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Rancilio Silvia V3 (Part 4/4) – Tools and Latte Art Practice
After PID upgrade, I don’t have to worry about the temperature and I can finally focus on Latte Art and taste improvement. I will keep updating this, come back to see my progress especially on latte art. If you have invested so much money on Rancilio already, you may as well get the best of all the accessories. Here is the rest of my upgrade:
- PID with steam control - Strongly recommended, read my previous article
- Reg Barber Espresso Tamper + Rubber mat – Total around $100 Zuccarini (Toronto) It is strongly recommended
- VST Precision filter basket 18g (double shot) - $29 CAD Social Coffee (Toronto) To improve the taste of the latte, I bought a VST Precision filter basket (Google it) – It DOES make a HUGE DIFFERENCE in taste by making the espresso less bitter and smoother, it’s absolutely amazing. VST is a must buy.
- Espro Toroid 591ml, 20 oz. milk pitcher $38 CAD + Thermometers $15 CAD Green Beanery (Toronto) It is called a CHEATER pitcher, I didn’t know until I bought it home. It is designed to cheat by just hold the steam wand right in the middle for the whole time due to the special design at the bottom. Well, to me it’s a marketing gimmick since you can’t skip stretching (sucking air) step, and you will lose the real Barista skill if you use this all the time. I bought it because of its built quality and I just use it as a regular stainless steel pitcher using the traditional milk steaming method. Do not buy, way overpriced and it’s a gimmick.
- Brew head flat shower screen – $19 US PID Silvia (online via Bonanza.com) I would say this is totally optional if you have the VST Precision filter, since VST doesn’t leave a lot of residue on the screen. However, if you are using 40-100-102 Rancilio stock filter, this would make cleaning much easier
- Naked Bottomless Portafilter – $59 US PID Silvia (online via Bonanza.com) This is an excellent tool for troubleshooting the espresso extraction, then adjust other variables based on the color and flow of the extraction. The pattern you are looking for is called “tiger stripes”. It is strongly recommended, this is an excellent article “Troubleshooting Common Espresso Problems“.
- Cafelat Cleaning Brush – $16 CAD 49th Parallel Roasters This is an optional tool, but this seems to make grouphead cleaning easier.
- Scottie Callaghan (SCDT3) Dosing Tools – $39.95 CAD 49th Parallel Roasters If you are using VST precision filter basket, this is a MUST tool to have. Read this
Can These Filters Change the World of Espresso? and you will know why. Trust me, VST filter basket is not ordinary filter, you need to make the dent in order to make a perfect espresso. Although I could have made the DIY version using cardboard/plastic, but after reading Scottie’s web site how he spent 6 years to develop his skills and tools, I decided to support him and bought a 3-piece set.
Adjustment after Upgrade
Because of VST filter basket + naked bottomless filter + flat shower screen upgrade, the extraction time changed quite a bit. After making 20+ espresso and latte, I re-adjusted everything and I can make pretty good shot consistently. Note that for different beans, all settings have to be changed.
- Bean: Lavazza Qualita ORO – 100% Arabica
- Rocky Doser setting: 3 (fine grind)
- PID Temperature: 222 F
- Dosing weight: 20 g on VST (use a digital kitchen scale)
- Collapse: 4 times (as per Scottie’s suggestion)
- Scottie Dosing Tool: #3
- Final Weight: 19 g on VST
- Tamper pressure: 25-30 lb
- Extraction Time: 25-28 seconds
- Milk temperature: 140 F (1% or 2% milk)
Rancilio Silvia V3 (Part 3/4) – Water Pump Leaking and PID Upgrade
Week 5: Rancilio Silvia V3 – PID Upgrade
I only had Silvia V3 for about a month and I decided to unleash the ultimate power of this machine. There are reasons behind the upgrade, first of all temperature surfing in both espresso and steam are totally fine if you have read my previous blog Temperature Surfing and Microfoam (Part 2), but it’s very time consuming. Imagine you have friends at your place, it will probably take 1 hour just to make 5-6 latte because of the boiler cycle. The other reason is the temperature control of PID is way more precise than surfing, so you can have more consistently perfect shots . Lastly, it looks cool with the digital thermometer display.
Choosing the PID for Silvia
There are so many PID kits on the market for Silvia, there are certain criteria I had:
- Safety and Reliability: Major parts of the PID kits such as SSR (Solid State Relay) and digital temperature controller must not be Made in China. If I am spending the money on the Italian made machine, why would I want some unreliable or low quality parts on Silvia?
- Void warranty: Any PID kit requires soldering, drilling or cutting existing wires are not in my consideration. The whole kit should be reversible in case of warranty work
- Steam Control: Without the steam control, PID kit is much cheaper because you will still be using the factory thermostat. In that case, you can read the digital temperature display and determine when to start steaming right before the indicator light turns off. However, if you miss it you have to wait for another cycle. With steam control, you will never miss the cycle because PID turns on the boiler automatically when the temperature drops
- Timer Control: For me, PID should only control the boiler/steam temperature, not the time of the extraction. Some PID kits let you preset as 25 seconds for extraction by clicking a button, personally I don’t like this. So, pre-infusion is not on my list because I want to keep the machine as “manual” as possible – I only need PID to help me to narrow the “deadband”.
- Looks Good: It has to look good overall by matching Miss Silvia high fashion sense in stainless steel. No aluminum case.
- Power supply: No additional power supply needed
There are several famous PID kits for Silvia V2 or V3:
- MLG PID Kits – with Steam control – $330
- PidSilvia.com – $120 to $240
- Auber Instruments pre-infusion – $245
PID Kit Arrived and Installed
Well, you may not have the same requirements that I have, for me I chose MLG PID Kits. The kit arrived and everything (controller, SSR and even all the cables) was in extremely high quality build and installation guide included were very clear and detail. Notice that the photos in the instruction were for Silvia V2, but it applies to Silvia V3 since Ranchilio has not change one thing. Both Watlow controller and SSR were Made in U.S.A. with hard copy manual included.
Installation was pretty easy, it took me 4 hours to install. It should not have taken that long but I just wanted to make sure everything was perfect without breaking anything, see the photos below for my installation in progress, the step-by-step installation guide was in color PDF and I loaded it on my iPad.
Water Pump was Leaking
Notes: Water Pump leaking has NOTHING to do with MLG PID Kit, it was Rancilio crappy quality control and/or parts. Perhaps, they fool customers by giving out refurbished machines and sell them as new.
At the end of the MLG PID Kit installation, I did a test run. I was shocked to see that the joint between the metal and plastic fitting of the ULKA EP-5 was leaking whenever the pump was on. No wonder why in the past weeks, I got some water on the table! Originally I thought I didn’t put the drip tray properly, now this explained why.
For minor leaking like this, it can be fixed easily. Since I didn’t know if that fitting was a forced fit or it was a threaded fit, I couldn’t find any information on the Internet. So, I tried using the “Nashua Stretch & Seal” (or “Magic Wrap”) and it failed so badly. I think the powerful pump produces quite decent pressure, this type of seal has NO WAY to hold the pressure of 10 bar (145 PSI) or above.
The seal used by Rancilio was hardened on brand new machine?
Next, I tried to unscrew them – Yes it was a threaded fitting. Then, some green stuff (see in the photos) felt off from the threads! It is very hard to believe the seal has already hardened because my machine was brand new. Now it makes me think that Rancilio or the store sold me a refurbished machine and charged me the price of a brand new one. This really bugged me. Anyways, life goes on…
Fixing this was extremely easy, I used a product called “Pipe Stick” (or any pipe joint compound, even teflon tape would work too) because I used that to fix a swimming pool pump before. Also, the product claims it can withstand up to 2000 PSI. Everything was fixed after an additional hour of work and no more leaking!
Using the PID
PID is extremely simple to use, the preset temperature by MLG for espresso brew was set to be 106C / 224F (for cold machine starts). The instruction suggested if you have warmed up the machine for 30 min or above, you can set the PID to be 105C / 222F (This is the latest notes provided by MLG, the older note said 226F as default) . As for steam mode, the preset is 146C / 295 F meaning that if the boiler temperature drops below that point, the boiler will start again in full power. The temperature usually will keep climbing till 148C / 300 F to 154C / 310 F at max.
Conclusion
PID makes life so much easier by saving time and water, most importantly it gives you repeatable good result consistently. I strongly recommend to get one for your Rancilio Silvia, you paid for what you get for MLG PID Kit although it is a bit expensive but it does worth every penny.
Rancilio Silvia V3 (Part 2/4) – Temperature Surfing and Microfoam
After getting some horrible taste espresso and unpredictable microfoam, I realized that there are still a lot to learn in using Rancilio Silvia V3. I followed many videos and forums on the Internet and combined with my trial-and-error experience, this is what I want to share. Note: Coffee bean selection and Latte Art pouring technique are not in this scope of this article. Hope this can help other Silvia users who just bought the machine.
Welcome to Canada: Fahrenheit or Celsius?
Being a Canadian, I am so confused about the use of Fahrenheit vs Celsius, because for all the kitchen related stuff such as oven and cookbooks, Fahrenheit is being used. But when you turn on the TV for weather forecast, they use Celsius. Speedometer in cars and road signs are in Kilometers, while almost everything is in inches/feet at Home Depot. This is one thing Canada really screwed up so badly, because historically we are so tied to UK but geographically we are next to US. The mix of Metric and Imperial measurements is really common, yet it’s stupid. Since coffee belongs to kitchen, I decided to use Fahrenheit.
Week 2: Understanding Miss Silvia
On week 2 after I bought the machine, I started to read more articles and videos on Internet (the user manual came with the machine was pretty useless). First of all, you need to understand Silvia is a SINGLE boiler machine, that means the boiler is used by both espresso brewing and steam. Let’s understand how Miss Silvia works when you turn on the brew button. In summary this is the CYCLE:
- Boiler indicator=ON (Boiler is on when temperature is below 86 C/186 F)
- Boiler indicator=OFF (Boiler is off when temperature reaches 102 C/215 F)
- Boiler indicator=OFF (Even boiler is off, the temperature keeps climbing until 116 C/240 F exactly 30 seconds from previous stage. Then boiler starts to cool down)
What is the problem here?
Because espresso is very temperature sensitive, the espresso or latte would result in either too bitter or too sour. The best temperature for brewing coffee at the portafilter is 198 F to 204 F (92 C to 95 C). Without proper technique, you don’t really know what’s the best time to press the brew button. This is called “dead band” problem, most lower end Italian single boiler semi-auto espresso machines have this problem, such as Faema, Gaggia, etc. For more information about “deadband”, there is a very well written article Defining Deadband and Boiler Cycle on CoffeeGeek.com.
There is a temperature offset between portafilter and boiler temperature, and also when the cold water comes temperature drops. If you start brewing your espresso at stage (2) when the indicator = OFF (boiler temp at 102 C/215 F), the temperature drops so quickly as soon as cold water comes in and boiler starts again at 86 C/186 F. In this case, your espresso will taste really sour because of low temperature.
Brew Espresso – Temperature Surfing
To overcome the deadband problem, we need to use a technique called “Temperature Surfing”. The basic requirements are:
- This procedure is for cold start (the machine in room temperature for 6+ hours)
- Grinding, tamping and cup warming are assumed to be done properly
- If espresso brew is right after STEAMING session, you need to run at least 30 seconds of cold water to bring down the boiler temperature to cool stage, otherwise the temperature surfing will not be accurate
Procedure:
- Warm up the machine for at least 30 min (or brew at least 2 x double shot espresso and throw them down the drain)
- Current State: Indicator light = OFF
- Turn ON brew button to run cold water into boiler until indicator light is ON
Reason: Cold water makes the boiler temperature drop and triggers the boiler to start again when temperature is below 86 C/186 F - Wait till the indicator light = OFF and immediately start a stop watch (iphone or watch). Now, the boiler temperature is 102 C/215 F
- Precisely wait for 30 seconds
Reason: The internal temperature keeps climbing because of pressure inside the boiler even the boiler is turned off. It reaches at 116 C/240 F (which is 30 seconds) and boiler starts to cool down by itself - Turn ON brew button to run cold water into boiler for 5 seconds.
Reason: This procedure is called “cold flush” to bring down the temperature to 110 C/ 230 F, you should see a lot of steam in first 3 seconds * - Turn OFF brew button (stop watch at 35 seconds)
- Put the portafilter + cup under the brew head (You have 15 seconds time)
- Turn ON brew button (stop watch at 50 seconds)
Note: At this point, cold water comes in continuously for the next 25 seconds + temperature offset between the brewhead and boiler, so the final average temperature would be ideal when it touches the coffee which around 198 F to 204 F (92 C to 95 C) for the next 25 seconds. - Reset stop watch and start it from 0 (Stop watch at 0 seconds)
- Your espresso should starts brewing, if tamped and grind properly, your espresso should finish at 25-30 seconds (Stop watch at 25 seconds)
Note: the boiler indicator light = OFF all the time until the end, the indicator light will turn ON automatically at around 20 seconds ** - Turn OFF brew button at 25-30 seconds, depends on coffee, tamp and grind
* If you don’t see steam, your machine has not been warmed up enough in (1)
** If you don’t warm up in (1), the boiler isn’t hot enough and the boiler starts to kick in too early, giving you the wrong temperature.
What’s the right taste?
Perfect balance between sour and bitter. To troubleshoot your espresso, there is a very detailed article Diagnosis of Extraction Problems on home-barista.com. In summary, here is the combination of the potential issues between temperature, tamping technique and grinding settings:
- SOUR = Temperature too low / Extract too fast (grind is too coarse or tamp is too light)
- BITTER = Temperature too high / Extract too slow (grind is too fine or tamp is too heavy)
Week 3: Microfoam and Latte Art Challenge
After learning proper technique to make the best shot of espresso, I started to face another big problem in Silvia: Steam and Microfoam. If you have read the article at home-barista.com, you will not be surprised about the steaming performance is one of the weakness of Miss Silvia. Most beginners using Silvia would get really frustrated because some days the microfoam are good but some days are so bad. Don’t give up, continue reading I experienced the same too.
Understanding Miss Silvia in Steaming
Similar to espresso brewing, we need to first understand Miss Silvia operations:
- Brew button = ON: Boiler is ON (if temp is right) and water pump is ON
- Hot water button = ON: Boiler is ON (if temp is right) and water pump is ON
- Steam button = ON: Boiler is ON (if temp is right) and water pump is OFF
The MOST IMPORTANT part here is (3). The water pump is OFF when steam is ON, meaning that you have to FILL the boiler every time in order to get maximum steam performance. Lack of steam = not enough spinning whirlpool = bad microfoam.
Silvia Steam – Temperature Surfing
If you search on Internet, many suggested to start the steaming before the indicator light goes out so that the boiler keeps heating during the whole streaming session, this is the only way to get maximum steam from Silvia. So, how do you know when is “before”? That’s why we need temperature surfing even for steam!
Procedure: Rancilio Silvia V3 (steam wand with one hole)
- Make at least one espresso using the steps above before start steaming milk
- Turn ON Hot water button
Reason: Silvia does not have auto-refill feature, you need to fill the boiler with water manually to ensure maximum steam power (repeat for every session) - Open the steam valve and let water out
- Close the steam valve
- Turn OFF Hot water button
Note: At this point, the boiler is filled with water - Current status, indicator light = OFF (if not, wait until it’s off)
- Turn ON Brew button, run cold water until indicator light = ON
Reason: Similar to brew coffee, we need to surf the boiler at the lowest temperature - Turn OFF Brew button
- Turn ON Steam button (Start stop watch at 0 seconds)
- At 1:00 (1 min), open and close the steam valve with 1/10 turn and start slowly bleeding out water from steam wand. Open/close motion for 4-5 times.
Reason: This step is called “bleeding” to make the steam as dry as possible - At 1:20(1 min 2o seconds), Close the steam valve and stop bleeding water from steam wand. Don’t worry about the steam is not dry enough, continue next step when it reaches 1:20
- At 1:45 (1 min 45 seconds), Open the steam valve Start steaming the milk
Note: The indicator light should be ON when you start steaming, and it should remind on through out the steaming session
If you pass 1:45 mark, the boiler may shut off and you won’t get maximum steam power. Without max steam power, you cannot spin the milk in whirlpool fast enough and not able to create good microfoam.
Microfoam Technique for Silvia V3
- Use cold milk from the fridge
- Put the steam wand tip 0.5″ below the milk, 1″ away from the wall. Tilt the pitcher at the right angle, everyone is different. So, practice with water to get correct position before using milk
Reason: If you put it on the surface to start, milk will splash everywhere - Open the steam valve with 1/8 turn slowly. You will hear loud screaming sound in the beginning
- Open the steam valve with another 1/8 turn (totally 1/4 turn)
- The milk should start in spinning in whirlpool motion
Note: The steam tip will get out of the surface as the milk starts spinning, now you need to adjust the pitcher to keep the steam wand tip just touching the surface of the milk. The KEYWORD here is “touching the surface” (0.1″ – 0.2″ below the milk) - Surf the tip on the surface of the milk, and lower the pitcher to get frequently chirping (tch tch tch) sound as the milk volume grows.
- Too much sound = WRONG = tip too far away from milk = too much air being sucked in = bubble too big (For Cappuccino)
- Too little chirping sound = WRONG = tip too deep in the milk = not enough air sucked in = not enough bubble (Hot milk only)
- Frequently chirping sound = CORRECT = good balance of air sucked in = good microfoam bubble (For Latte Art)
Reason: the chirping sound is the indication of sucking small air into the milk.
- Continue to lower the pitcher as the volume grows and get frequently chirping sound until milk reaches 37 C / 100 F
- Now, second stage of Texturing starts
- Put the steam wand tip 1″ into the milk, 0.5″ away from wall while it is still spinning. Now, we don’t want to be “on the surface” or “surf” anymore. In other words, put the ward deeper and closer to the wall (closer to wall = spin faster)
- Open the steam valve with another 1/4 turn or 1/2 turn to blast the steam out, now the milk should spin very crazy in whirlpool motion. Lower the pitcher so that the tip is consistently below the milk (do not suck air).
Note: At this stage, You should NOT hear any chirping sound or screaming noise, and it should be VERY quite. If you here screaming sound or low pitched roar sound, see troubleshooting section. - Close the steam valve and stop steaming when milk reaches 60 C /140 F
- You should get decent microfoam. You can continue to steam another pitcher of milk and get consistently microfoam as long as you follow all the steps above again. Remember to re-fill the boiler with water.
In summary, there are 2 stages:
- Stretching - Tip surfing on milk by sucking air into milk creating micro bubble
- Texturing – mix the air bubble with the rest of the milk (No more sucking air)
According to the information, cold milk (below 37 C / 100F) creates small bubble, warm milk (above 37C / 100F) creates big bubble. That’s the reason why we have 2 stages.
Milk Frothing Troubleshooting
If you hear the loud screaming noise or low pitched roar sound during the steaming session:
- Steam power is too low, make sure you fill the boiler and starts steaming at 1:45 with indicator ON through out the steaming session (instructions above)
- The whirlpool spinning is too slow, open the valve 1/6 turn instead of 1/8 (each machine may be slightly different)
- The angle of the steam wand or angle of the pitcher is wrong, try different angle so that it creates spinning motion, practice with dish detergent+ water
- You are putting the steam wand too deep into the milk just keep 0.5″ while milk is spinning very fast in whirlpool motion
- MOST IMPORTANTLY, If you don’t have enough air sucked in the 1st stage, you will get very loud screaming noise in 2nd stage
If your microfoam is not rich/thick enough:
- You need to suck a bit more air in 1st stage = more chirping sound is needed
- You are not surfing on the surface in 1st stage, your steam wand is below the surface of the milk all the time
- Your milk whirlpool spinning is not fast enough
- Milk selection: Skim milk/1% is thinner than 2%/whole milk
Milk Selection
Milk plays an important role in microfoam. If you do a search on Google you will get very confusing result on this topic. Some people said skim milk / low fat 1% is better in making microfoam while some said 2% / whole milk.
The fact: ALL milk, all brand, all freshness can be made into the same thickness and same shininess if you have the proper technique.
For skim milk/1% to get the same thickness as 2%/whole milk, you need to introduce slightly a bit more air in stretching stage. Also, you may want to play with the timing too, you can also try spending more time in stretching than texturing.
My suggestion is to buy several bags of skim milk and several bags of whole milk. Use the SAME technique (same timing) and experience yourself. This is the only way you can learn by adjusting your own skills. My personal preference: 1% Milk since it has a well balance between taste, healthy and latte art. Although skim is healthy, but it does make the latte taste really horrible.
More confusion when you read more – Stick with one method
There are some videos show you that you don’t need to make milk spin during 1st stage of stretching, and whirlpool is only needed in 2nd stage of texturing. Well, there is always multiple ways from point A to B, you can try. Also, depending on how do you use the microfoam. Is it just purely for cappuccino or latte art?
When you watch those microfoam technique videos, different machines require slightly different technique, such as steam power, 3 hole vs 1 hole and pitcher shape. For exmaple, Espro Toroid requires you to hold the steam wand right in the middle for the whole time.
Some videos on YouTube even tell you to open the steam valve fully in the beginning, I can tell you that this is very wrong for Silvia. This will result loud screaming noise or low pitched roar sound in texturing stage, I guarantee. Simply Rancilio Silvia is not a real professional grade machine, this particular move will only work on machines with unlimited supply of steam. More importantly, open too much in the beginning make the temperature goes up too fast, and if you are not experienced you don’t have enough time to suck enough air. DO NOT open fully for Silvia, follow what I wrote in the steps above.
Conslusion
My goal here is to prove Rancilio Silvia V3 is capable of making very good espresso as well as Latte Art if proper technique is used. Don’t give up if you just bought one, it does take time. As you can see the photos below, I got some improvement over the several weeks of practice to make some sort of Leaf/Rosetta and Heart (due to my limited latte art skills). Skim milk, 1%, 2% and whole milk were used as shown in photos.
(Photos were taken using Canon DSLR and iPhone, so quality is not consistent)
Rancilio Silvia V3 (Part 1/4) – General Review and Log
Deb and I have been using the Nespresso – Citiz and Milk machine for almost 2 years and it’s time to explore the coffee world a bit more. Also, I was a bit frustrated because I couldn’t make latte art like the pros using Nespresso Aeroccino.
We did a lot of research and found that Rancilio Silvia is one of the most popular machines in “prosumer” or “semi-pro” category that falls within our budget. Since it has very good reviews on the forums and NOT made in China, we decided to order one online. We searched everywhere and found a good package deal “Rancilio Silvia V3 and Rancilio Rocky Doser” that does free shipping within the Canadian soil.
Why Rancilio Silvia?
Price and Quality – the outcome of the coffee (espresso and latte) is comparable to the coffee made with a $3000 machine. Another reason is because it’s made in Italy, just like Prada or Gucci.
Is Rancilio Silvia for everyone?
No, Rancilio Silvia is classified as “semi-automatic” coffee machine by the industry. If you ask my opinion, I would classified it as “manual”. I would say Silvia is a machine that you need to spend a lot of time on it, understand how it works in order to make a decent cup of drink. Especially in the beginning (couple of weeks/months at least), there is a learning curve. Just like you learn how to drive a manual transmission car or start using a DSLR camera, it’s a matter of time. I am not surprised that many people would back off or even return the machine as it is NOT as easy as to just push a button like Nespresso. However, if you can drive a standard car smoothly and/or taking DLSR photos properly without using “P” or “Auto” mode, Silvia is probably right for you.
Note: Before you buy this machine, please beware that you need to spend MORE than just the machine alone, you are prepare to INVEST at least $500-$800 US on top of that. I am not going to discuss that, there is a lot of information on the Internet. At minimal, burr grinder is a must. Recommended: milk pitcher, thermometer, Reg Barber tamper and tamper mat. Optional: knock box, naked/bottomless portafilter, PID Kit, VST 18g Filter Basket and brewhead flat screen.
Week 1: Package arrived but Rocky Doser was Broken
The package arrived and we opened the boxes happily, we found there was an interesting note inside: “Dear Customer, we test all our Products. The coffee grinders you purchased was tested with real coffee beans. Although it was cleaned thoroughly, coffee powder may still be present. Thank you for your understanding”
At first, I thought it was the trick planted by the store who sold us the machine, and they tried to get rid of the used/returned machines. After verification with several web sites and forums, that’s the normal Italian way to do QA. Okay… I was a bit speechless.
Next, I carefully examined the doser, there was a plastic on the chute was broken. Yes, it’s brand new! I called the store and they were very helpful and promised to contact Rancilio US to send me the replacement parts. In the mean time, the solution was to use masking tape and aluminum foil to patch it! I could still use the doser, but it was a bumpy start.
Update (After 3 months): With many phone calls and follow up emails to deal with the store to get the warranty replacement parts, I FINALLY received the 38-123-032A Rocky Hopper – Blue. Unfortunately, it doesn’t come with the Rancilio label.
Burr Grinder Important Notes:
- A lot of sites and forums warned already – You should only change the settings of Rocky grinder when the unit is powered ON and burrs is in motion. If it breaks because of this, it is NOT covered under warranty
- You need to use Italian espresso coffee beans ONLY. If you use Starbucks beans for example, the beans will get stuck and also the non-Italian beans are too oily and it is not good for the machine. Read this 1st-line.com – Rancilio Rocky (Read Notes in the middle of the page)
On the first week, I was able to pour some Latte but the art looked like shit. Not only I wasn’t able to make proper microfoam, the Latte actually tasted so bitter. (Continue to read next part for improvement… )
(Photos were taken using Canon DSLR and iPhone, so quality is not consistent)
Reviews and References
- CoffeeGeek.com – Rancilio Silvia Espresso Machine: The first look
- Home-barista.com – Rancilio Silvia Flash Review
- Ranciliosilvia.org – Rancilio Silvia V3 Review
- MakingEspresso.com – Miss Silvia Review
Entity Framework – Table Per Hierarchy (Single Table Inheritance)
In the past, I have worked with some ORM software such as X-tensive DataObject .NET, which generated the database schema based on the Entity models. This type of ORM is called Table-per-Type Inheritance, i.e. each table is mapped to single Entity in the model (*note 1).
However, this doesn’t always work if we have an existing database or we want to maximize the performance of the relational queries or we want to save space in database. In many cases, we don’t want the relational database to look like the Entity model.
Entity Framework supports Table-per-Hierarchy Inheritance, i.e. different types in the Entity model that inherits from a base class and all mapped to a single table (*note 1).
This is an extension to the articles I found on the Internet:
- Inheritance and Associations with Entity Framework (Moses’s Blog)
- Single Table Inheritance in Entity Framework (Zeeshan Hirani)
(*note 1 were quotes from Moses’s Blog)
School Example
Let’s look at a very traditional “Person”, “Student” and “Instructor” example, I have created a simple database. With “PersonTypeID” defined as a foreign key in a separated table and this is the major difference from the 2 links above.
In Visual Studio 2010, I used the “Generate Model from Database” to create the initial EDMX file for my web application. It helped 50% of the work and I strongly recommended. Yet, there are some manual work to do because Visual Studio doesn’t know what the conceptual level would look like.
At this point, it is pure relational-to-object. If you start coding in LINQ, it’s like LINQ-to-SQL. However, our objective is to make it object oriented. So, let’s add 2 new Entities in the design tool, namely “Student” and “Instructor” which inherits from base class “Person“. Also, we have to delete the “HireDate” and “EnrollmentDate” from PERSON entity and reproduce the 2 properties.
If you compile right away, you will get the error:
Error 3005: Problem in mapping fragments starting at line xxx:Must specify mapping for all types in…. An Entity with Key (PK) will not round-trip when: Entity is type [xxxxxxxxx.yyyyyyyyy]
Conditional Mapping
To fix this, we have to add conditional mapping for the 2 Entities (Student and Instructor). This tells the engine to save the value 1 (PersonTypeID) to database (Person table) when we create a Person object.
We now have the conditional mapping. Let’s compile again, but you will get this error:
Error 3032: Problem in mapping fragments starting at line xxx:Condition member ‘Person.PersonTypeID’ with a condition other than ‘IsNull=False’ is mapped. Either remove the condition on Person.PersonTypeID or remove it from the mapping.
In conceptual world, we don’t actually need to use “PersonTypeID” since we have already used conditional mapping to define the type of the person. So, we need to delete the “PersonalTypeID” from “Person” Entity. Then, we need to delete the whole “PersonType” Entity too! Here is the final model should look like:
If you are not using the “PeronalType” table to store the value, i.e. you are using integer or string, probably you may need to set the “Person” table to “Abstract”, otherwise you will get another annoying error:
Error 3023: Problem in Mapping Fragments starting at line xx,xx,xx : Column xxxx has no default value and is not nullable. A column value is required to store entity data.
Create object and Save to DB
You should now be able to compile without any error. In the following sample ASPX code, we have created “Student” object and assigned some properties to it. Note that we have NEVER specified the “PersonalTypeID”.
using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Transactions; using System.Data.Objects; namespace EntityTest { public partial class Test : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { SchoolEntities dataContext = new SchoolEntities(); using (TransactionScope transactionScope = new TransactionScope()) { Student student = new Student(); student.EnrollmentDate = DateTime.Today; student.FirstName = "John"; student.LastName = "Smith"; dataContext.People.AddObject(student); dataContext.SaveChanges(SaveOptions.AcceptAllChangesAfterSave); transactionScope.Complete(); dataContext.AcceptAllChanges(); } } } }
After running the above code, the “Student” is automatically saved with “PersonTypeID” assigned to “2″. It worked!
11×14 Spain and France Photos
After 5 years of having the Greece photos on the wall (from our wedding and honeymoon in 2006 – my first time of using a DSLR), Deb and I both feel that it’s time to have a change. We decided to replace them with a new Europe theme – Spain and France. With over 4000 photos from the 2 trips, I picked 6 of them which wasn’t an easy task. In Photoshop, I then tried to arrange them properly. To have ultimate balance, here is what I have chosen:
- 3 with very dark color (all indoor with strong shadow and highlight)
- 3 with bright color (all ourdoor, all HDR – 2 grass and 1 stone floor)
- 2 buildings – one facing left and one facing right
Next, I went to Costco Photo Center to develop 11″x14″ ($3.99 for 1 hour service), totally around $27 CAD with tax. The quality is pretty good!! It’s printed on Fuji photo paper with glossy finish, not bad.
Since the limitation is to select vertical photos, there were a lot of good photos cannot be used. Sigh! Compared to Greece photos back in 2006, I think my photography skills have improved a bit, right? Here are the best photos from both of the trips:
Japanese Maple leaves problem – turned brown
Problem: I have a 1 year old Japanese Maple which I planted last year, and this Spring (early summer) about 40-50 pieces of leaves started to turn brown. From the photos below, you can see there was no trace of insect bite and I could easily ruled out it was insect related. I looked up on the Internet and tried to find information about this. It almost came to a conclusion it was disease or fungus related, since I am no tree expert, all photos turning brown on Internet looked so similar to me.
Solution: I was about to go to local hardware store to pick up a bottle of Garden Fungicide, my friend told me he was going to a local nursery, so I bumped him a photo and asked him to show the nursery. When the lady at the nursery took a look, she said “It’s Leaf Scorch – it is due to improper watering techniques. You need to do deep watering to ensure roots have enough water. The idea is to trickle water for 15 min plus to let water seep to the lower layers”. The conclusion was that she didn’t think its a disease, but rather due to the hot weather/sun and lack of water at the roots.
Cause: I did more searching based on the “leaf scorch” keyword and found that her technique is actually the way to strengthen the root. Basically the idea is to avoid frequent light watering (just like treating lawn!!) and it should be periodically heavy watering to let the root develop better. Some articles also mentioned that the cause of the problem was actually due to clay soil and poor drainage. Part of the root system got rotten during last winter freeze, when the snow melted the clay didn’t drain the water fast enough and damaged the root. If it got stronger root, situation would have been better.
Of course, as usual I bumped into some products that captured my attention that could help solving this problem. So I bought 2 x deep drip water spikes from my all time favorite place, LeeValley. Does this fix the problem? It’s too early to tell, I will keep updating this article. Come back later for update.
- Deep Drip Watering Spike (LeeValley)
- Deep Drip Official Site
- Tree Root Feeder I.V (Saw this product online but didn’t buy)
DIY: Repairing the leaning fence post
Our fence is only 4-5 years old but because we hired some bad contractors that ruined the work, the fence started to lean badly away from my house. Please read my old article Fence Nightmere – Contractor drilled the hole and went away
There are a lot of articles and videos on Internet (even with specific repair products) to fix leaning fence post. Before fixing yours, you need to identify the problem because each case maybe different.
Don’t blindly follow what I did, my fix will ONLY work if:
- Your concrete base is still bonded perfectly to the wood
- The bottom of the fence post hasn’t rotten yet
- The direction of leaning – in my case, it’s leaning away from my house, so only ONE side of concrete is necessary and it saves a trip in ringing the door bell of my neighbor
Similar to my case, there is a video released from Home Depot:
How to Repair a Fence (@0:45 – 2:20) You can follow the video by using 2×4 and 1×1 to make the post level. However, I bought the Ground Anchor (Item#: 09A08.20) from LeeValley tools (one of my favorite places in Toronto) and I used them with the tie-down instead. It worked very well.
My addition: I was worried about the method provided by Home Depot wasn’t good enough because it was using the pure weight of the new concrete to secure the post. In order to secure the old concrete to the new concrete, I put 2 x Tapcon screws (see photos) into the old base. Then, I hammered 2 x 12″ galvanized steel nails into the clay soil at 45 degree, this helped securing everything.

















































































































































