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Date: 18 Mar 2007 22:52:00
From: seastl
Subject: A few Silvia questions
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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
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Date: 23 Mar 2007 09:30:51
From: hbuchtel
Subject: Re: A few Silvia questions
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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
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Date: 23 Mar 2007 15:23:44
From: seastl
Subject: Re: A few Silvia questions
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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 >
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Date: 23 Mar 2007 07:29:49
From: gscace
Subject: Re: A few Silvia questions
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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
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Date: 23 Mar 2007 14:58:10
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 23 Mar 2007 07:18:28
From: gscace
Subject: Re: A few Silvia questions
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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
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Date: 23 Mar 2007 14:52:01
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 22 Mar 2007 23:45:59
From: daveb
Subject: Re: A few Silvia questions
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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
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Date: 23 Mar 2007 07:33:18
From: Barry Jarrett
Subject: Re: A few Silvia questions
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On 22 2007 23:45:59 -0700, "daveb" <davebobblane@gmail.com > wrote: >you judging this year at the show? dunno. gotta pass the test.
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Date: 22 Mar 2007 23:44:47
From: daveb
Subject: Re: A few Silvia questions
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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
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Date: 21 Mar 2007 07:30:55
From: daveb
Subject: Re: A few Silvia questions
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. Wow! such hostility! a pity really. dave
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Date: 21 Mar 2007 06:01:03
From: daveb
Subject: Re: A few Silvia questions
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> > clearly. > > I guess installing a few PIDs make you an expert? No, but installing about 250 of them does.
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Date: 21 Mar 2007 13:50:27
From: Rob Yokom
Subject: Re: A few Silvia questions
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"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.
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Date: 21 Mar 2007 00:03:23
From: daveb
Subject: Re: A few Silvia questions
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> >
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Date: 21 Mar 2007 11:17:42
From: Rob Yokom
Subject: Re: A few Silvia questions
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"daveb" <davebobblane@gmail.com > wrote in message news:1174460603.132475.238940@n76g2000hsh.googlegroups.com... > >> >>
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Date: 20 Mar 2007 14:03:29
From: daveb
Subject: Re: A few Silvia questions
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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
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Date: 20 Mar 2007 16:43:53
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 20 Mar 2007 09:58:06
From: daveb
Subject: Re: A few Silvia questions
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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
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Date: 23 Mar 2007 03:15:46
From: Barry Jarrett
Subject: Re: A few Silvia questions
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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?
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Date: 21 Mar 2007 01:47:03
From: D. Ross
Subject: Re: A few Silvia questions
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Date: 19 Mar 2007 18:26:55
From: Marshall
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 16:15:13
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 20 Mar 2007 16:46:20
From: Marshall
Subject: Re: A few Silvia questions
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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
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Date: 20 Mar 2007 13:58:31
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 20 Mar 2007 22:53:17
From: Marshall
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 18:49:27
From: Robert Harmon
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 09:26:10
From: Eric Svendson
Subject: Re: A few Silvia questions
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"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
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Date: 19 Mar 2007 15:37:09
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 04:50:55
From: Randy G.
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 15:03:25
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 06:25:59
From: Andy Schecter
Subject: Re: A few Silvia questions
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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/
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Date: 19 Mar 2007 15:00:03
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 19:49:53
From: Andy Schecter
Subject: Re: A few Silvia questions
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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/
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Date: 19 Mar 2007 20:54:01
From: seastl
Subject: Re: A few Silvia questions
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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
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Date: 19 Mar 2007 22:31:27
From: Andy Schecter
Subject: Re: A few Silvia questions
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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/
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