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Date: 04 Jan 2007 14:19:29
From: Thirsty
Subject: How to Finesse a Thermoblock??
I know you all love Silvias and hate thermoblocks. But here in New
Zealand, a Silvia + Rocky grinder costs ~$1500. Not everyone is
prepared to spend that much. Even second hand Gaggias and Saecos are
grossly overpriced. Whereas a thermoblocked Breville Cafe Roma costs
~$100 at an auction.

Furthermore, I am perplexed. Reviews in Consumer Magazine (NZ) and
Choice Magazine (Australia) for the last four years have rated the
thermoblocked cafe roma higher than the gaggia evolutions, the via
venezias etc. For machines <$600, the Cafe Roma has ruled supreme in
the last four tests.

One day I may be able to afford a Silvia or a Rocket, but not yet. So
my first machine is gonna be a thermoblocked Cafe Roma. Not as good as
a Rocket, but a small step up from the moka i currently use.

There are lots of thermoblock machines out there, but there is very
little technical info on them though. Has anyone ever tested a
thermoblock machine with a Scace thermofilter? Critics have sometimes
said that they tend to be too hot at the start of a shot and too cool
at the end of it. Is there any actual test data please?

As I understand it, a thermoblock forces water through a small gap with
an element in it to heat it up. They can quote pump pressures of
~15bar, but that is before the water is forced through a small gap.
Does anyone know what the actual pressure in the filter basket is for a
thermoblock machine please?

Have any hobbiests attempted to modify the circuit driving the small
element to improve temperture stability issues, if there are any. Are
there any ways to finesse the temperature of a thermoblock machines?
There is a certain hobbiest appeal in finesse an el cheapo machine to
produce better coffee.

It is easy enough for coffee snobs to criticise thermoblock machines. I
myself would have always thought that a boiler model would outperform a
thermoblock. I'm certain that is true for machines >$1000 but not so
true for <$500 level machines.

If the thermoblocks are so inferior, can someone please tell me why the
cafe roma and other thermoblocks have rated so well with the local
consumer magazines? The testers weren't mindless ninnys, they all
purported to be professional baristas. The cafe roma doesn't use a
crema enhancer gimmick either, so could its crema have in fact been
real?

How say ye??





 
Date: 14 Jan 2007 20:17:34
From: Thirsty
Subject: Re: How to Finesse a Thermoblock??
Ian Smith wrote:
> I don't see that there's anything to learn as such. It's the same as
> a boiler machine.
>
> Most of the cost is the PID unit itself. If you get a good deal of
> ebay, it will be cheaper.
>
> regards, Ian SMith

Thanks very much Ian, that's all been very helpful :-) .



 
Date: 10 Jan 2007 22:37:39
From: Thirsty
Subject: Re: How to Finesse a Thermoblock??

Ian Smith wrote:
> Yes, it's trivial. Just put a PID on the block.
>
> I had a PIDed Braun thermoblock for a couple of years. If you have a
> decent grinder, a PIDed thermoblock will give you better coffee than
> you get from most coffee shops. What it won't do is give you a second
> cup - you get one good shot, and then you need to give it quite a
> while to get up to temperature and get stable again.

An interesting suggestion.

I've heard of PID but don't know a whole lot about it. There are PID
kits out there but mainly for the Gaggias and rancilios - a digitally
controlled thermostat that fits onto the boiler I believe. How did you
learn to PID the thermoblock on your Braun?

I couldn't find any info on the net about fitting PIDs to thermoblocks.


Some of the PID kits look pretty deluxe. With a little electronics know
how, I imagine a barebones PID could be done cheaper?



  
Date: 11 Jan 2007 19:53:52
From: Ian Smith
Subject: Re: How to Finesse a Thermoblock??
On 10 Jan 2007 22:37:39 -0800, Thirsty <reznik101@hotmail.com > wrote:
>
> Ian Smith wrote:
> > Yes, it's trivial. Just put a PID on the block.
> >
> > I had a PIDed Braun thermoblock for a couple of years. If you have a
> > decent grinder, a PIDed thermoblock will give you better coffee than
> > you get from most coffee shops. What it won't do is give you a second
> > cup - you get one good shot, and then you need to give it quite a
> > while to get up to temperature and get stable again.
>
> An interesting suggestion.
>
> I've heard of PID but don't know a whole lot about it. There are PID
> kits out there but mainly for the Gaggias and rancilios - a digitally
> controlled thermostat that fits onto the boiler I believe. How did you
> learn to PID the thermoblock on your Braun?

I don't see that there's anything to learn as such. It's the same as
a boiler machine.

In a boiler machine you hook up a PID to keep the boiler metal at a
constant temperature. In a thermoblock you hook up the PID to keep
the block at a constant temperature.

> I couldn't find any info on the net about fitting PIDs to thermoblocks.

Buy a PID (ebay, 1/32 DIN, with a manual, SSR drive)

Buy a thermocouple (ebay or new)

Buy an appropriate SSR (ebay, mains voltage, 25A will eat it)

Unplug machine.

Open the machine.

Find the thermostat that is on the thermoblock, disconnect it, and
extend the leads to run to some space (possibly outside the machine)

Connect the leads to the SSR output

Find the mains switch, extend power leads from there to somewhere

Connect power leads to the PID

Connect thin wires from the PID output to the SSR input (observe
polarity)

Fix the thermocouple to the thermoblock. You can probably slacken
off the thermostat, poke the thermocouple underneath, tighten it up
again. I used special sticky tape.

Connect the end of the thermocouple wires to the PID. You can trim
them, don't extend them. Observe polarity.

Make sure all your connections are sound and safely isolated. Case
the PID and SSR (I put both in an earthed aluminium case fixed to the
side of the machine, case acts as heatsink for the SSR).

Plug in machine. Switch on. Configure PID as per manual.

> Some of the PID kits look pretty deluxe. With a little electronics know
> how, I imagine a barebones PID could be done cheaper?

Most of the cost is the PID unit itself. If you get a good deal of
ebay, it will be cheaper.

regards, Ian SMith
--


 
Date: 05 Jan 2007 14:18:05
From: daveb
Subject: Re: How to Finesse a Thermoblock??
Yeah, true somewhat.


NOT so good on stereo!! (understatement),

and they LOVE ALL things Toyota!

dave



Omniryx@gmail.com wrote:
> daveb wrote:
> > Go for it I say. get started and enjoy the trip.
> >
> > Dave
> > and to my knowledge in Norht America there is really only ONE consumer
> > magazine, period.
> > Consumer Reports.
> > they accept NO adverts, no bribes and BUY every single thing they test.
> > from cars to laundry soap.
> >
> > Dave
>
> Right on, Dave. I read their reports regularly.
>
> Unfortunately, they retain their historical
> crabby-little-old-lady-in-tennis-shoes mentality, meaning that their
> priy criteria are:
>
> Is it cheap?
> Will it run forever?
> How often do you have to repair it?
>
> As I recall, their recommendations about coffee were pretty scarey.



 
Date: 05 Jan 2007 11:29:53
From: Omniryx@gmail.com
Subject: Re: How to Finesse a Thermoblock??

daveb wrote:
> Go for it I say. get started and enjoy the trip.
>
> Dave
> and to my knowledge in Norht America there is really only ONE consumer
> magazine, period.
> Consumer Reports.
> they accept NO adverts, no bribes and BUY every single thing they test.
> from cars to laundry soap.
>
> Dave

Right on, Dave. I read their reports regularly.

Unfortunately, they retain their historical
crabby-little-old-lady-in-tennis-shoes mentality, meaning that their
priy criteria are:

Is it cheap?
Will it run forever?
How often do you have to repair it?

As I recall, their recommendations about coffee were pretty scarey.



  
Date: 05 Jan 2007 22:04:49
From: Jack Denver
Subject: Re: How to Finesse a Thermoblock??
Likewise their taste in audio equipment, cars, just about everything except
washing machines (where their usual priorities actually make some sense).



<Omniryx@gmail.com > wrote in message
news:1168025393.897936.123170@i15g2000cwa.googlegroups.com...
>
> daveb wrote:
>> Go for it I say. get started and enjoy the trip.
>>
>> Dave
>> and to my knowledge in Norht America there is really only ONE consumer
>> magazine, period.
>> Consumer Reports.
>> they accept NO adverts, no bribes and BUY every single thing they test.
>> from cars to laundry soap.
>>
>> Dave
>
> Right on, Dave. I read their reports regularly.
>
> Unfortunately, they retain their historical
> crabby-little-old-lady-in-tennis-shoes mentality, meaning that their
> priy criteria are:
>
> Is it cheap?
> Will it run forever?
> How often do you have to repair it?
>
> As I recall, their recommendations about coffee were pretty scarey.
>




   
Date: 06 Jan 2007 03:45:56
From: Barry Jarrett
Subject: Re: How to Finesse a Thermoblock??
On Fri, 5 Jan 2007 22:04:49 -0500, "Jack Denver"
<nunuvyer@netscape.net > wrote:

>Likewise their taste in audio equipment, cars, just about everything except
>washing machines (where their usual priorities actually make some sense).
>
>

hmmm, cars, too. maybe.


--barry "314,000 on a toyota"



 
Date: 05 Jan 2007 08:27:19
From: daveb
Subject: Re: How to Finesse a Thermoblock??
Go for it I say. get started and enjoy the trip.

Dave
and to my knowledge in Norht America there is really only ONE consumer
magazine, period.
Consumer Reports.
they accept NO adverts, no bribes and BUY every single thing they test.
from cars to laundry soap.

Dave



 
Date: 05 Jan 2007 09:50:48
From: Jack Denver
Subject: Re: How to Finesse a Thermoblock??
While good thermoblock machines are theoretically possible, in practice they
all seem to be cheaply built. I doubt you'll find many serious hobbyists
(the kind that own Scace thermofilters) messing around with these toys for
the same reason that not many Yugos get hot-rodded.


As for why consumer magazines are so wildly off in their ratings, usually
this comes from an improper weighting system in the rating scale. Even if
they get pros to do the taste tests, the editors designed the scoring
system and if you read the fine print they weight things like ease of use
that have nothing to do with taste quite heavily and may even lead to
perverted results where the very things that make the machine a poor choice
for serious coffee drinkers (e.g. a lightweight grouphead) get the machine
extra points for "rapid warm up".

Not to be self serving but I think you'll get a lot better advice about
espresso machines here than you will from a magazine that is clueless about
espresso - last week they were testing dishwashers, next week it will be
stereo speakers - they are jacks of all trades, masters of none. If I
wanted to know what laundry detergent is best, this group might not be the
best place to ask (Tide with bleach alternative, actually) but for coffee
advice I think the degree of expertise here is unparalleled.





"Thirsty" <reznik101@hotmail.com > wrote in message
news:1167949169.536174.307760@q40g2000cwq.googlegroups.com...
.
>
> Furthermore, I am perplexed. Reviews in Consumer Magazine (NZ) and
> Choice Magazine (Australia) for the last four years have rated the
> thermoblocked cafe roma higher than the gaggia evolutions, the via
> venezias etc. For machines <$600, the Cafe Roma has ruled supreme in
> the last four tests.
>
> One day I may be able to afford a Silvia or a Rocket, but not yet. So
> my first machine is gonna be a thermoblocked Cafe Roma. Not as good as
> a Rocket, but a small step up from the moka i currently use.
>
> There are lots of thermoblock machines out there, but there is very
> little technical info on them though. Has anyone ever tested a
> thermoblock machine with a Scace thermofilter? Critics have sometimes
> said that they tend to be too hot at the start of a shot and too cool
> at the end of it. Is there any actual test data please?
>
> As I understand it, a thermoblock forces water through a small gap with
> an element in it to heat it up. They can quote pump pressures of
> ~15bar, but that is before the water is forced through a small gap.
> Does anyone know what the actual pressure in the filter basket is for a
> thermoblock machine please?
>
> Have any hobbiests attempted to modify the circuit driving the small
> element to improve temperture stability issues, if there are any. Are
> there any ways to finesse the temperature of a thermoblock machines?
> There is a certain hobbiest appeal in finesse an el cheapo machine to
> produce better coffee.
>
> It is easy enough for coffee snobs to criticise thermoblock machines. I
> myself would have always thought that a boiler model would outperform a
> thermoblock. I'm certain that is true for machines >$1000 but not so
> true for <$500 level machines.
>
> If the thermoblocks are so inferior, can someone please tell me why the
> cafe roma and other thermoblocks have rated so well with the local
> consumer magazines? The testers weren't mindless ninnys, they all
> purported to be professional baristas. The cafe roma doesn't use a
> crema enhancer gimmick either, so could its crema have in fact been
> real?
>
> How say ye??
>




 
Date: 05 Jan 2007 14:02:44
From: Ian Smith
Subject: Re: How to Finesse a Thermoblock??
On 4 Jan 2007 14:19:29 -0800, Thirsty <reznik101@hotmail.com > wrote:

> Have any hobbiests attempted to modify the circuit driving the small
> element to improve temperture stability issues, if there are any. Are
> there any ways to finesse the temperature of a thermoblock machines?
> There is a certain hobbiest appeal in finesse an el cheapo machine to
> produce better coffee.

Yes, it's trivial. Just put a PID on the block.

I had a PIDed Braun thermoblock for a couple of years. If you have a
decent grinder, a PIDed thermoblock will give you better coffee than
you get from most coffee shops. What it won't do is give you a second
cup - you get one good shot, and then you need to give it quite a
while to get up to temperature and get stable again.

If you only want one cup an hour (say), my experience was that a PIDed
thermoblock averaged at least as good coffee as a stock Silvia that
wasn't surfed in some way. The thermoblcak is consistently OK, a
Silvia that isn't nursed a little is somewhat variable.

regards, Ian SMith
--


 
Date: 04 Jan 2007 21:22:43
From: aanon
Subject: Re: How to Finesse a Thermoblock??
Hi Thirsty,

I owned a Cafe Roma for a brief period when I started getting into
coffee. I was influenced by the Choice reviews and so on at the time.
Plus the $99 price tag (on sale at Dick Smith) made it an easy buy.

Since then I've had a Carezza and then a Mininova, and I now drink
vacuum at home and do lots of tasting of espressos through a commercial
HX at work. I only point these things out in order to say that I may be
more fussy these days if i went back to try the Cafe Roma again.

That said, I thought the Cafe Roma made quite decent coffee. It was
good enough to make me want to get fresher and better beans and try out
roasting my own. Not every shot was good, of course, but when the shot
timing and volume were good, and when everything was hot, the result
was ok and sometimes good. Cappas were ok, and getting microfoam was
pretty easy because steaming was really slow and there is a simple
single hole steam tip. Again, this might drive me mad if i went back to
it now, but it was definitely useable.

I don't know much about finessing the thermoblocks, I guess getting a
cheap multimeter and thermocouple and trying a few experiments for
yourself is the way to go. You can switch to steam for a while if you
need to bump up the temperature, etc.

Just a couple of technical things: the basket is actually a dual wall
crema enhancing thingo. I never tried modifying this but perhaps you
could. The portafilter is very light, terrible at holding heat,
terrible at holding the basket in, and needs a few plastic bits removed
if i remember correctly. Also remove the 'froth enhancing' sleeve. When
steaming milk, surf the surface of the milk the whole time and try to
get it spinning in the jug - there will be no separate 'stretch' and
'incorporate' stages when steaming with the Cafe Roma.

If you're just keen about coffee and not dead-set on espressos/cappas
etc, your strike rate for tasty coffees will almost certainly be better
with a vacuum brewer or french press. Just a thought.

Good luck,

Aanon



  
Date: 05 Jan 2007 06:37:16
From: Coffee for Connoisseurs
Subject: Re: How to Finesse a Thermoblock??
1) Buy the best grinder you can afford (see
http://www.coffeeco.com.au/articles/september2002.html . I imagine it will
translate almost 100% to NZ.)

2) See (1).

3) The Roma has pressurized, undersized pf baskets; use the double all the
time.



--
Alan

alanfrew@coffeeco.com.au
www.coffeeco.com.au




 
Date: 04 Jan 2007 21:17:43
From: Thirsty
Subject: Re: How to Finesse a Thermoblock??

abimer wrote:

> if you read the consumer magazine's reviews of grinders, you will find
> that grinders from the likes of farmers or noel leemings just don't cut
> it for espresso. normally, you will still need to spend a couple
> hundred on a second hand grinder.
>
> that said, reputably, the petra grinders that are from time to time
> available on trademe for $50-$100 are okay for espresso, so you never
> know...

I agree about the grinder. Have a hand wound coffee mill at moment.
Planning to upgrade to Delonghi KG-100, which I believe is basically a
Solis Scala 166.

The Breville is a compromise, cheap enough that I can easily cast it
aside later when I want to invest more seriously down the track.



 
Date: 04 Jan 2007 16:43:47
From: abimer
Subject: Re: How to Finesse a Thermoblock??
Hi Thirsty,

I have tasted some quite good espresso from thermoblocks like the cafe
roma and the other breville one (800 series?) it is not syrupy like
espresso from a grander machine, but tasty all the same. The brevilles
are quite consistent and a good start to home espresso in the right
hands.

my first machine was a krups thermoblock, and with a little patience, i
was able to get a routine that meant i got quite consistent results
temperature-wise. i don't think temperature is a problem with such
machines.

however, if you or someone close to you drinks flat whites or
cappucino, however, these machines lack power for steaming milk, in my
experience doing a very inadequate job in that department.

I have never seen the nz consumer magazine report you mention. in the
past, the reports i've seen have only included machines from the likes
of breville, sunbeam and delonghi. most people here who have used
gaggias have been pleased with them. apart from using a boiler rather
than a thermoblock, they use quality components in the group with high
thermal mass for good temperature stability. the same cannot be said
for the brevilles. again, this is not to say that the likes of the
breville cannot produce good espresso.

even if you're happy to go as cheap as possible with the machine,
there's still the matter of the grinder. the most common advice you
will find on this newsgroup is that if you're on a budget, spend less
on the machine and more on the grinder.

if you read the consumer magazine's reviews of grinders, you will find
that grinders from the likes of farmers or noel leemings just don't cut
it for espresso. normally, you will still need to spend a couple
hundred on a second hand grinder.

that said, reputably, the petra grinders that are from time to time
available on trademe for $50-$100 are okay for espresso, so you never
know...

good luck!

Paul.



  
Date: 05 Jan 2007 18:31:48
From: Natalie Drest
Subject: Re: How to Finesse a Thermoblock??

"abimer" <paumcb12@gmail.com > wrote in message
news:1167957827.703859.289680@38g2000cwa.googlegroups.com...
> Hi Thirsty,
most people here who have used
> gaggias have been pleased with them.

I sure am. Buy an Evolution from Ebay Australia, & have it sent over. Don't
pay over $80AU. It'll outlast 10 Brevilles.

apart from using a boiler rather
> than a thermoblock, they use quality components in the group with high
> thermal mass for good temperature stability. the same cannot be said
> for the brevilles. again, this is not to say that the likes of the
> breville cannot produce good espresso.

Okay, I'll say it.
The Breville can't produce good espresso- not even the 800 series.
They have plastic collars on the group head instead of brass, preventing
proper heat transfer to the group handle, so even if the water temp remains
relatively stable, as soon as it hits the cold group handle, the temp drops
off.

>
> even if you're happy to go as cheap as possible with the machine,
> there's still the matter of the grinder. the most common advice you
> will find on this newsgroup is that if you're on a budget, spend less
> on the machine and more on the grinder.
>
> if you read the consumer magazine's reviews of grinders, you will find
> that grinders from the likes of farmers or noel leemings just don't cut
> it for espresso. normally, you will still need to spend a couple
> hundred on a second hand grinder.

How much are the Sunbeam grinders over there? The EM 480 can be had for $160
in Au, and they have just released a cheaper one (same burr set, cheaper
body) that would be a sensational buy. Same burr set as the Lux.




 
Date: 04 Jan 2007 15:13:39
From: razmoo
Subject: Re: How to Finesse a Thermoblock??
ah sorry not to flood, but I thought the Breville Cafe Roma was like a
~$400 machine, if you can get it for $100 go for it.



 
Date: 04 Jan 2007 14:50:56
From: razmoo
Subject: Re: How to Finesse a Thermoblock??
I think you can get a new silvia for about AU$700 AU on ebay.. Id
rather pay a extra couple hundred for one thats for sure. And if you do
get the cafe roma you still are going to need a good grinder and that
will cost AU$200+ (probaby $400 for the rocky)



 
Date: 04 Jan 2007 14:47:54
From: razmoo
Subject: Re: How to Finesse a Thermoblock??
Hi there, I've got a siliva and rocky from Ebay Australia for about
$1200 including shipping. Came with the base which is supposidly worth
$150 or so but I don't particularly like it. So you could probably get
the combo on there cheaper than retail without the base.

Anyways.. I have no idea what a cafe roma is like but here is a review
of the sunbeam dual thermoblock
http://www.coffeeco.com.au/articles/sunbeam.html - i think the review
is quite good.