Learning to love the Breville Oracle - Page 2

Need help with equipment usage or want to share your latest discovery?
Séb
Posts: 363
Joined: 10 years ago

#11: Post by Séb »

This morning i just find out that the steps for the grinders are too large for fine tuning espresso. I was at 17 and the volume was too low for my new coffee so i adjust it at 18 (coarser) and i got almost 15ml more! I do not have enought time to do more tests as i need to leave asap but tomorrow morning i will do a test at two settings and will measure and take pictures of the volumes i will get to be accurate. Once i will get back my Forte i think i will use the Forte AP to do my espresso and use the Oracle's grinders for the americano and latte. Will also see how the taste compare between my Forte and the Breville grinder.

So this look like a negative point if your goal is to get the absolute perfect espresso with this machine. But the espresso was quite good at my second setting but there could be situations where you just can't find the right settings.

angman
Posts: 160
Joined: 12 years ago

#12: Post by angman »

I have the Forte AP and the HG One handy. I'll play around some more but there is only so much coffee I can drink and dump in a day. I haven't found the steps to be too big on the Oracle yet though. Even on the Smart Grinder (newer model) it was OK.

Séb
Posts: 363
Joined: 10 years ago

#13: Post by Séb »

Ok, i had the time this morning to do some more tests. I did 8 tests in total, just trying different grinder setting, this is costly in coffee as i needed to purge between test and as far as i know there is no other way then to get a full dose to purge any remaining grind left. Also one thing that i have found is if you do not purge and do a back to back test with 17g instead of 18 for example, there will be very little change in the weight of the brew! But if you then do a second one there you see the effect of this grinder setting change which mean there is probably a fair amount of retention.

The stock portafilter is a double spout with a nice quality basket that looks very close in quality and finish to my VST. It looks like a 18g basket to me but the machine overdose it and it apply 30lbs of pressure when tamping. The PF weight 506g with the basket in place if you need that info. On the 8 tests that i did, i got one 21g dose, five 22g dose and two 23g dose. So we could conclude that the machine dose 22g +/- 1g. But i was playing a bit with the grinder setting but never more then two settings far apart.

My coffee is an espresso blend, freshly roast 4 days ago. So here is the results that i got this morning:

Grinder setting 17 = 23g dose yield 30g espresso at 28ml plus the crema for a 77% BR
Grinder setting 18 = 22g dose yield 44g espresso at 40ml plus the crema for 50% BR
Grinder setting 18 = 22g dose yield 47g espresso at 43ml plus crema for 47% BR

So you see that the difference is important and too big to me for just one step on the grinder adjustment (after a complete purge of a full 22g dose to be sure the change was effective). The last test again at 18g was just to check the accuracy/repeatability. I also did the same at the grinder setting 17 and it was always very close so it is fine for repeatability i think. I also did some tests at setting 16 but the volume was way too short for such a large 22g dose. That mean that for my actual coffee blend with his 4 days old age, i need to stay in the 17/18 grinder setting and i can fine tune the total time duration for the blonding point. With the 22g dose, the 18 grinder setting is ok right now for me.

Now the shot took a total of 38sec which include an 8 sec pre-infusion. The first drop happen at 10-11sec mark. I think that for a 22g triple dose theses settings are fine. I could play a little bit with the total duration and pre-infusion in order to get exactly what i want to maybe help compensate for the steps of the grinders.

Here are some pictures of shots taken yesterday and this morning so the volume does not necessarely fit my comments above, my comments are for the average shots i did with my testings but i did a LOT of tests/shots in two days! :

Shife
Posts: 552
Joined: 9 years ago

#14: Post by Shife »

4 days post roast is pretty fresh. That may be your issue. I'd try coffee that has a bit more time on it. You may be channeling shots due to how fresh the coffee is. Do you have a bottomless portafilter yet? I have a problem getting consistent shots using my Azykoyen with coffee that close to roast, and that's a 64mm flat.

I've been using an Oracle for several months and have not had any issues with step sizes. It does not use the same adjustment mechanism as the Smart. The steps are much much finer. If you find yourself at the extreme ends for the adjustments on the dial you can adjust the upper burr to get you back to a midpoint. I have my upper burr set 1 notch coarser than what it came from the factory at.

Retention is very low. Static is non-existent since the portafilter is directly connected while grinding. Mess is absolutely minimal. The cleaning brush that is supplied with the machine makes it very easy to clear out the chute. If the house burned down and I had to replace it, I'd buy one again. It's stupid simple to get amazing coffee while half asleep and changing a diaper. I would like a classic commercial single group lever, but this is a better fit for my life right now.

Shife
Posts: 552
Joined: 9 years ago

#15: Post by Shife »

FYI, the 15g VST basket fits perfect and will get you a 19-20g dose depending on tamp setting. The large holes in the 20g VST don't play well with the the auto tamper. The stock basket is dimensionally equivalent to the 18g VST

Séb
Posts: 363
Joined: 10 years ago

#16: Post by Séb »

Yes i know my coffee is too fresh, that is the problem when you are a coffee roaster :) Thanks for the tips about the burr adjustments. Good to know. I only have a VST20g and a 21g rancilio. But it is quite ok. One thing for sure, this is the ultimate machine for me wife as she can easily make herself a very good latte without my help :D

Séb
Posts: 363
Joined: 10 years ago

#17: Post by Séb »

Shife wrote:Do you have a bottomless portafilter yet?
No, i sold my previous naked PF and i am waiting my new one that will come with my Salvatore lever machine (a double PF, naked and double/triple basket too).

angman
Posts: 160
Joined: 12 years ago

#18: Post by angman »

I still don't have the 15 gram VST yet so using the stock and is overdosing. As for tamp pressure do you guys know which number = more pressure and which = less pressure? The manual doesn't actually say.

Séb
Posts: 363
Joined: 10 years ago

#19: Post by Séb »

angman wrote: As for tamp pressure do you guys know which number = more pressure and which = less pressure? The manual doesn't actually say.
The default setting equal 30 pounds and if you increase the number you increase the pressure, small numbers equals less pressure. Changing the tamp pressure will slightly affect also the dosing, up to 2g difference in dose. I did not yet play with this setting.

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nixter
Posts: 785
Joined: 16 years ago

#20: Post by nixter »

I sold my Giotto Evo late last year in favor of the Oracle and I'm very pleased. One little tip is that I've programmed the single shot button to be a 12sec purge. I use it to help bring everything to temp prior to pulled my first shot in the morning.