Five Senses Coffee Blog

The Precision Shot Brewer

I’ve been spending quite few hours testing and evaluating various burrs and baskets recently and I have come to realise that a purpose built, highly stable shot brewer would be a useful tool. It may be my metrology background but I am always looking for ways to remove uncertainties and subjectivity from my test procedures so a Precision Shot Brewer is now top of my wish list.

The machine will be, in essence an espresso machine without any facility for producing steam or hot water. It will of course need to be very stable in terms of brew water temperature and water pressure and it must also have the ability to replicate the pressure profile of the Synesso Hydra as found in many of our clients cafes. I think I should also have the ability to collect and digitise temperature, pressure and flow rate data for analysis and lastly but very importantly, it must look cool …

For a base to build it all on I am chopping up a chassis from a new three group Synesso Cyncra that had been dropped from the back of a truck and written off. My stainless steel welding skills are best described as ‘amateur hobbyist’ but with enough tries and plenty of grinding I manage to get something to hold together. The overall plan is to have everything from the hydraulic system to the electronic circuit boards fully out in the open or behind perspex guards so we can be mesmerised by the blinking LEDs while we wait for our espresso shot.

If you want to see ALL the pics, check them out at our Five Senses Flickr Site …

Precision Shot Brewer - where's it's up to now

The G90 is almost ready

I’ve just spent a few days at Giesen Coffee Roasters in Ulft, a lovely little Netherlands town situated near the Germany border, to check in on how our fully re-built and refurbished Probat G90 is progressing. Giesen’s Marc Weber and his team of engineers have be working hard on our roaster for some months and the results are spectacular.

The process started with Marc finding the required roaster, which in our case was a 1947 Probat G90, with its cast iron drum in excellent condition. The condition of everything else is largely unimportant as whatever is not thrown away and replaced can be fully restored to new condition with relative ease. The drum was fully striped down to its most basic components and everything went on the receiving end of a sandblaster. Once the dust settles all of the parts are painted and then reassembled with new bearings and seals. All of the existing electric motors are tossed in the bin and replaced with new three phase units. The old Burners and Gas train are also discarded and a new six row array with 96 ceramic burners, three solenoid valves, a pilot burner and regulator fitted. The cooling tray received the same treatment with most of its components requiring complete replacement due to damage and wear. A new Cyclone was manufactured out of 4mm thick steel, which Marc jokingly told me would easily put up with a chaff fire … and if one were to start, just let it burn. I think he was joking…

Our now fully rebuilt and re-furbished roaster stands side by side with a customised Giesen Roaster Control System. The touch screen interface gives us access to the stored recipes that we use to operate the roaster. Once recorded and fine tuned, the recipes allow us to precisely control the power level of the burners, the airflow velocity through the roaster and the drum rotational speed throughout the entire roast duration.

At this stage it looks like the G90 will arrive in Melbourne in eight to ten weeks (sometime in early August).

Hmmm … I guess I better start thinking about how to I’m going to install it.

Richard and Marc Weber from Geisen stand in front of our new 90kg Geisen roaster for the Victorian roastery

The bare roaster

Our roaster in it's original state, prior to the rebuild/re-furbish

Synesso’s new electronics

This photo is the prototype of Synesso’s completely redesigned electronics box. The current relay driver board with separate display board will be replaced by a CPU board that will connect to the SSRs and solenoids through individual relay driver boards (via optically isolated outputs) . The operator interface is a four line LCD display that is used for changing the configurable settings and displaying temperatures and error logs etc.

All the machine’s functions and features are now fully controlled by the software program, which allows the machine to be incredibly versatile and configurable. New features and functions are added by simply updating the machine’s program via the inbuilt USB port.

Some of the features of the software being developed include: reduced temperature  power saving (sleep) mode, shot timers, two stage pre-infusion timers, error and event logging,  shot counters,  hot water spout timer,  auto back flushing, safety time out on pumps and valves and much more.

The fully operational  prototype will be at the SCAA in Anahiem next week, so drop by if you are going to be there and have a close up look at the next generation Synesso.     ~ Richard

Uber Boiler update

Mark Chandler takes the Uber for a sipin.

We’ve now had a good week to play with our new toy and I’m pleased to say that the Uber Boiler more than lives up to our hopes and expectations. The newly updated version 1.5 software makes the unit extremely stable and easy to operate. I will give you a brief summary of its theory of operation.

When first turned on, the Uber will automatically fill and commence warming up until the “prime temp” is reached. The prime temp is measured in the main tank and can be configured by entering a Service Menu within the software. The factory default setting seems to be 91 deg C.  The prime temp is basically the temperature the water vessel will hold while waiting to be used. When the barista is ready to make some coffee he/she switches the machine into Boost mode by pressing and holding the boost button until the desired temperature is displayed in “Boost Temp”. The Uber will now indicate “Boost Heating” while the heater quickly raises the temperature of the water tank to your set temp. While in boost mode, a recirculation pump is running moving water in a loop from the tank up through the font and back into the tank, evenly distributing the temperature throughout the system.  Unlike the prime temp, the boost temp is measured by a sensor near the base of the font, closer to the water outlet.

Once the boost temp is reached, the Uber Boiler’s electronic controller will maintain a stable temperature while the coffees are being made.  When I measured the temperature at the water outlet on the font, I found it to be within .2 of a deg C of the Boost temperature displayed.

When coffee making is finished, the barista places the unit back into prime mode allowing the water tank to be  refilled, reheated and ready for the next customer.

Next Generation Synesso

102_4554, originally uploaded by Five Senses Coffee.

Here are the first photos of the prototype for the new generation of Synesso coffee machine. There are numerous external and internal design changes under development and will be unveiled at the SCAA in two weeks. In this photo you can see the new front panel shape and the piezoelectric timed hot water switch. The grate design on the cup and drip trays is also new. In days to come I will let you know more about these and other features such as the new processor controlled electronics and the pressure profiling system. We will be at booth 2632 at the SCAA so make sure you drop in and say hello.

It’s Über time!

The Über Boiler

I have just installed our first Marco Über Boiler in a stainless steel bench which will serve as a mobile cart for our planned Über Boiler roadshow commencing mid way through next month. After cutting the required 410 x 195 mm hole in the newly purchased bench the unit drops straight in and holds itself  in place under its own weight.  My first observation is that the brushed metal finish of the base unit and the polished stainless steel water font look fantastic.  The production version is much more narrow than the prototype and has a combined display/controller rather than the separate temperature and weight displays.

Connection to the filtered water supply is though a 350kPa pressure reducer.  Attach a 15 Amp plug,  put the drain hose into a bucket,  position the Über grinder along side and we are ready to roll. Over next week or so we will be putting the Über Boiler through its paces using a number of different coffees, temperatures and baristi.  Stay tuned!

Tags: Chemex, Clever Coffee Dripper, Five Senses, Plunger, Über, Über Australia, Über Boiler, Über Project

Synesso Sabre with one Hydra Group!

Today I am upgrading a 3 group Synesso Sabre to have a single semi automatic group and two fully automatic groups. Sort of a Hydra / Sabre hybrid, you could say; it will definitely have the best of both worlds.   This particular machine is owned by well known Adelaide roaster and cafe owner, Mark Barun (The Coffee Barun!).

The first task is to split the group being converted from the water inlet manifold that supplies the flow meters at the point where it connects to its heat exchange pre heating tube. We then build a new water supply assembly which includes a check valve, brew gauge, expansion valve and hose connection. This machine is already fitted with the dual supply hose modification, so the Hydra group will only need a single braided hose.  The Sabre side pump will look after the steam boiler filling.

Once the manual group top has been fitted we can commence the wiring up of the group switches, brewing motor relay and pump motor. As a bonus, I will be fitting a pre-infusion timer also, maybe I should just go ahead and throw in some steak knives…

~rich

Opening shots

Project X

This project is really coming together. For the benefit  of anyone visiting for the first time, I am nearing the end of the construction phase,  combining the complete front boiler assembly from the world’s best commercial coffee machine into the chassis of an Isomac La Mondiale. The result will be an unassumingly compact dual boiler home espresso machine that can boast specifications only found in top of the range commercial machines.  So, after wiring up the Solid State Relays (SSR’s) that will power the brew and steam elements, there is nothing preventing me switching on and pulling some test shots.

The Hybrid Coffee Machine from Five Senses Coffee on Vimeo.

These first shots were excellent. To be honest, I was quite surprised with the stability the low cost PID controller is achieving, with only a small amount of tuning. There is no pre-heating of the brew water, the steam boiler is not insulated and the covers are off.  Initial observations are that there is no more that a deviation (drop) of 1 degree Fahrenheit over the duration of the shot (+/- 1 digit). The PID display only allows a minimum resolution of 1 deg, including whilst adjusting the offsets, a significant weakness.

There is a lot of work ahead perfecting and fine tuning the machine yet.  A pre-infusion timer, a better quality PID and a pre-heating system (low power thermoblock????) are all on my to-do list.

It would also be nice to have a name for it…

~richard

A PID, SSRs and lots of Wire.

Cutting holes in the front panel of a stainless steel coffee machine is always a bit nerve wracking. I  hardly slipped at all in the end.  About 2 hours with a flat file and I had a nice rectangular hole of the correct size for my PID controller.

I had considered locating the PID out of sight underneath the machine and facing rearward or even under the drip tray. My thinking was that this would, with one obvious exception, preserve the standard look of the Isomac La Mondiale. (one of my stated aims) In the end though, its got to be all about the coffee and when it comes to coffee, temperature is king. We must have easy access to the brew boiler temperature display so, in front it is.

The PID and the Steam boiler pressure-stat will both drive its own heavy duty Solid State relay (SSR). The SSRs will in turn will switch the higher current to the elements themselves. I have bolted the SSRs to the underside of the base plate of the machine which will act as a heat sink of sorts though these SSRs will be operating at about 25% of their capacity so I’m not imagining they will get very hot.

The boiler level is contoled by the original Isomac Auto Filling controller. I actually had it all connected up as a test and I got some great steam happening last week.

The brew pump will be controlled by a small relay also bolted to the bottom of the base panel.  Since the steam boiler will fill under mains pressure, you may be wondering why the machines pump could not just have been switched by the Synesso Cyncra brew group switches. The reason is…… I am going to integrate a pre-infusion timer as found in the latest Synesso Hydra (as an option). The timer will take over control of the brew pump via the relay.

The current job is just wiring everything up. It looks like a birds nest at the moment but it will tidy up nicely. I’ve used color coding of the different funtions etc.  All wire is heat resistant of course.

`richard

Steam boiler plumbing.

Its time to install the steam boiler plumbing connections. The Isomac steam boiler has four 1/4″  holes along its top. We actually need to make six connections so I had to add a couple of  Tee connectors and mount the  Vacuum breaker, Safety Valve and Steam Pressure Gauge off the one point. The Water level Probe, Pressure-stat and Steam Valve Outlet fill up the remaining three positions.  The other items are the water filling and the hot water outlet tubes which are both on the left side of the boiler, below the waterline.  The lack of space above the boiler means that I had to make extension tubes to offset and lower level of the valves and pressure-stat before they would fit under the top cover of the machine.  I just need to add some electrics now and will will have some steam. ~richard