Nuova Simonelli Oscar - First Impressions and Tips

Need help with equipment usage or want to share your latest discovery?
cianocian
Posts: 2
Joined: 9 years ago

#1: Post by cianocian »

After months of searching and evaluating machines through internet reviews I took the plunge and purchased a Nuova Simonelli Oscar. I started out with a Delonghi EC155 which I used for approx. 1 year. I modified the Delonghi as much as I could to try and control brew temperature and quickly got annoyed with how long it took me to brew a few milk drinks for guests. The huge temperature variation from shot-to-shot was also a real pain and I git bored of the average espresso produced by that machine. I have the pleasure to enjoy great espresso from the multitude of great coffee shops in Toronto so I wanted to upgrade to something far better and be able to produce multiple milk drinks without taking taking forever!

I wanted a reasonably-priced machine that was still capable of producing quality espresso. So far the Oscar produces great shots as long as I have my tamping and grind set properly. It took me a while to get used to how quickly the Oscar steams, but, I now find it easy to produce microfoam using the 4-hole tip. The steam power - I love it! I have read many complaints about the 4-hole tip, but, I have seen many baristas use a 4-hole tips so I just watched what they do and ask questions. I find I'm in the ballpark with foaming milk, but, I have to keep practicing my latte art skills. Actually, at this point my skills can be equated to luck and not much else. I think one just needs to practice with this machine to get good foaming results. It tales around 20-30 seconds to get the milk up to temp, but, that's a plus, why would you want to wait so long?

I have read several reviews and tips on how to mod the Oscar. So far I am tempted to install the gigleurs to improve temperature stability, but, given the results I am getting with my current setup I'm not sure I need it. Using a Baratza Virtuoso grinder and Pilot Big Bro beans I am capable of a decent ristretto that is reasonably sweet without much sourness and definitely no bitterness. That said, maybe the shots would be even better with the gigleurs! I have only seen channeling when I try to correct a tamp by re-tamping. I also find the portafilter to be quite forgiving.

I also wanted to pass along a tip I read in one post ( I forget where I read it!) in regards to using a timer. It is usually recommended to install an anti-vac valve on the Oscar if you want to use a timer. The tip I read suggested to open the steam valve one full turn to release the air when the boiler is heating up. I tested this and found no steam comes out after one full turn so I then plugged in the Oscar to a timer. For two weeks I have found the Oscar is fully up to temperature when I get up in the morning. I have the timer set to be on for about an hour before I get up. By the time I get up and I can feel the portafilter is piping hot and the steam pressure is also at full power. I feel this is a simple and effective workaround to the Oscar anti-vac issue. I have also been informed that anti-vac valves can also stick so sooner or later you will run into to a false pressure situation regardless.

Finally, this is a comment/question regarding installing an over pressure valve. If you have your grind/temp correct do you really need an over pressure valve? My understanding is that you should get 9-10 bar based on flow rate which is determined by tamp and grind. I could see that a coffee shop would want to have more consistency in espresso shots whilst pulling shot after shot. Sooner or later som parameter may be incorrect so you still want to be able to pull a decent shot so an OPV can help in this regard. In such cases I don't believe you will produce a fantastic shot since tamp and/or grind is out.

All-in-all I think the OScar is a great machine and it is priced a lot cheaper than most other machines that in the HX category. It may be a little more difficult to use unmodified, but, that's what the barista is for!

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JmanEspresso
Posts: 1462
Joined: 15 years ago

#2: Post by JmanEspresso »

The Oscar IS a nice little machine, perhaps a little outdated compared to other options on the market, but certainly a solid little beast.

IN regards to using a programmable timer so the machine is hot and ready to go when you wake up... Oscars often dont come with a Vaccum Breaker valve on the steam boiler. Perhaps the new oscars DO have a vac breaker installed, Im not sure. Sounds like yours has one, whether someone added one, or it came with one, IDK. When the steam boiler is heating up from cold, it builds up pressure on its way to 212F/Boiling. IF there is no vacuum breaker, the pressurestat which controls the pressure(and therefore temp) of the boiler, is fooled into thinking the machine is up to temp. So normally, you would leave the steam knob open while the machine is heating up, wait for it to start to sputter and spit out some steam, close it, and now the machine can heat up to its proper temp, which is somewhere between 240-260F.

IF you walk up to your machine after its been on for 40 minutes, and you open the steam knob and get plenty of steam pressure, and the machine is all hot and nice, and you get flash boiling water coming from the grouphead for a few seconds, then I would say YES, your machine has a vacuum breaker valve.

There you go, one of the biggest complaints about the Oscar, and you dont have to deal with it.

Im not familair with Pilot Coffee Roasters, but from the looks of their website, they're a proper roaster(Actually the offerings look great IMO). The Baratza Virtuoso is definitely what is going to hold you back from consistently producing a good shot, but its workable. I would definitely suggest getting into real espresso grinder as soon as your budget allows.

And lastly about the over pressure valve. So your asking, if you have the grind and dose correct for a proper extraction, shouldnt the pump give you the approximately 9bars of pressure. Yes and No. There ARE machines that dont have OPV valves to adjust pump pressure, and people like them. IIRC, the excellent and elegant Elektra Semi Automatica, lacks an OPV valve. Ideally, especially for my personal position, the machine should have one. You should be allowed to explore the entire extraction space of espresso, and have the pump be a nuetral contribution to the process, rather that having to needle tip your extraction into a much smaller extraction window so the pump operates properly. If you want to try and pull some some flowing, updosed ristretto shots, you could pulling as high as 12, 13 bar. Furthermore, if you want to pull some exceptionally quick, brisk shots, you could pulling below that 9bar window, but otherwise could still be inside the accepted extraction space. Its not just about saving shots that are completely otherwise out of whack(as you state, to have consistency in a commercial environment). For example, if the grind and dose are such that you're going to end up with a 3-4oz in 20 seconds, the pump isn't going to get up to pressure regardless of an OPV valve or not. There needs to be that level of resistance for the pump to get up to pressure. And then on the other hand, as I said with the tighter, updosed ristretto style shots, without an OPV, the higher resistance is going to drive the pump pressure up too high, whereas WITH an OPV valve, the pump will just put out that 9Bar(or whatever you're set too). The OPV Valve serves to bleed off any excess pressure the pump produces, so if your grind and dose would otherwise produce 12bars, the OPV bleeds off a proper amount of water, so what arrives at the group, is your set pressure of somewhere around 9bar.

Personal opinion, would be to see what is required to add an OPV valve to the machine so you can properly adjust pump pressure. Can you make good espresso without one? Yes. Would it be easier and allow more flexibility to explore the extraction space if you had one? Yes.

cianocian (original poster)
Posts: 2
Joined: 9 years ago

#3: Post by cianocian (original poster) »

JManEspresso thanks very much for the tips and comments. I don't think a have a vacuum breaker, I leave the steam valve partially open( 1 full turn), just enough to release the air, but, I don't end up with a sauna in my kitchen. I think it's an acceptable workaround.

In regards to a grinder, what would you suggest that would complement the Oscar? That is, an espresso grinder that will improve the quality of my shots, but, is not out of the Oscar league so I'm not spending too much. I seem to prefer conical burrs for grinders if that would narrow down the possibilities .

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bluesman
Posts: 1594
Joined: 10 years ago

#4: Post by bluesman »

cianocian wrote:I leave the steam valve partially open( 1 full turn), just enough to release the air.
Unless you hear air escaping and you close it when that happens, one turn may not be enough. I can feel a slight increase in resistance as mine reaches the opening point, and it occurs at about one full turn on the new valve I just installed. It took about 1 1/2 turns on the original one. If you can leave the knob where you set it until the boiler's heater light goes out and no steam or water comes out, it's not open at all.

The sector of rotation between closed and fully open is very narrow (about 45 degrees) & it's somewhere near the middle of the knob's full rotation. You shouldn't turn the valve fully in either direction - just open it until you're getting full steam and close it only enough to turn the steam fully off. By using only the "active" part of the knob's range, you can focus better on foaming and the O-rings on the shaft of the valve will last a lot longer.

mbawez1
Posts: 1
Joined: 9 years ago

#5: Post by mbawez1 »

First post here,
I have an Oscar that used to be an Illy/oscar machine, I removed all the added hardware to the grouphead and installed the required diffuser, gasket,screen and the retaining screw, so now it is a normal looking and functioning Oscar.
It does have the vacuum breaker valve it is very easy to see when you open the top " 6 phillips screws" right next to the boiler water level probe sensor.
It also has a programmable dispense timer and infusion option. I have read in the marketing brochure that the machine is set to produce 9 bar at the brew head, I have not measured it and am in the process of getting the gauge to do that. I must confess that I have fooled with the prusserstat once and I may have altered the sittings and I don't know exactly the boiler steam pressure value. I am in the process of getting the right tools "gauges and fitting to set it back to the 1.2 bar value if it is off. I am about to get a naked portafilter.
I am still new at this, there is a lot to be learnt in the art for producing a good espresso shot.
Now that may first post is over I feel a whole a lot better.

cheers