?

further to my recent comments:
http://forums.pelicanparts.com/uploads20/REDHOTBR+7001334174918.jpg

Note relatively significant heat isolation of rotor braking
surface as compared to caliper, brake lines, wheel bearing etc.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On 5/15/2022 4:52 PM, AMuzi wrote:

<snip>

> Note relatively significant heat isolation of rotor braking surface as
> compared to caliper, brake lines, wheel bearing etc.

Exactly. The idea that brake fluid would boil because the rotors got hot
displays a profound cluelessness about how vehicle braking systems function.

On 16/5/2022 7:46 am, Andy Burnelli wrote:
> Andy Burnelli wrote:
>
>> If Amuzi is correct that warp (aka "thermal distortion") happens at a
>> lower
>> temperature than a thousand degrees for ten hours, then I'm all ears.
>>
>> Give me a fact, and I'll read it.
>> Does anyone have any reliable cites that back up their belief system?
>
> I realized belatedly that I didn't point out that the temperature it takes
> to "soften" rotors only has to be "locally" applied for what Amuzi is
> hypothesizing to occur, to occur.
>
> So, for example, you can perhaps get to the 2300 degrees it takes to begin
> softening rotors locally, but bear in mind rotors are _designed_ to cool
> off, so it's not going to be easily done, if it's even possible to be done.
>
> I get it that almost everyone trusts their intuition more than they will
> ever trust in facts, where I repeat I know Quantum Mechanics, where
> _nothing_ is intuitive. Trust me on that.

When people say *trust me*, it is far wiser to do the opposite.
>
> We humans own the intuition of monkeys.

You might, I don't. One of the things I do is *test* any *theory* I come
up with. Is the rotor warped? Intuition might tell you, my measurements
tell me what the reality is *on the ground*. I spent decades teaching
apprentices to *test* any diagnosis theories (or intuition) they come up
with. Never assume, just measure.

> That serves us well sometimes - but it serves us poorly most of the time.
>
> The reason it serves us poorly is that, sure, it "sounds good" that rotors
> would warp, especially when most of the time replacing or machining the
> rotors "solves" the warp, so, to most morons, it's intuitive it warped.

But to us *mechanics* who actually *measure the warp*, it is no longer
*intuitive*, it's *proven fact*. Facts are good.
>
> But the facts remain that you need an astoundingly huge temperature,
> whether applied locally or not, to force a rotor to deform like that.

Rotors never heat *uniformly*. In fact, it is the outer periphery that
will heat the most and it is the outer periphery that will begin to
deform first.
>
> The brake system can't handle that temperature.
>
> There are a few reasons for that, one of which is it never happens, but the
> more important reason is that the system is _designed_ to cool itself off.

Well done, and the cooling is *never even*.
>
> What I'm fighting here is the fact I'm not used to dealing with the hoi
> polloi who believe in a 20 second YouTube video of basically nothing,
> without even _reading_ the dozen or so reliable reference links I cited.

I don't consider myself to be a member of the hoi polloi and, in direct
contrast, I have seen and measured many such warped rotors as depicted
in the video. And, as in the video, I have *machined* countless rotors
*with warp* and measured, seen, heard and *felt* the same effects as
shown in that video and so many others.
>
> I'm not saying Amuzi is wrong, by the way - since his premise is valid that
> locally, the deformation temperature point might be reached in a typical
> braking system under duress...
> But what we need now is _science_ backing up his supposition.
> If you post it, I'll read it.
>
> More to the point, as with Vic Smith's reference, if I read it, I'll at
> least grasp what it says (using basic adult cognitive skills God gave me).

You screwed yourself on that last sentence.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 16/5/2022 7:36 am, Andy Burnelli wrote:
> AMuzi wrote:
>
>> Differential thermal expansion does not require entering the plastic
>> zone for the entire piece.
>
> Finally someone on this newsgroup is using their brain.
>
> It's disconcerting that most people completely ignored the dozen references
> I provided and that they provided, in turn, a 20-second youtube from a kid
> in NJ which shows absolutely nothing whatsoever - and yet they think it
> does.
>
> They may as well claim the earth is flat in a 20 second video from a kid in
> NJ who _proves_ it beyond any doubt in their (strange) low-IQ brains.
>
> Anyway, Amuzi brings up an _excellent_ point that you don't likely need the
> 2300 degrees it takes to _begin_ melting a typical cast iron rotor.
>
> But bear in mind even the best brake fluid boils off at well under one
> quarter of that temperate, and that the rubber in the braking system would
> be marshmallows anywhere near the "zone of thermal expansion" Amuzi alludes
> to, and we have what appears to be a situation which requires more data.
>
> At what temperature does a rotor 'soften' is key here, I think, isn't it?
> Isn't that what Amuzi is alluding to?
>
> Certainly if you leave the rotors on a steel rack at a thousand degrees for
> ten hours (which we learned in the paper Vic Smith referenced), they will
> "increase" their "distortion"; so I _believe_ what Amuzi is alluding to.
>
> However, nobody here is going to claim that their rotors spent ten hours at
> a thousand degrees and _then_ they declared that they warped, right?
>
> The brake system components (piston gaskets, fluid lines, fluid, etc.)
> would be marshmallows at even the "low" temperature of a thousand degrees.
>
> In summary, I get it that people _believe_ their rotors warped, and yet,
> I've _never_ seen anyone who said that who actually _measured_ it, and,

You are being deliberately disingenuous here! I have told you that I
have *measured* warped rotors. It is very easy to prove that a rotor has
warped, all you need is a dial indicator with a magnetic base. You
measure the face and find the *low point*, mark it. Then you find the
*high* point, mark it and include the measurement. Use zero as the
reference datum for the low point. Then measure the obverse face of the
rotor in the same manner. If the zero reference on one side matches the
high side on the obverse, you have a *warped rotor*. You can do further
checks to ensure that something else is not causing the effect, the dial
indicator will serve for that purpose as well.

BTW, have you spent *any time* in an engineering shop at all?

> worse, I found a dozen experts who claim it's impossible given the
> temperature required is greater than the brake system can handle.
>
> If Amuzi is correct that warp (aka "thermal distortion") happens at a lower
> temperature than a thousand degrees for ten hours, then I'm all ears.

Irrelevant to the situation that occurs in a brake rotor. You are making
incorrect assumptions, bullshit assumptions in fact.
>
> Give me a fact, and I'll read it.

I have given you facts, they don't match your *belief system* so you
diss them out of hand.

> Does anyone have any reliable cites that back up their belief system?

I have been there, measured warped rotors. Your voodoo science doesn't
match the *reality* in which I live. That is a problem for you, not me.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

AMuzi wrote:

> further to my recent comments:
> http://forums.pelicanparts.com/uploads20/REDHOTBR+7001334174918.jpg

Destructive testing has its place in terms of gathering scientific data.

That situation was artificially created on a special "test jig for brakes"
by Porsche as shown here <https://seinesystems.com/BrakeFade.htm>
"Yellow color indicates rotor surface temperature of approximately 2000�F.
Fresh, heavy duty brake fluid boils at around 450-550�F."
Copyright 1997 Porsche Cars North America, Inc."

Nobody is saying you can't run an engine with the brakes held for what
constitutes dozens of miles continuously at 150mph & the rotors get red.
<https://www.pinterest.com/pin/glowing-exhaust-page-2-pelican-parts-technical-bbs--419819996486878798/>

Bugati did it here, for example at continuous speeds over 150 mph with the
calipers locked for minutes on end while measuring temperature & speed.
<https://youtu.be/QIc-9UuLSmg?t=161>

I _love_ destructive testing.
In fact, purposefully destructive testing is a wonderful thing to watch.

"We doctored the rotor to get it red hot to subject it to rapid cooling."
https://youtu.be/B6UM4P1c8mA?t=789
Sparks. Fire. Multiple dousing with water. Cracks galore.
Even the brake pads were melted and misshapen after that torture test.
Just like the reliable references I provided said would happen.

See also:
<https://rob928.home.xs4all.nl/928info/_home.htm>
<http://forums.pelicanparts.com/porsche-911-technical-forum/639508-glowing-exhaust-2.html>
<https://www.r3vlimited.com/board/forum/general-forums/general-discussion/9945-red-hot-brakes#post568873>

sms wrote:

>> Note relatively significant heat isolation of rotor braking surface as
>> compared to caliper, brake lines, wheel bearing etc.
>
> Exactly. The idea that brake fluid would boil because the rotors got hot
> displays a profound cluelessness about how vehicle braking systems function.

It's kind of interesting how _desperate_ you have become given not a single
one of you read even a single one of the references already provided.

All you "can" do is point to a special Porsche destructive testing jig.

You do realize that rotor was run on a special test jig that purposefully
ran at a simulated speed of 150 mph continuously with the calipers locked.

The pads were destroyed.
The rubber was on fire.
The fluid boiled.
The rotors were cracked.

Just as the references said they would be.

Think about the _logic_ here, in your _desperation_ to back up your
imaginary belief system.

If you can't get rotors _that_ hot without _tremendous_ damage to the
braking system components, how do people who claim their rotors warp
"justify" that their pads and fluid and rubber is just fine.

Doesn't anyone here own a synapse that can explain that obvious fatal flaw
in their argument?

Xeno wrote:

> I have given you facts, they don't match your *belief system* so you
> diss them out of hand.

Find even a _single_ reliable reference that backs up your claims.

And I'll read it.

Find just one.

Xeno wrote:

> You are being deliberately disingenuous here!

I can tell you're getting desperate because you have no defense to facts.
You're acting just like Putin where you accuse me of what _you_ are doing.

FACT:
a. I gave you a dozen reliable references; none of which you read.
b. You gave me zero.

Who is being disingenuous here, Xeno.
a. I backed up my claims with reliable references.
b. You didn't.

But you can turn me around on a dime.
I'm easy to convince with facts.

Just "saying" you measured warp isn't going to work since I've heard people
say that for decades and not one of them ever knew that the temperatures
required would turn a braking system into mush.

Provide me even a _single_ reliable reference that says what you say, which
is that people "think" rotors don't warp and yet they do.
*Find just one*

Without even a _single_ reliable reference backing up your claim, it's you
who is being disingenuous. Not me.

Note: I am well aware you can find a billion bullshit web pages selling new
rotors that will "claim" the rotors warped so find a _reliable_ cite, like
I did, from _experts_ who aren't selling anything but just telling the
facts.

Remember, a rotor will crack before it will warp.
--
HINT: If the reference doesn't speak of the facts with temperatures, then
it's not reliable because without high temperature, you can't get warp.

On 16/5/2022 3:45 pm, Andy Burnelli wrote:
> Xeno wrote:
>
>> You are being deliberately disingenuous here!
>
> I can tell you're getting desperate because you have no defense to facts.
> You're acting just like Putin where you accuse me of what _you_ are doing.

Me? Desperate? You must be joking? FWIW, Putin is a *liar*.
>
> FACT:
> a. I gave you a dozen reliable references; none of which you read.
> b. You gave me zero.

I gave you the one I value most, my direct experience.
>
> Who is being disingenuous here, Xeno.
> a. I backed up my claims with reliable references.
> b. You didn't.

I backed up my claim with reference to what I saw and did whilst working
at my trade. My direct experience. Yes, I worked in the industry and
have *hands on* experience with warped rotors. I have seen them, I have
measured them, I have, where possible, even cleaned them up to
serviceable condition. Your *experience* with brakes is limited to hobby
repairs at home.
>
> But you can turn me around on a dime.
> I'm easy to convince with facts.

Um, no you're not. You ignore facts that disagree with yours.
>
> Just "saying" you measured warp isn't going to work since I've heard people
> say that for decades and not one of them ever knew that the temperatures
> required would turn a braking system into mush.

Then you do not understand what goes on in braking systems in the real
world. The rotors I have seen and measured did not warp because I gave
them a *dark look*.
>
> Provide me even a _single_ reliable reference that says what you say, which
> is that people "think" rotors don't warp and yet they do.
> *Find just one*

A saw with my own eyes and measured with my own hands numerous warped
rotors.
>
> Without even a _single_ reliable reference backing up your claim, it's you
> who is being disingenuous. Not me.
>
> Note: I am well aware you can find a billion bullshit web pages selling new
> rotors that will "claim" the rotors warped so find a _reliable_ cite, like
> I did, from _experts_ who aren't selling anything but just telling the
> facts.
>
> Remember, a rotor will crack before it will warp.

Um, not always. I have seen plenty of rotors that were warped with no
signs of cracking. I have also seen the converse, cracked rotors with no
signs of warpage. It's a *different effect*.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 15/5/2022 4:17 am, Andy Burnelli wrote:
> Xeno wrote:
>
>>> On _that_ topic alone, have you ever seen a typical rotor "gouge" spec?
>>
>> Can't recall.
>
> Don't worry. I knew the answer before I asked it of you.
>
>> I just looked at the rotor gouge and, if *I* considered it too deep,
>> into the bin it went.
>
> I understand.
> I know all about what people do.
>> You have to realise that *any gouge* reduces the surface area for
>> braking so if it doesn't machine out, it will take ages for the pads
>> to fully bed, if at all, and will lead to unbalanced braking if the
>> gouges on each side of the car aren't balanced.
>
> It's a basic question I ask of everyone who claims to measure rotors.
> They never even _know_ what the gouge spec is.
>
>>> I have.
>>> That spec is often hard to find, but when found, it's shocking (to me).
>>> The first is that the spec allows _huge_ gouges (imho).
>>
>> I use my own judgement.
>
> Trust me, I know what you're going to say on rotors before you do.
>
> So don't worry.
> I expected it.
>
>>> And the second is I've never seen a rotor _that_ gouged.
>>
>> I have seen terribly gouged rotors - and I've binned them.
>
> I have only replaced my own rotors (and that of my family), where I
> haven't yet had to bin a rotor for anything other than for it being too
> thin.
>
> BTW, you got the reason rotor thickness matters wrong too, but that's OK.
> Everyone gets that wrong too, so I won't hold it against you.
>
>>> No big deal. I'd junk any rotor that doesn't meet spec w/o a second
>>> thought
>>> since a rotor is a safety item that costs only about $15 to $35 per
>>> wheel.
>>
>> Pre-cisely!
>
> As I said, there is only one "proper" way to decide if a rotor needs to
> be replaced, and it's _not_ what Steve said (he said every pad
> replacement or every other pad - but that's just bullshit from people
> who talk bullshit).
>
> Rest assured I know a _lot_ of morons out there say exactly what Steve
> does but when you ask them the kinds of questions I've been asking you,
> they fail the test instantly.
>
>>> My question to you are the two above:
>>> a. Have you seen how (seemingly) huge a gouge has to be to fail spec?
>>
>> Again, I use my own judgement.
>
> I know. I knew that before I asked you.
> Next time you work on rotors, ask the manufacturer for the spec.
>
> My prediction is you'll be shocked at how huge a gouge has to be to fail.

The only spec, ultimately, that matters is the minimum thickness spec.
If the rotor won't clean before minimum thickness is reached, any gouge
spec becomes irrelevant. I'm not going to put a machined rotor back on a
customer's car if *gouges* can still be seen on it - regardless of what
any gouge spec says.
>
>>> b. How often have _you_ seen a rotor gouged enough to fail that spec?
>>
>> I have had heaps of rotors, and drums, fail my judgemental spec.
>
> If they meet specs, I generally re-use them (unless they're for someone
> else, and then, in that case, I often replace good rotors anyway, since
> I don't know what kind of maintenance they will do in the future).

*I rest my case*! My brake work has always been for *customers* and, as
such, I place a high standard on it. You want to reuse a rotor I deem
too gouged, you will find yourself doing the job for *I* won't touch it.
It's called *responsibility*, perhaps you've heard of the concept?
>
> Luckily, in the USA, as long as you meet or exceed OEM specs, we can't
> get an unsafe rotor, and we can't get an unsafe brake pad, nor an unsafe
> tire (notwithstanding one-of-a-kind fuckups like the Firestone one of
> course).
>
> But we can pay $50 per axle for crappy pads (e.g., EE) and we can pay
> $50 each for rotors (there are no crappy rotors), and we can pay $200
> for crappy tires (there are no unsafe tires), etc., if we don't know
> what we're doing (or, more to the point, if we think "we get what we pay
> for").
>
> In my humble experience, typical sedan & SUV rotors are something like
> $15 to $35 each, and typical FF or GG or even HH pads are about the same
> per axle, and V-rated appropriate load index tires are almost always
> somewhere around $75 to $100 each (depending of course on the size &
> type of tire).

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 5/16/2022 12:20 AM, Andy Burnelli wrote:
> AMuzi wrote:
>
>> further to my recent comments:
>> http://forums.pelicanparts.com/uploads20/REDHOTBR+7001334174918.jpg
>>
>
> Destructive testing has its place in terms of gathering
> scientific data.
>
> That situation was artificially created on a special "test
> jig for brakes"
> by Porsche as shown here
> <https://seinesystems.com/BrakeFade.htm>
> "Yellow color indicates rotor surface temperature of
> approximately 2000ºF.
> Fresh, heavy duty brake fluid boils at around 450-550ºF."
> Copyright 1997 Porsche Cars North America, Inc."
>
> Nobody is saying you can't run an engine with the brakes
> held for what constitutes dozens of miles continuously at
> 150mph & the rotors get red.
> <https://www.pinterest.com/pin/glowing-exhaust-page-2-pelican-parts-technical-bbs--419819996486878798/>
>
>
> Bugati did it here, for example at continuous speeds over
> 150 mph with the
> calipers locked for minutes on end while measuring
> temperature & speed.
> <https://youtu.be/QIc-9UuLSmg?t=161>
>
> I _love_ destructive testing. In fact, purposefully
> destructive testing is a wonderful thing to watch.
>
> "We doctored the rotor to get it red hot to subject it to
> rapid cooling."
> https://youtu.be/B6UM4P1c8mA?t=789
> Sparks. Fire. Multiple dousing with water. Cracks galore.
> Even the brake pads were melted and misshapen after that
> torture test.
> Just like the reliable references I provided said would happen.
>
> See also:
> <https://rob928.home.xs4all.nl/928info/_home.htm>
> <http://forums.pelicanparts.com/porsche-911-technical-forum/639508-glowing-exhaust-2.html>
>
> <https://www.r3vlimited.com/board/forum/general-forums/general-discussion/9945-red-hot-brakes#post568873>
>

Yes but beyond rotor temperature note the caliper and other
components are _not_ glowing hot.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

In message <jee96bFmsjhU1@mid.individual.net> Xeno <xenolith@optusnet.com.au> wrote:
> I gave you the one I value most, my direct experience.

No matter who you are, "my own experiences" is not a reference, much
less a reliable one.

A reference is something published and accepted by others, preferably
through an editorial process that includes exports in the field. It is
not some guy saying "this is my experience" even though that might be
useful in some cases.

About the only exception to this is pure math where you can demonstrate
a proof, and even there when you apply those numbers to real-world
problems you may still be doing it wrong.

Here's an example that might relate to you and help you understand.

In the US, there was a problem with aluminum electrical wiring in homes,
and the use of aluminum wiring in new construction is banned because it
is too easy for it to cause house fires.

Now, some people will decide that "ZOMG! This house has electrical
wiring that is aluminum, I have to rewrite the house before it
explodes!"

An experienced electrician will tell you that, yes, you should probably
rewire because it isn't safe.

The same electrician will go home to his/her house with aluminum wiring
and will not lose a second of sleep.

Why? Because the electrician knows from experience that aluminum wiring
is only an issue if incompetent nincompoops (like home owners) fuck with
it and don't know what they are doing.

But no electrician is going to cite their personal experience with
aluminum wiring, or point out that there are plenty of ~70 year old
houses with aluminum wiring still out there not catching on fire,
because personal knowledge and experience is not a reference.

If you want to argue about something, you need to be able to provide
actual references.

All of that said, in this case you are wallowing in mud with a
shit-covered pig on his home turf, all that will happen here is that you
are going to smell like a pig covered in shit and the pig you are arguing
with is going to be very happy. VERY happy.

Please, every time you're going to reply to him imagine that little
chubby he gets and think again. Do you really want to be responsible for
the only sexual stimulation that obese naked troglodyte gets in his
life? Please, think of that image first.

--
'In the Fyres of Struggle let us bake New Men, who Will Notte heed
the old Lies.'

On 17/5/2022 12:19 am, Lewis wrote:
> In message <jee96bFmsjhU1@mid.individual.net> Xeno <xenolith@optusnet.com.au> wrote:
>> I gave you the one I value most, my direct experience.
>
> No matter who you are, "my own experiences" is not a reference, much
> less a reliable one.

Indeed but Arlen says warped rotors don't exist, I say they do because I
have seen them, I have measured them, I have machined them. There are
video references showing *warped rotors* so they do exist.
>
> A reference is something published and accepted by others, preferably
> through an editorial process that includes exports in the field. It is
> not some guy saying "this is my experience" even though that might be
> useful in some cases.
>
> About the only exception to this is pure math where you can demonstrate
> a proof, and even there when you apply those numbers to real-world
> problems you may still be doing it wrong.

The maths involved is above my pay grade. ;-)
>
> Here's an example that might relate to you and help you understand.
>
> In the US, there was a problem with aluminum electrical wiring in homes,
> and the use of aluminum wiring in new construction is banned because it
> is too easy for it to cause house fires.
>
> Now, some people will decide that "ZOMG! This house has electrical
> wiring that is aluminum, I have to rewrite the house before it
> explodes!"
>
> An experienced electrician will tell you that, yes, you should probably
> rewire because it isn't safe.
>
> The same electrician will go home to his/her house with aluminum wiring
> and will not lose a second of sleep.
>
> Why? Because the electrician knows from experience that aluminum wiring
> is only an issue if incompetent nincompoops (like home owners) fuck with
> it and don't know what they are doing.

I have seen the same incompetent nincompoops dick with vehicle wiring
that they simply do not understand. Had a friend show me a heated and
*melted* headlight socket and said it was caused by a *short*. Didn't
understand enough about electricity to see that a resistance causes a
voltage drop which, in turn, generates heat. What he was looking at was
the after effects of a bad connection in a relatively high current
environment.
>
> But no electrician is going to cite their personal experience with
> aluminum wiring, or point out that there are plenty of ~70 year old
> houses with aluminum wiring still out there not catching on fire,
> because personal knowledge and experience is not a reference.

No experience with aluminium wiring because, as far as I am aware, it
isn't legal in this country. I can imagine scenarios where incompetent
nincompoops can right royally screw something like that. I have a name
for people like that - Crayfish - the meat is in the tail, the shit in
the head!
>
> If you want to argue about something, you need to be able to provide
> actual references.
>
> All of that said, in this case you are wallowing in mud with a
> shit-covered pig on his home turf, all that will happen here is that you
> are going to smell like a pig covered in shit and the pig you are arguing
> with is going to be very happy. VERY happy.
>
> Please, every time you're going to reply to him imagine that little
> chubby he gets and think again. Do you really want to be responsible for
> the only sexual stimulation that obese naked troglodyte gets in his
> life? Please, think of that image first.
>
It's a stark image you paint there! ;-)

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

Xeno wrote:

>> If they meet specs, I generally re-use them (unless they're for someone
>> else, and then, in that case, I often replace good rotors anyway, since
>> I don't know what kind of maintenance they will do in the future).
>
> *I rest my case*! My brake work has always been for *customers* and, as
> such, I place a high standard on it. You want to reuse a rotor I deem
> too gouged, you will find yourself doing the job for *I* won't touch it.
> It's called *responsibility*, perhaps you've heard of the concept?

Why did you concoct that purely imaginary fanciful strawman above Xeno?

I wonder if you own the cognitive skills to realize you just proved my case
and, at the same time, you proved that you can't comprehend basic facts?

Basic facts that you can't seem to comprehend:
a. I said I junk a rotor (of my own) that doesn't meet spec.
b. I said I even sometimes junk a rotor (for others) that meets spec.
c. Better yet, I've said many times I've never seen gouges on those rotors.
d. And better still, I call the manufacturer to _get_ the rotor specs.

From those four stated facts, you comprehended _zero_ of them.
Why did you miss _every_ fact?

I don't know why.
I suspect you're desperate.

Like Alan Baker, you're desperate to _ignore_ all facts.
You're desperate to try to find any way around all those facts.

You're so desperate, you won't even _read_ what the experts say.

In your desperation to ignore facts, you actually _concocted_ an imaginary
situation where I allowed gouged rotors to remain on the vehicle.

Let me ask you a simple logical sensible question please, Xeno.
Is it _possible_ to have an _adult_ conversation with someone like you?

My observations (based on the facts), Xeno:
1. You strongly believe in what experts say is a common myth, and,
2. You completely and totally ignore all facts from those experts, and,
3. You believe only in a 20-second video from a 12 year old kid, and,
4. in the end, you are desperate to concoct a strawman that was never said.

Why did you concoct that purely imaginary fanciful strawman above Xeno?
--
I welcome someone (anyone) who can bring actual expert's facs to the fore.

Xeno wrote:

>> But the facts remain that you need an astoundingly huge temperature,
>> whether applied locally or not, to force a rotor to deform like that.
>
> Rotors never heat *uniformly*. In fact, it is the outer periphery that
> will heat the most and it is the outer periphery that will begin to
> deform first.

I'm willing to listen to and read and watch "good science"; but I must
first let you know that I'm allergic to people trying to bullshit me.

I'm all about good science, where I appreciated that Vic Smith brought up
that engineering test article which shows there "can" be deformation; but
unfortunately, that deformation came after ten hours at a thousand degrees.

A car brake system would be mush after ten hours at a thousand degrees.

If you can find even a _single_ reliable expert in the field who can back
up your belief system, post the reference and I'll read it. But please stop
it with the 20 second videos from a 12 year old.

If you can't find even a _single_ reliable reference from experts in the
field, then that alone should tell you what you won't believe from me about
your strongly held belief system.

I recognize that people hold onto belief systems that have absolutely no
basis (otherwise, religion wouldn't exist, for example), but if you're
going to try to discuss rotor warp, and yet, if you're going to ignore a
dozen reliable cites, then at least provide a reliable cite of your own.

What Amuzi said is certainly an interesting hypothesis... what we need to
explore it further is good solid references that back up his hypothesis.

Does _anyone_ out there have a _single_ reliable cite to back up the
hypothesis that Amuzi proposed to explain how rotors can commonly "warp"
when the temperature that is required would make the rest of the braking
system boil & seals would disintegrate before rotors could get to even one
quarter of the required temperature.

In summary, if you don't believe the dozen references I provided, then
you're not going to believe a thousand more from me; so it's up to _you_ to
provide a reliable reference.
--
And no, a 20 second video from a 12 year old isn't reliable science.

Lewis wrote:

> personal knowledge and experience is not a reference.

Lewis is correct, in my opinion, which I can back up with reliable cites:
*How Anecdotal Evidence Can Undermine Scientific Results*
<https://www.scientificamerican.com/article/how-anecdotal-evidence-can-undermine-scientific-results/>

*Anecdotes are not science*
<https://seths.blog/2021/06/anecdotes-are-not-science/>

*Anecdotes are not evidence*
<https://www.runresearchjunkie.com/anecdotes-are-not-evidence/>

Being a well educated reasonably intelligent person, I agree with anyone,
when he makes a cogent argument based on logic, sense, reason, and facts.

I completely agree with Lewis that "experience" has its place, but any one
person's experience doesn't trump the experts when the situation is thus:

1. The dozen expert's cites _all_ said it was a commonly held myth.
2. Those who believe in the common myth produced _zero_ expert's cites.
3. Worse, they produced easily refuted bullshit (their video & photo).

Like a sleazy politician, those who proffered those photos and their own
testimonials at the same time that they _refused_ to read the cites show
very clearly that this isn't about facts to them; it's about dogma.

Rest assured anyone with adult cognition would instantly notice
A. Vic Smith
B. Xeno
C. Amuzi

A. *Vic Smith*
He produced a paper of perfectly good science, which performed destructive
testing on already warped rotors, where those rotors were purposefully
deformed in a thousand degree oven for ten hours. While this was helpful
to them (they're discussing the value of heat treatments at the factory),
it's not _directly_ applicable in its entirety to this discussion.

B. *Xeno*
He strongly argued that his experience trumps _all_ scientific fact.

Worse, he constructed imaginary strawmen to attack since he had
no logical defense to the dozen experts' cites which were provided.

Even worse, he said he doesn't need any expert's opinion,
simply because he holds his own strongly held opinions based
solely on his experience and on his experience alone.

C. *Amuzi*
He seems to have understood the temperature dilemma, where he
hypothesized that perhaps the required temperature was achieved
only locally, which is an interesting hypothesis that the
experts covered in terms of the effect would be cracking.

But what destroyed his good faith is he tried to pull a
sleazy political trick by showing a doctored photo from
a destructive test jig (much as Vic Smith did but Vic
actually provided the reference but Amuzi didn't realize
I knew _instantly_ where that doctored photo came from).

In the end, people are _desperate_ to defend the myth.
What's interesting is that it's exactly what the iKooks do.

No amount of logic, sense, or reason will ever sway them
from what they intuit - facts to the contrary be damned.
--
There isn't an argument yet proposed I haven't seen in the
past as this myth of the warped rotors is commonly held.