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Date: 23 Mar 2007 19:44:36
From: Robert Harmon
Subject: looking for alternatives to tube-type pressure gauges
There must be better alternatives to the Bourdon Tube pressure sensors used
in commercial espresso machines. These things have so many external factors
affecting their accuracy that cost must be the only reason they're still
being used. If I remember correctly, a professor once said the technology
was over a hundred years old & that was *way* back when I was in college
(sometime before John The Baptist?).

There are alternatives; piston & oil filled types come to mind. But there
must be better ways to measure something as simple as water/steam pressure.

Suggestions or experiences?
--
Robert (No pressure, man!) Harmon
http://tinyurl.com/2tnv87






 
Date: 23 Mar 2007 19:21:59
From: Andy Schecter
Subject: Re: looking for alternatives to tube-type pressure gauges
Robert Harmon wrote:
> There must be better alternatives to the Bourdon Tube pressure sensors used
> in commercial espresso machines. These things have so many external factors
> affecting their accuracy that cost must be the only reason they're still
> being used. If I remember correctly, a professor once said the technology
> was over a hundred years old & that was *way* back when I was in college
> (sometime before John The Baptist?).
>
> There are alternatives; piston & oil filled types come to mind. But there
> must be better ways to measure something as simple as water/steam pressure.
>
> Suggestions or experiences?

I don't understand your desire for an alternative. If an inexpensive gauge is
accurate to within one or two percent at midscale, why pay ten times as much
for something that won't improve your coffee one bit?

--


-Andy S.

http://www.flickr.com/photos/andy_s/sets/


  
Date: 23 Mar 2007 19:24:47
From: Craig Andrews
Subject: Re: looking for alternatives to tube-type pressure gauges

"Andy Schecter" <schecter@remove.me.rochester.rr.com > wrote in message
news:460460f0$0$17201$4c368faf@roadrunner.com...
> Robert Harmon wrote:
>> There must be better alternatives to the Bourdon Tube pressure
>> sensors used in commercial espresso machines. These things have so
>> many external factors affecting their accuracy that cost must be the
>> only reason they're still being used. If I remember correctly, a
>> professor once said the technology was over a hundred years old &
>> that was *way* back when I was in college (sometime before John The
>> Baptist?).
>>
>> There are alternatives; piston & oil filled types come to mind. But
>> there must be better ways to measure something as simple as
>> water/steam pressure.
>>
>> Suggestions or experiences?
>
> I don't understand your desire for an alternative. If an inexpensive
> gauge is accurate to within one or two percent at midscale, why pay
> ten times as much for something that won't improve your coffee one
> bit?
>
> --
>

Yah got that right Bucko, as I think rob & I would say!
Craig.



 
Date: 23 Mar 2007 13:49:14
From: DavidMLewis
Subject: Re: looking for alternatives to tube-type pressure gauges
On 23, 12:44 pm, "Robert Harmon" <r_h_har...@Zhotmail.com > wrote:
> There must be better alternatives to the Bourdon Tube pressure sensors used
> in commercial espresso machines. These things have so many external factors
> affecting their accuracy that cost must be the only reason they're still
> being used. If I remember correctly, a professor once said the technology
> was over a hundred years old & that was *way* back when I was in college
> (sometime before John The Baptist?).
>
> Suggestions or experiences?

Ping Greg Scace. He's in the process of adding just such an item to
the latest version of the eponymous device.

Best,
David



  
Date: 23 Mar 2007 16:55:56
From: Craig Andrews
Subject: Re: looking for alternatives to tube-type pressure gauges

"DavidMLewis" <DavidMLewis@mac.com > wrote in message
news:1174682954.695422.59800@y66g2000hsf.googlegroups.com...
> On 23, 12:44 pm, "Robert Harmon" <r_h_har...@Zhotmail.com> wrote:
>> There must be better alternatives to the Bourdon Tube pressure
>> sensors used
>> in commercial espresso machines. These things have so many external
>> factors
>> affecting their accuracy that cost must be the only reason they're
>> still
>> being used. If I remember correctly, a professor once said the
>> technology
>> was over a hundred years old & that was *way* back when I was in
>> college
>> (sometime before John The Baptist?).
>>
>> Suggestions or experiences?
>
> Ping Greg Scace. He's in the process of adding just such an item to
> the latest version of the eponymous device.
>
> Best,
> David
>

Excellent!, cutting bleeding edge stuff!!
{;-D
Craig.



 
Date: 23 Mar 2007 15:34:45
From: seastl
Subject: Re: looking for alternatives to tube-type pressure gauges
On Fri, 23 2007 19:44:36 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>There must be better alternatives to the Bourdon Tube pressure sensors used
>in commercial espresso machines. These things have so many external factors
>affecting their accuracy that cost must be the only reason they're still
>being used. If I remember correctly, a professor once said the technology
>was over a hundred years old & that was *way* back when I was in college
>(sometime before John The Baptist?).
>
>There are alternatives; piston & oil filled types come to mind. But there
>must be better ways to measure something as simple as water/steam pressure.
>
>Suggestions or experiences?

A pressure transducer type? Here's an expensive example - it's +/- .05%
FS, and temp-compensated:

http://www.omega.com/ppt/pptsc.asp?ref=DPG4000

Brew pressure to one ten-thousandth of a pound? Cheaper alternatives
abound though.

Brad


  
Date: 23 Mar 2007 20:44:21
From: Robert Harmon
Subject: Re: looking for alternatives to tube-type pressure gauges
seastl <<reserved@later.date.com >> wrote in
news:1308ef7biutal20@news.supernews.com:

> On Fri, 23 2007 19:44:36 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
>>There must be better alternatives to the Bourdon Tube pressure sensors
>>used in commercial espresso machines. These things have so many
>>external factors affecting their accuracy that cost must be the only
>>reason they're still being used. If I remember correctly, a professor
>>once said the technology was over a hundred years old & that was *way*
>>back when I was in college (sometime before John The Baptist?).
>>
>>There are alternatives; piston & oil filled types come to mind. But
>>there must be better ways to measure something as simple as
>>water/steam pressure.
>>
>>Suggestions or experiences?
>
> A pressure transducer type? Here's an expensive example - it's +/-
> .05% FS, and temp-compensated:
>
> http://www.omega.com/ppt/pptsc.asp?ref=DPG4000
>
> Brew pressure to one ten-thousandth of a pound? Cheaper alternatives
> abound though.
>
> Brad
>
As a solution it might be a *bit* over the top, wouldn't you say?

I've looked at similar gauges (most were a bit cheaper), but it appears
these are still using old technology & then converting it to digital. The
solution probably needs to be in a sensor not the gauge itself.

Robert (duck & cover) Harmon
--
http://tinyurl.com/pou2y
http://tinyurl.com/fkd6r
Remove "Z" to reply via email.


   
Date: 23 Mar 2007 17:31:31
From: seastl
Subject: Re: looking for alternatives to tube-type pressure gauges
On Fri, 23 2007 20:44:21 GMT, Robert Harmon <r_h_harmon@Zhotmail.com >
wrote:

>seastl <<reserved@later.date.com>> wrote in
>news:1308ef7biutal20@news.supernews.com:
>
>> On Fri, 23 2007 19:44:36 GMT, "Robert Harmon"
>> <r_h_harmon@Zhotmail.com> wrote:
>>
>>>There must be better alternatives to the Bourdon Tube pressure sensors
>>>used in commercial espresso machines. These things have so many
>>>external factors affecting their accuracy that cost must be the only
>>>reason they're still being used. If I remember correctly, a professor
>>>once said the technology was over a hundred years old & that was *way*
>>>back when I was in college (sometime before John The Baptist?).
>>>
>>>There are alternatives; piston & oil filled types come to mind. But
>>>there must be better ways to measure something as simple as
>>>water/steam pressure.
>>>
>>>Suggestions or experiences?
>>
>> A pressure transducer type? Here's an expensive example - it's +/-
>> .05% FS, and temp-compensated:
>>
>> http://www.omega.com/ppt/pptsc.asp?ref=DPG4000
>>
>> Brew pressure to one ten-thousandth of a pound? Cheaper alternatives
>> abound though.
>>
>> Brad
>>
>As a solution it might be a *bit* over the top, wouldn't you say?
>
>I've looked at similar gauges (most were a bit cheaper), but it appears
>these are still using old technology & then converting it to digital. The
>solution probably needs to be in a sensor not the gauge itself.

Yeah, I guess that was a bit extreme! Transducer is probably the
technology to use. What would be nice is a very accurate transducer that
ran a 2" gauge with old-fashioned face (like an old-style LM gauge). You'd
lose some accuracy just in the mechanism though.

Brad


  
Date: 23 Mar 2007 16:41:48
From: Craig Andrews
Subject: Re: looking for alternatives to tube-type pressure gauges

"seastl >" <<reserved@later.date.com> wrote in message
news:1308ef7biutal20@news.supernews.com...
> On Fri, 23 2007 19:44:36 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
>>There must be better alternatives to the Bourdon Tube pressure sensors
>>used
>>in commercial espresso machines. These things have so many external
>>factors
>>affecting their accuracy that cost must be the only reason they're
>>still
>>being used. If I remember correctly, a professor once said the
>>technology
>>was over a hundred years old & that was *way* back when I was in
>>college
>>(sometime before John The Baptist?).
>>
>>There are alternatives; piston & oil filled types come to mind. But
>>there
>>must be better ways to measure something as simple as water/steam
>>pressure.
>>
>>Suggestions or experiences?
>
> A pressure transducer type? Here's an expensive example - it's +/-
> .05%
> FS, and temp-compensated:
>
> http://www.omega.com/ppt/pptsc.asp?ref=DPG4000
>
> Brew pressure to one ten-thousandth of a pound? Cheaper alternatives
> abound though.
>
> Brad

A few days ago I was looking at a remote digital pressure sensing unit
that transmits 4 tire pressure values simultaniously/independantly in
real time to the display inside the truck/vehicle & was only $129.99
Canadian!
Craig.



   
Date: 23 Mar 2007 16:47:58
From: Craig Andrews
Subject: Re: looking for alternatives to tube-type pressure gauges

"Craig Andrews" <alt.coffee@deletethis.rogers.com > wrote in message
news:56isc9F296kjvU1@mid.individual.net...
>
> "seastl >" <<reserved@later.date.com> wrote in message
> news:1308ef7biutal20@news.supernews.com...
>> On Fri, 23 2007 19:44:36 GMT, "Robert Harmon"
>> <r_h_harmon@Zhotmail.com> wrote:
>>
>>>There must be better alternatives to the Bourdon Tube pressure
>>>sensors used
>>>in commercial espresso machines. These things have so many external
>>>factors
>>>affecting their accuracy that cost must be the only reason they're
>>>still
>>>being used. If I remember correctly, a professor once said the
>>>technology
>>>was over a hundred years old & that was *way* back when I was in
>>>college
>>>(sometime before John The Baptist?).
>>>
>>>There are alternatives; piston & oil filled types come to mind. But
>>>there
>>>must be better ways to measure something as simple as water/steam
>>>pressure.
>>>
>>>Suggestions or experiences?
>>
>> A pressure transducer type? Here's an expensive example - it's +/-
>> .05%
>> FS, and temp-compensated:
>>
>> http://www.omega.com/ppt/pptsc.asp?ref=DPG4000
>>
>> Brew pressure to one ten-thousandth of a pound? Cheaper alternatives
>> abound though.
>>
>> Brad
>
> A few days ago I was looking at a remote digital pressure sensing unit
> that transmits 4 tire pressure values simultaniously/independantly in
> real time to the display inside the truck/vehicle & was only $129.99
> Canadian!
> Craig.

Sorry, 4 mini remote sensors mounted on the Schrader/valve stems., in
place of the valve caps! {:-D
Craig.



    
Date: 23 Mar 2007 17:26:56
From: seastl
Subject: Re: looking for alternatives to tube-type pressure gauges
On Fri, 23 2007 16:47:58 -0400, "Craig Andrews"
<alt.coffee@deletethis.rogers.com > wrote:

>
>"Craig Andrews" <alt.coffee@deletethis.rogers.com> wrote in message
>news:56isc9F296kjvU1@mid.individual.net...
>>
>> "seastl >" <<reserved@later.date.com> wrote in message
>> news:1308ef7biutal20@news.supernews.com...
>>> On Fri, 23 2007 19:44:36 GMT, "Robert Harmon"
>>> <r_h_harmon@Zhotmail.com> wrote:
>>>
>>>>There must be better alternatives to the Bourdon Tube pressure
>>>>sensors used
>>>>in commercial espresso machines. These things have so many external
>>>>factors
>>>>affecting their accuracy that cost must be the only reason they're
>>>>still
>>>>being used. If I remember correctly, a professor once said the
>>>>technology
>>>>was over a hundred years old & that was *way* back when I was in
>>>>college
>>>>(sometime before John The Baptist?).
>>>>
>>>>There are alternatives; piston & oil filled types come to mind. But
>>>>there
>>>>must be better ways to measure something as simple as water/steam
>>>>pressure.
>>>>
>>>>Suggestions or experiences?
>>>
>>> A pressure transducer type? Here's an expensive example - it's +/-
>>> .05%
>>> FS, and temp-compensated:
>>>
>>> http://www.omega.com/ppt/pptsc.asp?ref=DPG4000
>>>
>>> Brew pressure to one ten-thousandth of a pound? Cheaper alternatives
>>> abound though.
>>>
>>> Brad
>>
>> A few days ago I was looking at a remote digital pressure sensing unit
>> that transmits 4 tire pressure values simultaniously/independantly in
>> real time to the display inside the truck/vehicle & was only $129.99
>> Canadian!
>> Craig.
>
>Sorry, 4 mini remote sensors mounted on the Schrader/valve stems., in
>place of the valve caps! {:-D
>Craig.

That's a good deal, sounds like. My car has that, and it's nice - but kind
of a pain. The sensors need to be cleaned about each 3 years or their
transmitting ability gets week. The four sensors for my system cost almost
as much as your system quote is, as I had to buy an extra set for winter
tires & rims. It makes you appreciate how critical proper tire pressure
is, and how much it varies with the temperature. I was thinking about
going to dry nitrogen like some stations in europe offer. I've heard
claims that it can exetnd your tire life by around 25%. So many ideas, so
little time...

Brad


     
Date: 23 Mar 2007 15:52:24
From: Roger Shoaf
Subject: Re: looking for alternatives to tube-type pressure gauges

"seastl >" <<reserved@later.date.com> wrote in message
news:1308l1igkuqlk06@news.supernews.com...
I was thinking about
> going to dry nitrogen like some stations in europe offer. I've heard
> claims that it can exetnd your tire life by around 25%. So many ideas, so
> little time...
>
> Brad

According to Cecil Adams (the Straight Dope) you need not waste the effort.
http://www.straightdope.com/columns/070216.html

--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.




      
Date: 24 Mar 2007 02:57:16
From: D. Ross
Subject: Re: looking for alternatives to tube-type pressure gauges


       
Date: 23 Mar 2007 22:23:24
From: seastl
Subject: Re: looking for alternatives to tube-type pressure gauges
On Sat, 24 2007 02:57:16 GMT, ross@math.hawaii.NOSPAM.edu (D. Ross)
wrote:

>


      
Date: 23 Mar 2007 18:05:59
From: seastl
Subject: Re: looking for alternatives to tube-type pressure gauges
On Fri, 23 2007 15:52:24 -0700, "Roger Shoaf" <shoaf@nospamsyix.com >
wrote:

>
>"seastl >" <<reserved@later.date.com> wrote in message
>news:1308l1igkuqlk06@news.supernews.com...
> I was thinking about
>> going to dry nitrogen like some stations in europe offer. I've heard
>> claims that it can exetnd your tire life by around 25%. So many ideas, so
>> little time...
>>
>> Brad
>
>According to Cecil Adams (the Straight Dope) you need not waste the effort.
>http://www.straightdope.com/columns/070216.html

I'd have to agree with the bulk of that. If you had a truck fleet or
something, maybe. Or, if it was widely available (so you wouldn't have to
buy your own N2 setup). I do disagree with the dismissal of the effect of
moisture on alloy wheels. Aluminum alloy wheels can be very adversely
affected by moisture in the air inside and I've seen it first hand more
than once. Not sure what alloy was used in those cases, however.

Brad


 
Date: 23 Mar 2007 16:07:23
From: Craig Andrews
Subject: Re: looking for alternatives to tube-type pressure gauges

"Robert Harmon" <r_h_harmon@Zhotmail.com > wrote in message
news:E6WMh.17027$Jl.5390@newsread3.news.pas.earthlink.net...
> There must be better alternatives to the Bourdon Tube pressure sensors
> used in commercial espresso machines. These things have so many
> external factors affecting their accuracy that cost must be the only
> reason they're still being used. If I remember correctly, a professor
> once said the technology was over a hundred years old & that was *way*
> back when I was in college (sometime before John The Baptist?).
>
> There are alternatives; piston & oil filled types come to mind. But
> there must be better ways to measure something as simple as
> water/steam pressure.
>
> Suggestions or experiences?
> --
> Robert (No pressure, man!) Harmon
> http://tinyurl.com/2tnv87
>

Hi Robert, Maybe you saw the pics of my wet glycerin filled pressure
measuring portafilter setup I made & posted on the Coffeegeek forums.
This gauge is so efficient that I of course didn't even need a "snubber"
valve in line to the gauge.
http://www.coffeegeek.com/forums/espresso/machines/283783
Craig.



  
Date: 23 Mar 2007 20:22:38
From: Robert Harmon
Subject: Re: looking for alternatives to tube-type pressure gauges
Howdy Craig!
I did take a brief look, but I don't believe that's really what I'm after.
Is the gauge you're using a piston type or Bourdon Tube? I'm trying to find
at least a 20th Century (preferably late 20th C) solution. Somewhere there
has to be a sensor small and robust enough to be placed *in* the
boiler/group for the most accurate readings.
--
Robert (Gig 'em!) Harmon
http://tinyurl.com/2tnv87

"Craig Andrews" <alt.coffee@deletethis.rogers.com > wrote in message
news:56iqboF289vrsU1@mid.individual.net...
>
> "Robert Harmon" <r_h_harmon@Zhotmail.com> wrote in message
> news:E6WMh.17027$Jl.5390@newsread3.news.pas.earthlink.net...
>> There must be better alternatives to the Bourdon Tube pressure sensors
>> used in commercial espresso machines. These things have so many external
>> factors affecting their accuracy that cost must be the only reason
>> they're still being used. If I remember correctly, a professor once said
>> the technology was over a hundred years old & that was *way* back when I
>> was in college (sometime before John The Baptist?).
>>
>> There are alternatives; piston & oil filled types come to mind. But there
>> must be better ways to measure something as simple as water/steam
>> pressure.
>>
>> Suggestions or experiences?
>> --
>> Robert (No pressure, man!) Harmon
>> http://tinyurl.com/2tnv87
>>
>
> Hi Robert, Maybe you saw the pics of my wet glycerin filled pressure
> measuring portafilter setup I made & posted on the Coffeegeek forums. This
> gauge is so efficient that I of course didn't even need a "snubber" valve
> in line to the gauge.
> http://www.coffeegeek.com/forums/espresso/machines/283783
> Craig.




   
Date: 23 Mar 2007 16:25:30
From: Craig Andrews
Subject: Re: looking for alternatives to tube-type pressure gauges

"Robert Harmon" <r_h_harmon@Zhotmail.com > wrote in message
news:iGWMh.17043$Jl.11362@newsread3.news.pas.earthlink.net...
> Howdy Craig!
> I did take a brief look, but I don't believe that's really what I'm
> after. Is the gauge you're using a piston type or Bourdon Tube? I'm
> trying to find at least a 20th Century (preferably late 20th C)
> solution. Somewhere there has to be a sensor small and robust enough
> to be placed *in* the boiler/group for the most accurate readings.
> --
> Robert (Gig 'em!) Harmon
> http://tinyurl.com/2tnv87
>
> "Craig Andrews" <alt.coffee@deletethis.rogers.com> wrote in message
> news:56iqboF289vrsU1@mid.individual.net...
>>
>> "Robert Harmon" <r_h_harmon@Zhotmail.com> wrote in message
>> news:E6WMh.17027$Jl.5390@newsread3.news.pas.earthlink.net...
>>> There must be better alternatives to the Bourdon Tube pressure
>>> sensors used in commercial espresso machines. These things have so
>>> many external factors affecting their accuracy that cost must be the
>>> only reason they're still being used. If I remember correctly, a
>>> professor once said the technology was over a hundred years old &
>>> that was *way* back when I was in college (sometime before John The
>>> Baptist?).
>>>
>>> There are alternatives; piston & oil filled types come to mind. But
>>> there must be better ways to measure something as simple as
>>> water/steam pressure.
>>>
>>> Suggestions or experiences?
>>> --
>>> Robert (No pressure, man!) Harmon
>>> http://tinyurl.com/2tnv87
>>>
>>
>> Hi Robert, Maybe you saw the pics of my wet glycerin filled pressure
>> measuring portafilter setup I made & posted on the Coffeegeek forums.
>> This gauge is so efficient that I of course didn't even need a
>> "snubber" valve in line to the gauge.
>> http://www.coffeegeek.com/forums/espresso/machines/283783
>> Craig.
>
>

Digital pressure gauge then? {:-o
Craig.