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Date: 18 Mar 2007 22:52:00
From: seastl
Subject: A few Silvia questions

Hello Everyone,

Long-time lurker, first-time poster!

I am a recent purchaser and near-future modifier of a Silvia and I have a
few questions about the machine.

The silvia has a standpipe in the boiler where the brew water exits
enroute to the 3-way valve. The brew water is drawn from the boiler
approximately 1 inch away from the water inlet (at least that's how I
deduce from the illustrated parts listing). Why is this? Would the outlet
water temp not be more homgenous if the standpipe were somewhat lower? Has
anyone experimented with this? What are the possible ramifications of
lowering the inlet?

I found a passing mention (can't recall where) of someone either
contemplating or actually performing a preheat mod where the fresh water
was passed around the boiler a few times before entering it. I was
envisioning doing this with 1/4" copper tubing either induction-style or
direct contact (not sure which would be better, but would think
direct-contact would be). Does anyone have experience with this type of
mod?

Is there a chance that the above two mods could significantly reduce the
typical "stock" temp decline during a pull? I have only begun collecting
parts for a PID, but the first batch of beans that I have used with the
machine are very finicky, and the temp instability is frustrating. I'll
have some more MG beans by the end of next week, thankfully.

Any thoughts on these two temp issues would be much appreciated.

Brad




 
Date: 23 Mar 2007 09:30:51
From: hbuchtel
Subject: Re: A few Silvia questions
Hello Brad, I don't want to get too off subject, but why did you
choose a Sylvia for your project instead of one of the Gaggia domestic
models?

As far as I can tell the Gaggias have two advantages, the group is
mounted directly on the bottom of the boiler (not off-set like the
Sylvia) and the pump feed is from the bottom, actually through the
group (I think).

The boiler is quite a bit smaller and made of aluminium, but if you
are going to be pre-heating the incoming water that shouldn't be a big
deal.

Your thoughts?

Henry

On 19, 11:52 am, seastl <<reser...@later.date.com >> wrote:
> Hello Everyone,
>
> Long-time lurker, first-time poster!
>
> I am a recent purchaser and near-future modifier of a Silvia and I have a
> few questions about the machine.
>
> The silvia has a standpipe in the boiler where the brew water exits
> enroute to the 3-way valve. The brew water is drawn from the boiler
> approximately 1 inch away from the water inlet (at least that's how I
> deduce from the illustrated parts listing). Why is this? Would the outlet
> water temp not be more homgenous if the standpipe were somewhat lower? Has
> anyone experimented with this? What are the possible ramifications of
> lowering the inlet?
>
> I found a passing mention (can't recall where) of someone either
> contemplating or actually performing a preheat mod where the fresh water
> was passed around the boiler a few times before entering it. I was
> envisioning doing this with 1/4" copper tubing either induction-style or
> direct contact (not sure which would be better, but would think
> direct-contact would be). Does anyone have experience with this type of
> mod?
>
> Is there a chance that the above two mods could significantly reduce the
> typical "stock" temp decline during a pull? I have only begun collecting
> parts for a PID, but the first batch of beans that I have used with the
> machine are very finicky, and the temp instability is frustrating. I'll
> have some more MG beans by the end of next week, thankfully.
>
> Any thoughts on these two temp issues would be much appreciated.
>
> Brad




  
Date: 23 Mar 2007 15:23:44
From: seastl
Subject: Re: A few Silvia questions
On 23 2007 09:30:51 -0700, "hbuchtel" <henry.buchtel@gmail.com > wrote:

>Hello Brad, I don't want to get too off subject, but why did you
>choose a Sylvia for your project instead of one of the Gaggia domestic
>models?

Priily because the amount of resources available for "tuning" the
Sylvia far surpassed any other other machine that I had read about.
However, you could argue that it's because it's more of a requisite on the
Sylvia!

>As far as I can tell the Gaggias have two advantages, the group is
>mounted directly on the bottom of the boiler (not off-set like the
>Sylvia) and the pump feed is from the bottom, actually through the
>group (I think).
>
>The boiler is quite a bit smaller and made of aluminium, but if you
>are going to be pre-heating the incoming water that shouldn't be a big
>deal.
>
>Your thoughts?

I agree most definitely about the "saturated" (correct term?) group. I
would really be curious to see what the boiler temperature-to-brew water
difference is on that machine. It seems like the Sylvia's typical 15-18
degree differential is evidence of the thermal instability that does
exist. Most of the modifications related to this focus on making the
differential controllable, so that you arrive at the desired brew
temperature, not at equalizing the two temperatures. Granted, the latter
problem is not so easily eliminated. I would love to design a simple mod
that allowed you to operate the boiler at 203.5 degrees ;-)

One thing that I noticed while googling some info on bi-metal disc
thermostats last night was that the tighter differential thermostats (in
the 2-5 degree range) *all* had current limits of around 100W - 200W.
However, one of these thermostats combined with a relay would be a viable
alternative to PID. However, due to temp overshoot, it may not be anywhere
near the 5 degree band that one would think you'd get with a high-quality
thermostat since it has no anticipation based on fuzzy logic like the PID
would have. I am inclined to believe that someone has probably tried this
before, based on my earlier experiences researching Sylvia tweaks, but I
haven't see any direct mention of it. I'm rambling now though.

Not so sure about the boiler material, but then I am not metalurgist
either. It seems like bronze would be better at "retaining" heat via mass,
but like Greg mentioned earlier, this could be a detriment in some
respects also, such as temperature overshoot tendency. Anyone have
empirical evidence on aluminum vs bronze or brass boilers?

Brad


>Henry
>
>On 19, 11:52 am, seastl <<reser...@later.date.com>> wrote:
>> Hello Everyone,
>>
>> Long-time lurker, first-time poster!
>>
>> I am a recent purchaser and near-future modifier of a Silvia and I have a
>> few questions about the machine.
>>
>> The silvia has a standpipe in the boiler where the brew water exits
>> enroute to the 3-way valve. The brew water is drawn from the boiler
>> approximately 1 inch away from the water inlet (at least that's how I
>> deduce from the illustrated parts listing). Why is this? Would the outlet
>> water temp not be more homgenous if the standpipe were somewhat lower? Has
>> anyone experimented with this? What are the possible ramifications of
>> lowering the inlet?
>>
>> I found a passing mention (can't recall where) of someone either
>> contemplating or actually performing a preheat mod where the fresh water
>> was passed around the boiler a few times before entering it. I was
>> envisioning doing this with 1/4" copper tubing either induction-style or
>> direct contact (not sure which would be better, but would think
>> direct-contact would be). Does anyone have experience with this type of
>> mod?
>>
>> Is there a chance that the above two mods could significantly reduce the
>> typical "stock" temp decline during a pull? I have only begun collecting
>> parts for a PID, but the first batch of beans that I have used with the
>> machine are very finicky, and the temp instability is frustrating. I'll
>> have some more MG beans by the end of next week, thankfully.
>>
>> Any thoughts on these two temp issues would be much appreciated.
>>
>> Brad
>


 
Date: 23 Mar 2007 07:29:49
From: gscace
Subject: Re: A few Silvia questions

Is the boiler insulated in your machine?
>

> Brad

Don't insulate the boiler whatever you do. You want the system be be
"lossy", so that the system recovers from temperature overshoot. This
is an example of where you must think carefully and consult folks who
have done it before. The heating element runs at a higher temperature
than the water when it is operating, and the difference is
considerable when the system is heating up during recovery. There is
enough stored heat in the element to cause a couple of degrees of
temperature overshoot. You want that heat to dissipate into the
surrounding environment as fast as possible. Insulating the boiler
slows that down.

The problem is reduced with feedwater preheat.

-Greg



  
Date: 23 Mar 2007 14:58:10
From: seastl
Subject: Re: A few Silvia questions
On 23 2007 07:29:49 -0700, "gscace" <gregory.scace@nist.gov > wrote:

>
> Is the boiler insulated in your machine?
>>
>
>> Brad
>
>Don't insulate the boiler whatever you do.

I was really more concerned about the PID in shall's machine before I
saw the comments about the fan from DaveB. But it sounds like that's
another discussion altogether!

>You want the system be be
>"lossy", so that the system recovers from temperature overshoot. This
>is an example of where you must think carefully and consult folks who
>have done it before. The heating element runs at a higher temperature
>than the water when it is operating, and the difference is
>considerable when the system is heating up during recovery. There is
>enough stored heat in the element to cause a couple of degrees of
>temperature overshoot. You want that heat to dissipate into the
>surrounding environment as fast as possible. Insulating the boiler
>slows that down.

I can see that. So, shall's fan-cooled PID may even have a desirable
side-effect.

>The problem is reduced with feedwater preheat.
>
>-Greg

Brad


 
Date: 23 Mar 2007 07:18:28
From: gscace
Subject: Re: A few Silvia questions
You might wanna do some measurements and see for yourself what is
going on. However, for the global picture, here's how I'd proceed.
I'd suggest PIDing your machine first, then getting the brew pressure
regulated correctly to 9 bars or thereabouts. Then I'd work like hell
on my technique because use of fresh coffee and consistent technique
are the rate limiters here. They're even the rate limiters for the
PID thing, but since PID is so useful for the Silvia you should just
go and do it.

I'd save standpipe mods and all that stuff for waaaay later. And you
have to think this stuff through very carefully and be prepared to
throw money at it if you're developing a new idea or if you screw up
implementing someone elses.

An example of where you should be thinking things through is that you
should be thinking about where the heat is coming from when you
preheat feedwater, and how effective winding copper coils can be for
feedwater preheat. FWIW, the heat that is warming incoming water in a
set of coils wrapped around the boiler is still the heating element
inside the boiler. The fact that the water temperature entering the
boiler is maybe hotter is probably better with regard to temperature
gradients inside the boiler. The use of coils is much less effective
than people think. Copper coils have to be brazed to the boiler wall
for there to be any significant heat transfer, since the physical
contact between an essentially cylindrical tube with what amounts to
a planar surface is a line, and lines do not conduct heat worth a rats
ass. High temperature epoxies may be suitable, although the surface
will have to be properly prepared for the results to have good service
life. Considering the work involved, if preheat was indicated by
measurement of machine deficiencies my inclination would be to build a
thermoblock to do your preheating or adapt a thermoblock from some
other machine. Then you should ask yourself if it's the coffee you
enhjoy, or is it dinking about with machinery that you like.
Personally I like both, so I do both. YMMV.

-Greg



  
Date: 23 Mar 2007 14:52:01
From: seastl
Subject: Re: A few Silvia questions
On 23 2007 07:18:28 -0700, "gscace" <gregory.scace@nist.gov > wrote:

>You might wanna do some measurements and see for yourself what is
>going on. However, for the global picture, here's how I'd proceed.
>I'd suggest PIDing your machine first, then getting the brew pressure
>regulated correctly to 9 bars or thereabouts. Then I'd work like hell
>on my technique because use of fresh coffee and consistent technique
>are the rate limiters here. They're even the rate limiters for the
>PID thing, but since PID is so useful for the Silvia you should just
>go and do it.

That's kind of where I stand, but my mind is definitely thinking ahead to
some other mods, whether they're necessary or not! Regarding the brew
pressure, what has been the experience with the factory pressure on the
units that come with the OPV? Are they typically higher than 9 bar also? I
ahve a pressure gauge on order, but just curious what is typical.

>I'd save standpipe mods and all that stuff for waaaay later. And you
>have to think this stuff through very carefully and be prepared to
>throw money at it if you're developing a new idea or if you screw up
>implementing someone elses.

The standpipe mod sounds very interesting to me, just from a cursory first
look at the design. However, someone else's experimenting could definitely
save me a lot of time and headache. And I admittedly have only done some
rather simple tests of temperature at the grouphead at this point.

>An example of where you should be thinking things through is that you
>should be thinking about where the heat is coming from when you
>preheat feedwater, and how effective winding copper coils can be for
>feedwater preheat. FWIW, the heat that is warming incoming water in a
>set of coils wrapped around the boiler is still the heating element
>inside the boiler. The fact that the water temperature entering the
>boiler is maybe hotter is probably better with regard to temperature
>gradients inside the boiler. The use of coils is much less effective
>than people think. Copper coils have to be brazed to the boiler wall
>for there to be any significant heat transfer, since the physical
>contact between an essentially cylindrical tube with what amounts to
>a planar surface is a line, and lines do not conduct heat worth a rats
>ass.

These are excellent points, and this is somewhat what I was pondering when
just envisioning the concept. Is induction heating of the coils worth the
cost of the copper tubing? Is brazing (or silver-soldering) the coils
around the boiler (direct contact heating) going to create something that
makes the system inherently less stable than the original?


>High temperature epoxies may be suitable, although the surface
>will have to be properly prepared for the results to have good service
>life. Considering the work involved, if preheat was indicated by
>measurement of machine deficiencies my inclination would be to build a
>thermoblock to do your preheating or adapt a thermoblock from some
>other machine. Then you should ask yourself if it's the coffee you
>enhjoy, or is it dinking about with machinery that you like.
>Personally I like both, so I do both. YMMV.

Pretty much where I am coming from also. Thanks for your feedback. It's
much appreciated.

Brad


 
Date: 22 Mar 2007 23:45:59
From: daveb
Subject: Re: A few Silvia questions
On 22, 11:15 pm, Barry Jarrett <b...@rileys-coffee.com > wrote:
> On 20 2007 09:58:06 -0700, "daveb" <davebobbl...@gmail.com> wrote:
>
> >[a cooling fan is the LAST thing you want on a home espresso
> >machine.]
>
> be sure to remind the cold compensation joint about that, eh?

Will do.

but then, I didn't / don't mount my controllers at the HOTTEST point
in the entire machine.

you judging this year at the show?

dave



  
Date: 23 Mar 2007 07:33:18
From: Barry Jarrett
Subject: Re: A few Silvia questions
On 22 2007 23:45:59 -0700, "daveb" <davebobblane@gmail.com > wrote:

>you judging this year at the show?

dunno. gotta pass the test.



 
Date: 22 Mar 2007 23:44:47
From: daveb
Subject: Re: A few Silvia questions
On 22, 11:15 pm, Barry Jarrett <b...@rileys-coffee.com > wrote:
> On 20 2007 09:58:06 -0700, "daveb" <davebobbl...@gmail.com> wrote:
>
> >[a cooling fan is the LAST thing you want on a home espresso
> >machine.]
>
> be sure to remind the cold compensation joint about that, eh?

Will do.

but then, I didn't / don't mount my controllers at the HOTTEST point
in the entire machine.

you judging this year at the show?

dave



 
Date: 21 Mar 2007 07:30:55
From: daveb
Subject: Re: A few Silvia questions
.

Wow! such hostility! a pity really.

dave



 
Date: 21 Mar 2007 06:01:03
From: daveb
Subject: Re: A few Silvia questions

> > clearly.
>
> I guess installing a few PIDs make you an expert?

No, but installing about 250 of them does.




  
Date: 21 Mar 2007 13:50:27
From: Rob Yokom
Subject: Re: A few Silvia questions

"daveb" <davebobblane@gmail.com > wrote in message
news:1174482063.603614.124840@e1g2000hsg.googlegroups.com...
>
>> > clearly.
>>
>> I guess installing a few PIDs make you an expert?
>
> No, but installing about 250 of them does.
>
>

Hooking up a few wires by no means makes you an expert no matter how many
machines you've done it on, especially when you didn't come up with the idea
in the first place. Assembly line workers build thousands of cars and other
items, but that doesn't mean they know how they work or the theory behind
them. It just means they are practiced in monkey work. Just because you
don't think it's right doesn't mean it isn't.




 
Date: 21 Mar 2007 00:03:23
From: daveb
Subject: Re: A few Silvia questions

>
>


  
Date: 21 Mar 2007 11:17:42
From: Rob Yokom
Subject: Re: A few Silvia questions

"daveb" <davebobblane@gmail.com > wrote in message
news:1174460603.132475.238940@n76g2000hsh.googlegroups.com...
>
>>
>>


 
Date: 20 Mar 2007 14:03:29
From: daveb
Subject: Re: A few Silvia questions
On 20, 2:58 pm, seastl <<reser...@later.date.com >> wrote:
> On Tue, 20 2007 16:46:20 GMT, shall <mrf...@ihatespamearthlink.net>
> wrote:
>
>
>
> >On Mon, 19 2007 16:15:13 -0500, seastl <<reser...@later.date.com>>
> >wrote:
>
> >>It's my first post here, not my first machine. I bought it planning to
> >>modify it from the start.
>
> >>Interesting how some folks translate a little humility into an
> >>opportunity. Speaks volumes really.
>
> >>Thanks for your input, shall.
>
> >>Brad
>
> >Sorry to cause offense. I responded as I did because your post did not
> >say one word about the coffee. Alt.coffee has a long and unfortunate
> >tradition of people whose first response when they don't like their
> >espresso is to blame the machine and then reach for the tool chest.
> >But, a competent barista can make good coffee from nearly any
> >reasonably capable machine.
>
> Ah, ok. No worries.
>
> >I'm not as much of a Luddite as you may think. My Zaffiro was tricked
> >out by Michael Teahan, one of the best espresso technicians you could
> >find: http://home.earthlink.net/~mrfuss/. But, I got to know my
> >machine first, learned to make good espresso from it and then thought
> >about specific improvements I would want.
>
> That's perfectly logical, and I do not disagree. I took a look at your
> machine - I am planning on using the Eurotherm 3216, so I am curious about
> how you've liked your 2132 PID. Is the boiler insulated in your machine?
>
> The Zaffiro looks like a damned fine machine. But I'd guess you don't do a
> lot of steaming, eh? That's a rather large boiler to swing back and forth.
>
> Brad

You may want to speak to jim gallt at pidkits.com.

he can help the do-it-yourselfer.

dave



  
Date: 20 Mar 2007 16:43:53
From: seastl
Subject: Re: A few Silvia questions
On 20 2007 14:03:29 -0700, "daveb" <davebobblane@gmail.com > wrote:

>On 20, 2:58 pm, seastl <<reser...@later.date.com>> wrote:
>> On Tue, 20 2007 16:46:20 GMT, shall <mrf...@ihatespamearthlink.net>
>> wrote:
>>
>>
>>
>> >On Mon, 19 2007 16:15:13 -0500, seastl <<reser...@later.date.com>>
>> >wrote:
>>
>> >>It's my first post here, not my first machine. I bought it planning to
>> >>modify it from the start.
>>
>> >>Interesting how some folks translate a little humility into an
>> >>opportunity. Speaks volumes really.
>>
>> >>Thanks for your input, shall.
>>
>> >>Brad
>>
>> >Sorry to cause offense. I responded as I did because your post did not
>> >say one word about the coffee. Alt.coffee has a long and unfortunate
>> >tradition of people whose first response when they don't like their
>> >espresso is to blame the machine and then reach for the tool chest.
>> >But, a competent barista can make good coffee from nearly any
>> >reasonably capable machine.
>>
>> Ah, ok. No worries.
>>
>> >I'm not as much of a Luddite as you may think. My Zaffiro was tricked
>> >out by Michael Teahan, one of the best espresso technicians you could
>> >find: http://home.earthlink.net/~mrfuss/. But, I got to know my
>> >machine first, learned to make good espresso from it and then thought
>> >about specific improvements I would want.
>>
>> That's perfectly logical, and I do not disagree. I took a look at your
>> machine - I am planning on using the Eurotherm 3216, so I am curious about
>> how you've liked your 2132 PID. Is the boiler insulated in your machine?
>>
>> The Zaffiro looks like a damned fine machine. But I'd guess you don't do a
>> lot of steaming, eh? That's a rather large boiler to swing back and forth.
>>
>> Brad
>
>You may want to speak to jim gallt at pidkits.com.
>
>he can help the do-it-yourselfer.

Thanks, Dave. I did indeed speak to Jim earlier this month, and
fortunately he was open to making a kit with the changes that I wanted.
Sounds like you and he both are staying very busy with these PID upgrades!
I had looked at your installs on eBay and do like them very much. I just
decided early on that I wanted the 1/16 DIN external and his enclosures
looked nice for that. I wouldn't do completely internal on a Silvia where
space is such a premium, although an internal enclosure right above the
steam knob would be sweet if you could insulate and ventilate it properly.

Then again, I do have an old heater fan off a '49 Packard that I'm not
using at the moment... ;-)

Brad


 
Date: 20 Mar 2007 09:58:06
From: daveb
Subject: Re: A few Silvia questions
On 20, 12:46 pm, shall <mrf...@ihatespamearthlink.net > wrote:
> On Mon, 19 2007 16:15:13 -0500, seastl <<reser...@later.date.com>>
> wrote:
>
> >It's my first post here, not my first machine. I bought it planning to
> >modify it from the start.
>
> >Interesting how some folks translate a little humility into an
> >opportunity. Speaks volumes really.
>
> >Thanks for your input, shall.
>
> >Brad
>
> Sorry to cause offense. I responded as I did because your post did not
> say one word about the coffee. Alt.coffee has a long and unfortunate
> tradition of people whose first response when they don't like their
> espresso is to blame the machine and then reach for the tool chest.
> But, a competent barista can make good coffee from nearly any
> reasonably capable machine.
>
> I'm not as much of a Luddite as you may think. My Zaffiro was tricked
> out by Michael Teahan, one of the best espresso technicians you could
> find: http://home.earthlink.net/~mrfuss/. But, I got to know my
> machine first, learned to make good espresso from it and then thought
> about specific improvements I would want.
>
> shall


Actually a fairly absurd implementation of a 'pid' on an espresso
machine.
[a cooling fan is the LAST thing you want on a home espresso
machine.]

Dave
220
www.hitechespresso.com



  
Date: 23 Mar 2007 03:15:46
From: Barry Jarrett
Subject: Re: A few Silvia questions
On 20 2007 09:58:06 -0700, "daveb" <davebobblane@gmail.com > wrote:

>[a cooling fan is the LAST thing you want on a home espresso
>machine.]


be sure to remind the cold compensation joint about that, eh?



  
Date: 21 Mar 2007 01:47:03
From: D. Ross
Subject: Re: A few Silvia questions


 
Date: 19 Mar 2007 18:26:55
From: Marshall
Subject: Re: A few Silvia questions
On Sun, 18 2007 22:52:00 -0500, seastl <<reserved@later.date.com >>
wrote:

>
>Hello Everyone,
>
>Long-time lurker, first-time poster!
>
>I am a recent purchaser and near-future modifier of a Silvia and I have a
>few questions about the machine.

Would you consider being a "recent purchaser, plan to learn how to
work with my machine, might modify it in the 'futurer?'"

I often get the feeling that alt.coffee is a magnet for Popular
Mechanics readers who randomly settled on coffee as the focus for
their mechanical and electrical hobbies. People have made great
espresso with Silvias for many years, with and without PID and other
modifications. As a "recent purchaser," give your machine some time.
Learn its quirks, work on your technique. I predict in a few months
you will be making very good coffee, regardless of where your
standpipe connects to your boiler.

shall


  
Date: 19 Mar 2007 16:15:13
From: seastl
Subject: Re: A few Silvia questions
On Mon, 19 2007 18:26:55 GMT, shall <mrfuss@ihatespamearthlink.net >
wrote:

>On Sun, 18 2007 22:52:00 -0500, seastl <<reserved@later.date.com>>
>wrote:
>
>>
>>Hello Everyone,
>>
>>Long-time lurker, first-time poster!
>>
>>I am a recent purchaser and near-future modifier of a Silvia and I have a
>>few questions about the machine.
>
>Would you consider being a "recent purchaser, plan to learn how to
>work with my machine, might modify it in the 'futurer?'"

It's my first post here, not my first machine. I bought it planning to
modify it from the start.

Interesting how some folks translate a little humility into an
opportunity. Speaks volumes really.

Thanks for your input, shall.

Brad


   
Date: 20 Mar 2007 16:46:20
From: Marshall
Subject: Re: A few Silvia questions
On Mon, 19 2007 16:15:13 -0500, seastl <<reserved@later.date.com >>
wrote:

>It's my first post here, not my first machine. I bought it planning to
>modify it from the start.
>
>Interesting how some folks translate a little humility into an
>opportunity. Speaks volumes really.
>
>Thanks for your input, shall.
>
>Brad

Sorry to cause offense. I responded as I did because your post did not
say one word about the coffee. Alt.coffee has a long and unfortunate
tradition of people whose first response when they don't like their
espresso is to blame the machine and then reach for the tool chest.
But, a competent barista can make good coffee from nearly any
reasonably capable machine.

I'm not as much of a Luddite as you may think. My Zaffiro was tricked
out by Michael Teahan, one of the best espresso technicians you could
find: http://home.earthlink.net/~mrfuss/ . But, I got to know my
machine first, learned to make good espresso from it and then thought
about specific improvements I would want.

shall


    
Date: 20 Mar 2007 13:58:31
From: seastl
Subject: Re: A few Silvia questions
On Tue, 20 2007 16:46:20 GMT, shall <mrfuss@ihatespamearthlink.net >
wrote:

>On Mon, 19 2007 16:15:13 -0500, seastl <<reserved@later.date.com>>
>wrote:
>
>>It's my first post here, not my first machine. I bought it planning to
>>modify it from the start.
>>
>>Interesting how some folks translate a little humility into an
>>opportunity. Speaks volumes really.
>>
>>Thanks for your input, shall.
>>
>>Brad
>
>Sorry to cause offense. I responded as I did because your post did not
>say one word about the coffee. Alt.coffee has a long and unfortunate
>tradition of people whose first response when they don't like their
>espresso is to blame the machine and then reach for the tool chest.
>But, a competent barista can make good coffee from nearly any
>reasonably capable machine.

Ah, ok. No worries.

>I'm not as much of a Luddite as you may think. My Zaffiro was tricked
>out by Michael Teahan, one of the best espresso technicians you could
>find: http://home.earthlink.net/~mrfuss/ . But, I got to know my
>machine first, learned to make good espresso from it and then thought
>about specific improvements I would want.

That's perfectly logical, and I do not disagree. I took a look at your
machine - I am planning on using the Eurotherm 3216, so I am curious about
how you've liked your 2132 PID. Is the boiler insulated in your machine?

The Zaffiro looks like a damned fine machine. But I'd guess you don't do a
lot of steaming, eh? That's a rather large boiler to swing back and forth.

Brad


     
Date: 20 Mar 2007 22:53:17
From: Marshall
Subject: Re: A few Silvia questions
On Tue, 20 2007 13:58:31 -0500, seastl <<reserved@later.date.com >>
wrote:


>That's perfectly logical, and I do not disagree. I took a look at your
>machine - I am planning on using the Eurotherm 3216, so I am curious about
>how you've liked your 2132 PID.

No problems in over 2 years. I adjust it for different coffees over a
range of about 2C. I keep a record of my favorite temperatures for
different blends, which I update occasionally as the roasters change
them with each new crop.

> Is the boiler insulated in your machine?

No. My environmental contribution is to put it on a timer that turns
it off in the evening and back on before I wake up. I work at home a
good deal, and it gets used throughout the day.

>The Zaffiro looks like a damned fine machine. But I'd guess you don't do a
>lot of steaming, eh? That's a rather large boiler to swing back and forth.

No one who drinks a lot of cappas should buy a machine like this. On
the other hand, with a machine like this, you don't need milk to make
a fabulous espresso (See my previous post, if you don't like your own
espressos without a lot of milk, ... :-)

I make one cappa every other morning or so and occasionally for
company.

shall


  
Date: 19 Mar 2007 18:49:27
From: Robert Harmon
Subject: Re: A few Silvia questions
Howdy shall!
But, it is a lot of fun to strip these things down & *hot rod* 'em, isn't
it? And it's a heck of a lot cheaper than restoring a vintage 'vette or
Stickley dining room set. And maybe, just maybe, every once in a while one
can actually improve the performance enough that one's spouse might deign to
notice & comment in a positive vein for a change (not that the Ol' Ball &
Chain ever makes negative comments about *my* hobbies, nooooo, not her.).
--
Robert (Hell, it's just money. What can you do with it if not spend it?)
Harmon
http://tinyurl.com/pou2y
http://tinyurl.com/psfob
http://tinyurl.com/fkd6r

"shall" <mrfuss@ihatespamearthlink.net > wrote in message
news:32ltv25qds8hsdngduib9kiu7ij9fv21oq@4ax.com...
> On Sun, 18 2007 22:52:00 -0500, seastl <<reserved@later.date.com>>
> wrote:
>
>>
>>Hello Everyone,
>>
>>Long-time lurker, first-time poster!
>>
>>I am a recent purchaser and near-future modifier of a Silvia and I have a
>>few questions about the machine.
>
> Would you consider being a "recent purchaser, plan to learn how to
> work with my machine, might modify it in the 'futurer?'"
>
> I often get the feeling that alt.coffee is a magnet for Popular
> Mechanics readers who randomly settled on coffee as the focus for
> their mechanical and electrical hobbies. People have made great
> espresso with Silvias for many years, with and without PID and other
> modifications. As a "recent purchaser," give your machine some time.
> Learn its quirks, work on your technique. I predict in a few months
> you will be making very good coffee, regardless of where your
> standpipe connects to your boiler.
>
> shall




 
Date: 19 Mar 2007 09:26:10
From: Eric Svendson
Subject: Re: A few Silvia questions

"seastl >" <<reserved@later.date.com> wrote in message
news:12vs2601sv2870b@news.supernews.com...
>
> Hello Everyone,
>
> Long-time lurker, first-time poster!
>
> I am a recent purchaser and near-future modifier of a Silvia and I have a
> few questions about the machine.
>
> The silvia has a standpipe in the boiler where the brew water exits
> enroute to the 3-way valve. The brew water is drawn from the boiler
> approximately 1 inch away from the water inlet (at least that's how I
> deduce from the illustrated parts listing). Why is this? Would the outlet
> water temp not be more homgenous if the standpipe were somewhat lower? Has
> anyone experimented with this? What are the possible ramifications of
> lowering the inlet?


See my post about halfway down this page:

http://www.home-barista.com/forums/single-boiler-full-of-water-how-does-it-steam-t3158.html#34138

Modifying the standpipe dimension could be hazardous to the heating
element's life.

How do you know you have a temperature decline during a "pull"? I would say
(from measurements) that most shots would show a temp increase of a couple
of degrees - not that that is necessarily good or bad.

Eric S.


>
> I found a passing mention (can't recall where) of someone either
> contemplating or actually performing a preheat mod where the fresh water
> was passed around the boiler a few times before entering it. I was
> envisioning doing this with 1/4" copper tubing either induction-style or
> direct contact (not sure which would be better, but would think
> direct-contact would be). Does anyone have experience with this type of
> mod?
>
> Is there a chance that the above two mods could significantly reduce the
> typical "stock" temp decline during a pull? I have only begun collecting
> parts for a PID, but the first batch of beans that I have used with the
> machine are very finicky, and the temp instability is frustrating. I'll
> have some more MG beans by the end of next week, thankfully.
>
> Any thoughts on these two temp issues would be much appreciated.
>
> Brad




  
Date: 19 Mar 2007 15:37:09
From: seastl
Subject: Re: A few Silvia questions
On Mon, 19 2007 09:26:10 -0400, "Eric Svendson" <erics@erols.com >
wrote:

>
>"seastl >" <<reserved@later.date.com> wrote in message
>news:12vs2601sv2870b@news.supernews.com...
>>
>> Hello Everyone,
>>
>> Long-time lurker, first-time poster!
>>
>> I am a recent purchaser and near-future modifier of a Silvia and I have a
>> few questions about the machine.
>>
>> The silvia has a standpipe in the boiler where the brew water exits
>> enroute to the 3-way valve. The brew water is drawn from the boiler
>> approximately 1 inch away from the water inlet (at least that's how I
>> deduce from the illustrated parts listing). Why is this? Would the outlet
>> water temp not be more homgenous if the standpipe were somewhat lower? Has
>> anyone experimented with this? What are the possible ramifications of
>> lowering the inlet?
>
>
>See my post about halfway down this page:
>
>http://www.home-barista.com/forums/single-boiler-full-of-water-how-does-it-steam-t3158.html#34138
>
>Modifying the standpipe dimension could be hazardous to the heating
>element's life.

It looks to me like the element could be very much exposed while steaming
(regardless of the standpipe dimensions), and at a much higher element
temperature. Whenever water is evacuated through the standpipe, it should
be being replaced by the pump (in fact the liquid level should increase
immediately as the gas is compressed, and should out-deliver the
extraction water being taken). However, not as efficiently as the steam
wand hot water replenish.

In my opinion, FWIW, the only way the standpipe would play a part in
keeping the element covered is if the 3-way were leaking water overboard
statically, or if your pump were weak to the point that it could not
replace water as fast as an open 3-way depleted it (in which case your
machine would be a paperweight). Then, yes.

A leaking steam valve, which is just as likely as a leaking 3-way, could
steadily deplete the water below the standpipe just from accelerated
evaporation (IMHO). Albeit somewaht slowly.

As I see it - after steaming, one should replenish the boiler via a hot
water draw through the steam wand, correct? As I see it, that is the only
way to properly top-off the boiler again. As such, it should be done
religouly following steaming or any lengthy idle periods. A thing that
should be practiced when auto-refill is not installed, eh. (I assume this
kind of thing is why you really should not leave the machine "on" &
unattended for longer periods).

>
>How do you know you have a temperature decline during a "pull"? I would say
>(from measurements) that most shots would show a temp increase of a couple
>of degrees - not that that is necessarily good or bad.
>
>Eric S.

I agree, and I am guilty of calling it a decline, when it is kind of like
an upside-down ladle. The temp at the portafilter does increase slightly
before decreasing steadily (on my machine anyway). This was just using a
Fluke 189 and a 501K adapter. I am going to look at this again - I may
have done a poor experiment. The biggest issue in my mind is the delta
between boiler temp and shot temp. Not saying I'll even do anything about
it - just learning and evaluating. It's interesting to me, and I
appreciate all the experimenting and testing that you, Andy, Greg and
others have done.

Brad



 
Date: 19 Mar 2007 04:50:55
From: Randy G.
Subject: Re: A few Silvia questions
seastl <<reserved@later.date.com >> wrote:

>
>Hello Everyone,
>
>Long-time lurker, first-time poster!
>
>I am a recent purchaser and near-future modifier of a Silvia and I have a
>few questions about the machine.
>[snip]
>Brad

Take a look at these alt.coffee threads from the Google archives as
they may give you some valuable information, or at least a place to
start:

Tricked-out Silvia
Andy Schecter
Feb 4 2001, 12:43 am
http://tinyurl.com/78eos

Temperature study of my Sylvia (looong)
Greg Scace
Feb 5 2001, 12:50 pm
http://tinyurl.com/awhtp

Proportional Temperature Control for Sylvia
Greg Scace
5 2001, 6:32 am
http://tinyurl.com/7m43d

PI Sylvia Tempmeasurements (really)
Greg Scace
24 2001, 2:39 pm
http://tinyurl.com/d2rof

SCHOMER'S # 27
Prof. Brian L. GOMES da COSTA
May 21 2001, 5:41 pm
http://tinyurl.com/d4lud

Tricked-out Silvia part 3: Procon pump!
Andy Schecter
Apr 15 2001, 1:10 pm
http://tinyurl.com/8crek

Construction, Thermodynamics and heat transfer of espresso machines -
Ok I ranted a bit already
Greg Scace
Sep 20 2001, 1:03 pm
http://tinyurl.com/72omq

Tricked-out Silvia: heated brew head
Andy Schecter
Sep 16 2001, 4:26 am
http://tinyurl.com/ahvf8


Randy "master of alt-c alt-v" G.
http://www.EspressoMyEspresso.com









  
Date: 19 Mar 2007 15:03:25
From: seastl
Subject: Re: A few Silvia questions
On Mon, 19 2007 04:50:55 -0700, Randy G. <frcn@DESPAMMOcncnet.com >
wrote:

>seastl <<reserved@later.date.com>> wrote:
>
>>
>>Hello Everyone,
>>
>>Long-time lurker, first-time poster!
>>
>>I am a recent purchaser and near-future modifier of a Silvia and I have a
>>few questions about the machine.
>>[snip]
>>Brad
>
>Take a look at these alt.coffee threads from the Google archives as
>they may give you some valuable information, or at least a place to
>start:
>
>Tricked-out Silvia
>Andy Schecter
>Feb 4 2001, 12:43 am
>http://tinyurl.com/78eos
>
>Temperature study of my Sylvia (looong)
>Greg Scace
>Feb 5 2001, 12:50 pm
>http://tinyurl.com/awhtp
>
>Proportional Temperature Control for Sylvia
>Greg Scace
> 5 2001, 6:32 am
>http://tinyurl.com/7m43d
>
>PI Sylvia Tempmeasurements (really)
>Greg Scace
> 24 2001, 2:39 pm
>http://tinyurl.com/d2rof
>
>SCHOMER'S # 27
>Prof. Brian L. GOMES da COSTA
>May 21 2001, 5:41 pm
>http://tinyurl.com/d4lud
>
>Tricked-out Silvia part 3: Procon pump!
>Andy Schecter
>Apr 15 2001, 1:10 pm
>http://tinyurl.com/8crek
>
>Construction, Thermodynamics and heat transfer of espresso machines -
>Ok I ranted a bit already
>Greg Scace
>Sep 20 2001, 1:03 pm
>http://tinyurl.com/72omq
>
>Tricked-out Silvia: heated brew head
>Andy Schecter
>Sep 16 2001, 4:26 am
>http://tinyurl.com/ahvf8
>
>
> Randy "master of alt-c alt-v" G.
>http://www.EspressoMyEspresso.com


Randy,

Thanks for that archive of info! I've read some of it and I realize I need
to read more!

One thing that amazes me is that no matter what I envision - it's been
done to this machine...

Brad


 
Date: 19 Mar 2007 06:25:59
From: Andy Schecter
Subject: Re: A few Silvia questions
seastl < wrote:
> The silvia has a standpipe in the boiler where the brew water exits
> enroute to the 3-way valve. The brew water is drawn from the boiler
> approximately 1 inch away from the water inlet (at least that's how I
> deduce from the illustrated parts listing). Why is this? Would the outlet
> water temp not be more homgenous if the standpipe were somewhat lower?

I don't know, however the situation is a least a little more complicated than
that. The heating coil, which is probably slightly hotter than the water,
surrounds the standpipe. I believe the water has to go through the coil on its
way out of the boiler.

> I found a passing mention (can't recall where) of someone either
> contemplating or actually performing a preheat mod where the fresh water
> was passed around the boiler a few times before entering it. I was
> envisioning doing this with 1/4" copper tubing either induction-style or
> direct contact (not sure which would be better, but would think
> direct-contact would be). Does anyone have experience with this type of
> mod?

Sure:
http://i17.photobucket.com/albums/b62/shekk/coilpreheater2.jpg

> Is there a chance that the above two mods could significantly reduce the
> typical "stock" temp decline during a pull?

Certainly the coil around the boiler may somewhat reduce a temp decline. But
that doesn't mean it will produce a better espresso.

I guess it depends on whether your aim is to produce a flat temperature
profile or to produce a better espresso. It has by no means been shown that
the two are related. :-)

--


-Andy S.

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


  
Date: 19 Mar 2007 15:00:03
From: seastl
Subject: Re: A few Silvia questions
On Mon, 19 2007 06:25:59 -0400, Andy Schecter
<schecter@remove.me.rochester.rr.com > wrote:

>seastl < wrote:
>> The silvia has a standpipe in the boiler where the brew water exits
>> enroute to the 3-way valve. The brew water is drawn from the boiler
>> approximately 1 inch away from the water inlet (at least that's how I
>> deduce from the illustrated parts listing). Why is this? Would the outlet
>> water temp not be more homgenous if the standpipe were somewhat lower?
>
>I don't know, however the situation is a least a little more complicated than
>that. The heating coil, which is probably slightly hotter than the water,
>surrounds the standpipe. I believe the water has to go through the coil on its
>way out of the boiler.

I see what you're saying. I want to raise a couple more points.

1. Any time (at least this is how I understand it and I could be all
wet) the water is exiting the boiler via the standpipe, it is going to the
grouphead and the pump is running. Therefore the water is replaced, and
maybe some in addition (albeit the steam wand seems the logical way to
replenish the boiler after a steaming episode). Lower pressure at the
mouth of the standpipe plus higher pressure at the fresh water inlet seems
like the water would migrate directly from one to the other.

2. Also, and I can maybe find the reference again (there's been so
much information on this subj pass before me in the last couple of
weeks...) I did see mention of someone removing the standpipe altogether.
Unfortunately, there was no other details about results, and it may be a
detriment - just asking. The guy did sound like it was a logical thing to
do.


>> I found a passing mention (can't recall where) of someone either
>> contemplating or actually performing a preheat mod where the fresh water
>> was passed around the boiler a few times before entering it. I was
>> envisioning doing this with 1/4" copper tubing either induction-style or
>> direct contact (not sure which would be better, but would think
>> direct-contact would be). Does anyone have experience with this type of
>> mod?
>
>Sure:
>http://i17.photobucket.com/albums/b62/shekk/coilpreheater2.jpg

Looks interesting. Did you implement it completely? What was the result.

The one thing about this type of mod that concerns me is not that it might
not effectively reduce the recovery time of the boiler (which it certainly
should), but that it might effectively increase the recovery time from a
steaming session.

>> Is there a chance that the above two mods could significantly reduce the
>> typical "stock" temp decline during a pull?
>
>Certainly the coil around the boiler may somewhat reduce a temp decline. But
>that doesn't mean it will produce a better espresso.

I couldn't agree more. This is the way I see it, and please feel free to
kick me back inbounds as you see fit, as I definitely value your comments
on this subject. The fact that there is typically a delta temp between the
boiler water temp and the brew water temp at the PF indicates that the
temp stability of the entire "brew path" (FLOABT) is not ideal. If one
could close this gap between the boiler temp running 15 degrees or so
hotter than the resultant discharge water, that would be an improvement in
efficiency, and a desireable thing, IMO. Without the boiler sitting
directly above the grouphead (ie saturated) , this may be a quixotic
adventure.

>I guess it depends on whether your aim is to produce a flat temperature
>profile or to produce a better espresso. It has by no means been shown that
>the two are related. :-)

Well, first please answer me this: If you could achieve a relatively
steady temp during the shot, would this be preferable to a slope (in
either direction) or any other geometrically-shaped profile for that
matter?

A slope to me indicates thermal variations that may or may not be
predictable consistently. I defer to your experience. I just want to take
an entry-level machine to the next level as effectively and efficiently as
possible. The PID is a given. Other mods not so much so. That's why I'm
asking, just trying to learn - not saying one way or another looks best.

Thanks,

Brad


   
Date: 19 Mar 2007 19:49:53
From: Andy Schecter
Subject: Re: A few Silvia questions
seastl < wrote:
> Lower pressure at the
> mouth of the standpipe plus higher pressure at the fresh water inlet seems
> like the water would migrate directly from one to the other.

IIRC, "directly from one to the other" on a normal Silvia means that the water
has to pass through the heating element. But I could have the geometry wrong.

> Looks interesting. Did you implement it completely? What was the result.

It is implemented along with a bunch of other stuff. Each step along the way
made the brew temperatures a little more consistent.

It was disappointing, though. From reading Schomer I had assumed that when I
was able to control the temp within a small range, the espresso would suddenly
get fantastic. This did not occur. It got CONSISTENT, but sometimes it was
just consistently BAD.

To be fair to Schomer, his blend is notoriously sensitive to slight
temperature variations. So extremely good temperature control is very
important for him. But many other blends out there are only moderately
sensitive to temperature.

> The fact that there is typically a delta temp between the
> boiler water temp and the brew water temp at the PF indicates that the
> temp stability of the entire "brew path" (FLOABT) is not ideal. If one
> could close this gap between the boiler temp running 15 degrees or so
> hotter than the resultant discharge water, that would be an improvement in
> efficiency, and a desireable thing, IMO.

With extensive modifications, you can, in fact, get the whole system at a
relatively uniform temperature. That is helpful, but then the more difficult
problem remains: how to become a skilled barista. As Shakespeare said, "A temp
stable machine does not a barista make."

> If you could achieve a relatively
> steady temp during the shot, would this be preferable to a slope (in
> either direction) or any other geometrically-shaped profile for that
> matter?

I don't know. If you can bear more of my prose, see this:
http://www.portafilter.net/2007/01/take-dogma-out-for-walk.html

--


-Andy S.

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


    
Date: 19 Mar 2007 20:54:01
From: seastl
Subject: Re: A few Silvia questions
On Mon, 19 2007 19:49:53 -0400, Andy Schecter
<schecter@remove.me.rochester.rr.com > wrote:

>seastl < wrote:
>> Lower pressure at the
>> mouth of the standpipe plus higher pressure at the fresh water inlet seems
>> like the water would migrate directly from one to the other.
>
>IIRC, "directly from one to the other" on a normal Silvia means that the water
>has to pass through the heating element. But I could have the geometry wrong.

It looks like the top and bottom of the heating element "tube" are open.
If the demand draws water from the upper inlet and down to the standpipe
(and theoretically, this should happen with relatively little blending),
then the water may be *relatively* cold, as the heating element may not be
active, or may not have time to act upon the water. It may not necessarily
appear so at the portafilter, but the 15 degree drop that I am interested
in may be partly from the brew water absorbing heat unnecessarily from the
path on the way to the portafilter, and actually cooling the path. For
that to hold true, the water just inside the standpipe inlet (when water
is flowing to the grouphead) would have to be less than what you're seeing
at the portafilter. This could be tested and would prove or disprove that
the water is absorbing heat enroute to the pf under some conditions.

Here is the image (top of page) that started me thinking about this, but I
admit that your schematic is superior:
http://tinyurl.com/ysk36u
(also a good image or two of the heater)

This may not be as much of an issue if you use the exterior pre-heater
like you conceived, but it could be a contributor to the overall
differential temp on the stock silvia.


>> Looks interesting. Did you implement it completely? What was the result.
>
>It is implemented along with a bunch of other stuff. Each step along the way
>made the brew temperatures a little more consistent.
>
>It was disappointing, though. From reading Schomer I had assumed that when I
>was able to control the temp within a small range, the espresso would suddenly
>get fantastic. This did not occur. It got CONSISTENT, but sometimes it was
>just consistently BAD.
>
>To be fair to Schomer, his blend is notoriously sensitive to slight
>temperature variations. So extremely good temperature control is very
>important for him. But many other blends out there are only moderately
>sensitive to temperature.
>
>> The fact that there is typically a delta temp between the
>> boiler water temp and the brew water temp at the PF indicates that the
>> temp stability of the entire "brew path" (FLOABT) is not ideal. If one
>> could close this gap between the boiler temp running 15 degrees or so
>> hotter than the resultant discharge water, that would be an improvement in
>> efficiency, and a desireable thing, IMO.
>
>With extensive modifications, you can, in fact, get the whole system at a
>relatively uniform temperature. That is helpful, but then the more difficult
>problem remains: how to become a skilled barista. As Shakespeare said, "A temp
>stable machine does not a barista make."

I agree. But that's really irrelevant to the stability issue. Temperature
is demonstrable. Taste is not.

"Good taste is either that which agrees with my taste or that which
subjects itself to the rule of reason. From this we can see how useful it
is to employ reason in seeking out the laws of taste."

-- G. C. Lichtenberg


> > If you could achieve a relatively
>> steady temp during the shot, would this be preferable to a slope (in
>> either direction) or any other geometrically-shaped profile for that
>> matter?
>
>I don't know. If you can bear more of my prose, see this:
>http://www.portafilter.net/2007/01/take-dogma-out-for-walk.html

I like that. The emperor's new clothes, and so forth!

Brad


     
Date: 19 Mar 2007 22:31:27
From: Andy Schecter
Subject: Re: A few Silvia questions
seastl < wrote:
> Here is the image (top of page) that started me thinking about this, but I
> admit that your schematic is superior:
> http://tinyurl.com/ysk36u
> (also a good image or two of the heater)

That page is great. Machines and photos from Taiwan, captions in French.
Formidable!

I made the modification they talk about, routing the inlet water to the bottom
of the boiler instead of letting it in the top.

> This may not be as much of an issue if you use the exterior pre-heater
> like you conceived, but it could be a contributor to the overall
> differential temp on the stock silvia.

I'm repeating, but in my limited experience the easiest method is to get
everything in the flow path at the same temperature. That way you eliminate
the temperature differential as much as possible. This is also the principle
behind the Versalab espresso machine.

--


-Andy S.

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