"torque wrench" pump/compressor

[Emanuel Berg]

Just out of curiosity, is there a "torque
wrench" pump or compressor? I.e., you would
screw on the presta valve, set the gizmo to
e.g. 35psi, engage it, and instead of watching
the indicator, automagically at the right level
it would stop?

--
underground experts united
http://user.it.uu.se/~embe8573

[John B. Slocomb]

On Thu, 11 Oct 2018 08:54:38 +0200, Emanuel Berg <moa...@zoho.com>
wrote:

>Just out of curiosity, is there a "torque
>wrench" pump or compressor? I.e., you would
>screw on the presta valve, set the gizmo to
>e.g. 35psi, engage it, and instead of watching
>the indicator, automagically at the right level
>it would stop?

Most of the gas stations here use an air station that you can set for
your desired pressure and then just plug the hose onto the tire valve
- there is a little clamp to hold it there. When the tire is inflated
to the specified pressure the inflation stops and a bell rings.

Since they aren't manufactured here I had assumed that the rest of the
world had them too.
--

Cheers,

John B.

[AMuzi]

On 10/11/2018 1:54 AM, Emanuel Berg wrote:
> Just out of curiosity, is there a "torque
> wrench" pump or compressor? I.e., you would
> screw on the presta valve, set the gizmo to
> e.g. 35psi, engage it, and instead of watching
> the indicator, automagically at the right level
> it would stop?
>

WTF? Did I miss your joke?

http://www.pneumaticplus.com/air-regulator/

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

[Emanuel Berg]

AMuzi wrote:

>> Just out of curiosity, is there a "torque
>> wrench" pump or compressor? I.e., you would
>> screw on the presta valve, set the gizmo to
>> e.g. 35psi, engage it, and instead of
>> watching the indicator, automagically at the
>> right level it would stop?
>
> WTF? Did I miss your joke?

You don't have to be condescending. Instead be
happy you have so advanced technology at your
business! OK, so it is called an air regulator.

Don't forget to answer my still-unanswered
question on "65 PSI". Unless of course you only
want to answer my "joke" questions?

[Frank Krygowski]

My experience from 50+ years ago says not to rely on those things, although I suppose they may be different now.

Back then I blew a tire off the rim with one. I suspect the problem was the volume of each pumping stroke. In a large sized car tire, the volume surge with each big stroke would be absorbed and barely raise the pressure. In a low volume bike tire, it caused an explosion. That's my guess anyway.

I usually inflate using a manual floor pump with a gage. It's easy enough to stop pumping when the dial reads the desired temperature.

- Frank Krygowski

[Sir Ridesalot]

You need to understand that a lot of your "questions" sound suspiciously like trolling. Why not get a GOOD book on bicycle repair and learn the proper basic terminology and repair methods? Plus, with a good book you'd have the information at hand and not have to wait for replies from here.

BTW, as Frank stated, using a HIGH volume gas station air hose to fill a road-bicycle tire that has a comparatively very low volume will almost guarantee you'll blow your bicycle tire unless you're very quick at attaching and disengaging the hose.

Cheers

[Theodore Heise]

Don't you mean, when the dial reads the desired foot-pounds?

--
Ted Heise <the...@panix.com> West Lafayette, IN, USA

[Emanuel Berg]

Sir Ridesalot wrote:

> You need to understand that a lot of your
> "questions" sound suspiciously like trolling.
> Why not get a GOOD book on bicycle repair and
> learn the proper basic terminology and repair
> methods? Plus, with a good book you'd have
> the information at hand and not have to wait
> for replies from here.

I don't "need" or "have" to do anything. I do
exactly what I want. Like now for example, what
I want to do is add you to my KILL file.
But don't worry, there are tons of negativistic
lamers there already to keep you company.

[Theodore Heise]

Or lumens, if you want a multiple thread tie.

[Sir Ridesalot]

That you're trolling is confirmed!

Cheerio

[AMuzi]

funny. Pressure is mass/area usually. Except on RBT.

[Frank Krygowski]

Oh geez, my mistake!

But: Neither! I stop when it reads the desired PRESSURE!

Around here we use psi = pounds per square inch. Weirdly enough, my
pump's pressure gauge is also graduated in kg/cm^2. I would have used
that as a bad example in my courses, since kg is properly used to
measure mass, not force. And pressure is force per unit area.

(This indicates that the SI system gets misused as much as the U.S. or
Imperial system.)

--
- Frank Krygowski

[Andre Jute]

Nah, Franki-boy is just bragging, implying that he pumps so powerfully that the sudden increase in pressure in the tube raises the temperature of the air noticeably.

It does raise the question of how short, slight racing mechanics manage to push down the handle on road tubes inflated to awesome bars. I notice my SKS Rennkommprrrressorrrr is rated to 16 bars... of which I use two and a bit, never more than 3 bar

Andre Jute
When professional photographers had arms like gorillas

[Andre Jute]

Don't be such a pompous dickhead, Ridealot. Not everyone pretends to know everything, unlike you. Not everyone grew up on your street corner, and consequently value questions differently, and ask them differently too. In any event, when there are so many people willing to answer questions on any given subject, people with something else to fill their minds have no need to remember minor techie details when all one has to do is ask and be patient for about five minutes.

Andre Jute
Fed up with mindless hall monitors

[Frank Krygowski]

No, sorry, it's FORCE per unit area.

https://whatis.techtarget.com/definition/pressure

https://en.wikipedia.org/wiki/Pressure

Mass vs. weight vs. other forces is a big item of confusion for physics
and engineering students. Teachers work hard to correct the confusion.

--
- Frank Krygowski

[Frank Krygowski]

On 10/11/2018 6:10 PM, Andre Jute wrote:
> On Thursday, October 11, 2018 at 5:45:23 PM UTC+1, Sir Ridesalot wrote:
>> On Thursday, October 11, 2018 at 10:55:07 AM UTC-4, Emanuel Berg wrote:
>>> AMuzi wrote:
>>>
>>>>> Just out of curiosity, is there a "torque
>>>>> wrench" pump or compressor? I.e., you would
>>>>> screw on the presta valve, set the gizmo to
>>>>> e.g. 35psi, engage it, and instead of
>>>>> watching the indicator, automagically at the
>>>>> right level it would stop?
>>>>
>>>> WTF? Did I miss your joke?
>>>
>>> You don't have to be condescending. Instead be
>>> happy you have so advanced technology at your
>>> business! OK, so it is called an air regulator.
>>>
>>> Don't forget to answer my still-unanswered
>>> question on "65 PSI". Unless of course you only
>>> want to answer my "joke" questions?
>>>
>>> --
>>> underground experts united
>>> http://user.it.uu.se/~embe8573
>>
>> You need to understand that a lot of your "questions" sound suspiciously like trolling. Why not get a GOOD book on bicycle repair and learn the proper basic terminology and repair methods? Plus, with a good book you'd have the information at hand and not have to wait for replies from here.
>>
>> BTW, as Frank stated, using a HIGH volume gas station air hose to fill a road-bicycle tire that has a comparatively very low volume will almost guarantee you'll blow your bicycle tire unless you're very quick at attaching and disengaging the hose.
>>
>> Cheers
>
> Don't be such a pompous dickhead, Ridealot.

Right! That's Andre's job!

;-)


--
- Frank Krygowski

[John B. Slocomb]

On Thu, 11 Oct 2018 16:55:04 +0200, Emanuel Berg <moa...@zoho.com>
wrote:

The pressure rating on the tire, put there my the manufacturer, is
probably to try to ensure that someone doesn't try to pump the tire up
to an abnormally high pressure at which it might explode, thus
destroying the tire and giving the owner grounds to sue the maker.
"Hey! Your tire exploded and hurt my finger and now you got to give me
a while bunch of money."
--

Cheers,

John B.

[John B. Slocomb]

On Thu, 11 Oct 2018 19:55:06 +0200, Emanuel Berg <moa...@zoho.com>
wrote:

>Sir Ridesalot wrote:
>
>> You need to understand that a lot of your
>> "questions" sound suspiciously like trolling.
>> Why not get a GOOD book on bicycle repair and
>> learn the proper basic terminology and repair
>> methods? Plus, with a good book you'd have
>> the information at hand and not have to wait
>> for replies from here.
>
>I don't "need" or "have" to do anything. I do
>exactly what I want. Like now for example, what
>I want to do is add you to my KILL file.
>But don't worry, there are tons of negativistic
>lamers there already to keep you company.

Well, I've mentioned that you might research your questions before
asking them and Frank has even given you a list of books that might
enlighten you and now Sir has told you flat out that you do sound like
a troll.

Perhaps it is you that is at fault and not the growing group that
question your intent.
--

Cheers,

John B.

[AMuzi]

On 10/11/2018 6:03 PM, Frank Krygowski wrote:
> On 10/11/2018 3:30 PM, AMuzi wrote:
>> On 10/11/2018 12:53 PM, Theodore Heise wrote:
>>> On Thu, 11 Oct 2018 09:27:02 -0700 (PDT),

>>> Â Â Frank Krygowski <frkr...@gmail.com> wrote:
>>>> Â On Thursday, October 11, 2018 at 5:00:33 AM UTC-4,

>>>> John B. Slocomb wrote:
>>>>> On Thu, 11 Oct 2018 08:54:38 +0200, Emanuel Berg
>>>>> <moa...@zoho.com>
>>>>> wrote:
>>>>>
>>>>>> Just out of curiosity, is there a "torque wrench" pump or
>>>>>> compressor? I.e., you would screw on the presta valve,
>>>>>> set
>>>>>> the gizmo to e.g. 35psi, engage it, and instead of
>>>>>> watching
>>>>>> the indicator, automagically at the right level it would
>>>>>> stop?
>>>>>
>>>>> Most of the gas stations here use an air station that
>>>>> you can
>>>>> set for your desired pressure and then just plug the
>>>>> hose onto
>>>>> the tire valve
>>>>> - there is a little clamp to hold it there. When the
>>>>> tire is

>>>>> Â Â inflated to the specified pressure the inflation
>>>>> stops and a
>>>>> Â Â bell rings.

>>>>>
>>>>> Since they aren't manufactured here I had assumed that the
>>>>> rest of the world had them too.
>>>>

>>>> Â My experience from 50+ years ago says not to rely on
>>>> those
>>>> Â things, although I suppose they may be different now.
>>>>
>>>> Â Back then I blew a tire off the rim with one. I
>>>> suspect the
>>>> Â problem was the volume of each pumping stroke. In a
>>>> large sized
>>>> Â car tire, the volume surge with each big stroke would be
>>>> Â absorbed and barely raise the pressure. In a low
>>>> volume bike
>>>> Â tire, it caused an explosion. That's my guess anyway.
>>>>
>>>> Â I usually inflate using a manual floor pump with a
>>>> gage. It's
>>>> Â easy enough to stop pumping when the dial reads the
>>>> desired
>>>> Â temperature.

>>>
>>> Don't you mean, when the dial reads the desired foot-pounds?
>>>
>>
>> funny. Pressure is mass/area usually. Except on RBT.
>
> No, sorry, it's FORCE per unit area.
>
> https://whatis.techtarget.com/definition/pressure
>
> https://en.wikipedia.org/wiki/Pressure
>
> Mass vs. weight vs. other forces is a big item of confusion
> for physics and engineering students. Teachers work hard to
> correct the confusion.
>

Thank you.

As a 10th grade dropout, I understand the limits of an
autodidact education.

[jbeattie]

https://www.youtube.com/watch?v=bcYppAs6ZdI

-- Jay Beattie.

[John B. Slocomb]

When I was talking about the gas station automatic tie filler I wasn't
thinking about bicycles. In fact I can't remember ever filling a
bicycle tire at a gas station, just pump them up at home and ride :-)
But you are right, in a bicycle tire a small volume pumped in raises
the pressure substantially.
--

Cheers,

John B.

[John B. Slocomb]

On Thu, 11 Oct 2018 17:53:05 +0000 (UTC), Theodore Heise

More likely pounds per square inch, i.e. psi :-)
--

Cheers,

John B.

[John B. Slocomb]

But if you compress air it gets hotter so temperature should be taken
into consideration :-)

--

Cheers,

John B.

[John B. Slocomb]

But isn't "pound" a measurement of mass also :-?
--

Cheers,

John B.

[Radey Shouman]

When I was in school, years ago, we were quite strictly made to write
either lb_f (pound force) or lb_m (pound mass), and to include unit
conversions from one to the other using constants g (the nominal force
of graivty at the surface of the Earth) and g_c (a unit conversion factor).

The conversion is:

lb_f = lb_m * g / g_c

In English units g = 32.2 ft/s^2
g_c = 32.2 lb_m ft/s^2 lb_f

but if you didn't include the conversion, you failed.

[Frank Krygowski]

As I used to explain it to students: Properly speaking, a _force_ is a
push or a pull on an object. Properly speaking, _mass_ is a measure of
the amount of matter in an object. _Weight_ is a particular force, i.e.
the force of gravity on an object.

So in a U.S. grocery if you buy 2.2 pounds of cheese, you're buying the
amount of cheese upon which the earth's gravity exerts a force of two
pounds. It's a roundabout way of specifying the mass you want, but it
works as long as you're just talking cheese, etc.

In a European country, you'd specify you wanted a kilogram of cheese,
which is about 2.2 pounds worth. There, you're directly specifying the
amount of cheese you want.

That makes it sound like the Europeans are much smarter. But they turn
things around and sometimes measure forces in kilograms, or pressure in
kg/cm^2 etc.

Where it makes a difference is in calculations involving force, mass and
acceleration. Or other engineering calculations. If you don't clearly
understand whether you're dealing with force or with mass, you get
answers that are very, very wrong.

>
> When I was in school, years ago, we were quite strictly made to write
> either lb_f (pound force) or lb_m (pound mass), and to include unit
> conversions from one to the other using constants g (the nominal force
> of graivty at the surface of the Earth) and g_c (a unit conversion factor).
>
> The conversion is:
>
> lb_f = lb_m * g / g_c
>
> In English units g = 32.2 ft/s^2
> g_c = 32.2 lb_m ft/s^2 lb_f
>
> but if you didn't include the conversion, you failed.

Exactly! And students who ignored all that got answers that were wrong
by a factor of 32.2.

As I explained it, g_c ("Gee sub C") is just a conversion factor, in the
same way that (12 in / 1 ft) is a conversion factor. If a person
diligently showed units in their computations, it was obvious when it
was needed.

Most conversion factors have no names, and it always seemed weird to me
that they gave that conversion factor a name. Thousands of students got
endlessly confused between the acceleration of gravity
g, which is 32.2 ft/sec^2
and that conversion factor
g_c, which is 32.2 (lbm*ft)/(lbf*sec^2)

Diligent attention to units on ALL quantities straightens out that
confusion. At least, for most students.

And BTW, I found that engineers typically pay attention to units like
that. To my astonishment, some professors teaching basic physics did not.

--
- Frank Krygowski

[Emanuel Berg]

John B. Slocomb wrote:

> Well, I've mentioned that you might research
> your questions before asking them and Frank
> has even given you a list of books that might
> enlighten you and now Sir has told you flat
> out that you do sound like a troll.

You and a bunch of other guys, [insert your
name here] etc, can call me what you want, I'm
unaffected because every day tons of people
express gratefulness for everything I've done
in just a couple of years - with firewood,
carpentry, bikes, organization, gardening, home
improvement, bricklayer, and so on.

However people who ONLY make derogatory remarks
I'll killfile as it doesn't please me to
interact with this kind of person.

And this is my last remark on this topic :) So
if I don't respond to further replies, that
doesn't mean I agree, it means it don't find
this kind of discussion pleasant/productive :)

[Emanuel Berg]

AMuzi wrote:

> As a 10th grade dropout, I understand the
> limits of an autodidact education.

When was the last time you were wrong about
a bike issue?

I mean a principle matter, not grabbing the 9mm
combination spanner instead of the 10.

PS. Serious question! DS.

[John B. Slocomb]

Question. "Lb_m * g". how can you meaure 1 lb_m without gravety?
--

Cheers,

John B.

[John B. Slocomb]

On Fri, 12 Oct 2018 11:08:06 -0400, Frank Krygowski

I think I must have been out of school for too long. How is 1 kilogram
which equates to approximately2.20462262185 pounds a different
measurement than pounds? Aren't they both a measurement of the effect
of gravity on a certain amount of stuff?

Cheers,

John B.

[AMuzi]

In theory, smack it into something at a known velocity in
outer space. Nice weekend project.

Not that metric is any better, in that KPa does not equal Atm:
https://www.chemteam.info/GasLaw/PressureConversions.html

[Frank Krygowski]

Interestingly, they do that! Or rather, they do it in orbit or in free
fall*, which is effectively the same thing.

On the International Space Station, they attach the mass to a spring
system. The frequency of oscillation allows them to determine the mass.

Here you go: https://www.youtube.com/watch?v=8rt3udip7l4

(* Free fall or stable orbit isn't exactly "without gravity" because
gravity is acting on the object. But since the object is accelerating
freely in response to gravity, it's effectively the same as if the
gravitational force were zero.)

--
- Frank Krygowski

[Frank Krygowski]

First, don't trouble yourself. For ordinary everyday stuff it doesn't
matter.

But at its heart, mass is not the same as weight. For a simple example,
if you took a 1 kg mass to the moon its mass would still be 1 kg. But
its weight would be about 1/6 of what it was on earth. And in the ISS
the observed weight or effective weight of that object would be zero.

Again, if you're just (say) buying cheese on the surface of the earth
the difference doesn't matter. If you don't keep it straight in
calculations involving dynamics - as in "how much tension will be on
this connecting rod?" - you're apt to get answers that are off by a
factor of 32. Or in an SI system country, off by a factor of 9.8 or so.


--
- Frank Krygowski

[Radey Shouman]

Apply a known force and see how fast it accelerates.

--

[John B. Slocomb]

On Fri, 12 Oct 2018 22:16:00 -0400, Frank Krygowski

Ah, I understand. So what you are really talking about is an object
falling without any resistance of the air... cause there ain't none
and feathers fall as fast as lumps of lead :-)

--

Cheers,

John B.

[John B. Slocomb]

On Fri, 12 Oct 2018 22:21:58 -0400, Frank Krygowski

O.K. mass would be a factor in the acceleration of an object when a
force is applied to it.

--

Cheers,

John B.