Yup!! My beloved GS-1 is for sale. Come on, you geeks...where are you? This machine is gorgeous! Will someone please break from the herd before I change my mind!

Here is a rundown:

This is a rarely seen 1989 GS-1 Single Group Solenoid unit and is in fine condition with no need whatsoever for restoration. It has been modified with several improvements to accomplish stable precision thermal control of brewing water during shot delivery. The modifications were done in such a way as to make them easily reversible to return the unit to its fully original state, should that be desired by a collector. There is no rust, corrosion, or crud anywhere and all functions perform perfectly. The group chrome has no dents or scars, the stainless steel panels and the handsome black wrinkle-paint side panels and frame are in great, near perfect condition. Aside from additions required to implement the control electronics, the wiring is the original cloth-insulated and is all in perfect condition. It has a whimsical cup heater which delivers a puff of steam to the cup storage tray on command, as though it's not warm enough up there already!

A pre-heat tank has been added which feeds the original brew tank environment. This third tank is controlled by a mechanical thermostat located in a thermowell and it supplies water elevated to ~204 F to the brew tank. The third tank modification was fabricated and installed by La Marzocco when located in the Ballard district in Seattle in around 2001.

An Omega Micromega CN77000 series auto-tuning temperature controller uses a PID algorithm to exact thermal control over the original brew tank. The Micromega drives an Omega Solid State Relay which modulates power to the brew heating element. The machine has an exceptionally tidy and solid electronics integration with an elegant custom made fan-ventilated stainless steel module holding the splashproofed Omega controller. The extra tank is slung back under the steam tank. The Micromega module hangs back under the left frame rail, easily visible but out of harm's way both thermally and operationally. The pre-heat tank also has a J thermocouple installed for tuning that tank's temperature using a Fluke or other external instrument. That thermocouple could inform a second PID loop if a two-channel controller were installed in place of the single channel Omega.

This is a rare and beautiful La Marzocco machine that played a significant role in researching the importance of temperature stability during shot extraction.

If I were keeping this machine I think I would add another modification that would place an on-delay timer before the pump so that when the brew switch was closed there would be a period during which the solenoid flowed water under only mains pressure to gently wet the coffee load. Then, some few seconds later, the timer would turn on the pump to deliver full extraction pressure. This would bring the machine into the realm of current state of the art in terms of pre-infusion versatility. Also, pressure profiling could be accomplished with a bit of thought and some pump hardware. This would advance the unit another step and place it abreast of certain other machines used in experiments at the frontier of espresso extraction research in the labs of Synesso, La Marzocco, Slayer, and a small number of independent workers around the world. The machine is poised to be a very solid experimental testbed, if so desired.

Comparitively few of the GS-1 Single Group machines were produced by La Marzocco. I should mention that I also have available a Paddle Group neck w/o the brass valve components - just the chrome plated neck. With effort, one could find the necessary valve components and convert this machine into a manual Paddle Group unit. It's potentially a convertible!!

LOTS OF PHOTOS HERE: http://flickr.com/gp/29800684@N07/4h9S3z

This is a trouble-free machine for the hardware aficionato who would appreciate a rare and handsome example from the golden years of La Marzocco innovation and accomplishment, but who would also appreciate state of the art control of water and the very real potential for doing interesting experiments in espresso extraction technology.

$4500 I invite discussion.

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If I had the scratch I'd strongly consider jumping on it. Alas, completing the build-out of my 2nd location comes first! So I'll limp along with my Fiorenzato Bricoletta at home for a spell longer...

Just curious, why are you selling the little beaut'?
miKe mcKoffee aka Mike McGinness said:
If I had the scratch I'd strongly consider jumping on it. Alas, completing the build-out of my 2nd location comes first! So I'll limp along with my Fiorenzato Bricoletta at home for a spell longer...

Just curious, why are you selling the little beaut'?
Let's see if I've gotten this "reply" business worked out...

Your FB has the great functionality and physical beauty of E61 DNA. Have you learned to surf the Farenheit wave to your satisfaction with the unit?

My GS is for sale because I have two storage lockers somewhat full of esoteric collectibles gathered over many years in many obscure interests. I seldom see or use the things hidden away and it's become ridiculous. This was my much-admired home machine until I moved two years ago to a new house where a smaller machine now takes less counter space and has a smaller appetite for kilowatts. And, of course, there is the "scratch" issue for us all these days, isn't there?

miKe mcKoffee aka Mike McGinness said:
If I had the scratch I'd strongly consider jumping on it. Alas, completing the build-out of my 2nd location comes first! So I'll limp along with my Fiorenzato Bricoletta at home for a spell longer...

Just curious, why are you selling the little beaut'?
Shot temps (and quality) no prob' with my retro "garbage can" skinned direct plumbed Bric'. While I had/have the surf down pat via sound and sight the past 4 years on the kitchen counter, made only easier with Eric's digital nose thermometer installed a couple years now. Repeatably and easily hit shot target within .5f. (As verified with Scace of course:-)
Just out of curiosity, does anyone know if you can convert the old gs1 group to a paddle?
I only wish I had the money to take this off of your hands..........this is just beautiful.
Yes, but only if the grouop casting allows for it. Most do.

Chris DeMarse said:
Just out of curiosity, does anyone know if you can convert the old gs1 group to a paddle?
Hi Terry and Chris,
There is at least a difference that involves a group casting feature in the manual neck to allow the placement down through the neck of a rod to actuate the microswitch located below which controls the pump.

Terry, perhaps you know if there is also a difference in the bottom of the neck casting where the valve cup exits through the casting. In the manual group there is a groove there for an o-ring that seals the nipple at the base of the cup at the bottom of the valve body where the cup makes its exit through the neck casting to supply flow to the diffusion block. (This o-ring likes to leak dripwise after it gets hard as rock over time, btw.)

On Terry's site you can view the exploded diagram of a manual group valve body:

http://www.espressoparts.com/GSManualGroup


I'm not certain that the solenoid version is the same there. I have not had my solenoid group apart in that region.

Look at this cutaway to see that the feed tube of a solenoid group joins an assembly that threads down into the neck casting above where the diffusion block threads up into its hole:

http://www.home-barista.com/espresso-machines/cutaway-of-la-marzocc...

So, it may be the case that a manual neck is required turn a solenoid group into a manual group. Or perhaps a part could be machined to thread in and accomodate the o-ring requirement as necessary.

If I'm wrong about this, I imagine that the switching for the pump in a conversion could be cleverly accomplished with a microswitch mounted on top of the group rather than below the group...no need for the rod business. Cyncras have their switches up there in direct contact with paddle cams for actuation :>)

In any case, I have a manual neck casting and access to a valve assembly and a Paddle, so conversion to Paddle is completely within reason.
Barry



Terry Z said:
Yes, but only if the grouop casting allows for it. Most do.

Chris DeMarse said:
Just out of curiosity, does anyone know if you can convert the old gs1 group to a paddle?
I don't know what the interest is for this cool machine, but If i could convert it to a paddel group for a reasonable price I could come up with $3000. Where is it located?
Guy
guypfanz@mac.com (765) 7302935
Thats funny. I think you misunderstand Barry's situation.
I am assuming by your response, Terry, that this machines value is not up for discussion, or am I misreading you?

Terry Z said:
Thats funny. I think you misunderstand Barry's situation.
Oh I'm just guessing, but knowing the price that Barry is currently asking and where he started, I would say the offer is less than Barry would settle for, I know if it were mine ;-) that's how it would go down.



Chris DeMarse said:
I am assuming by your response, Terry, that this machines value is not up for discussion, or am I misreading you?

Terry Z said:
Thats funny. I think you misunderstand Barry's situation.

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