HomeRoast Digest


Topic: Best Grinder for Coarser Grinds (39 msgs / 1200 lines)
1) From: Ron West
I recently bought a Cona glass filter for my Yama 8-cup, and I am now having
problems with draw down times.  I read the recent thread in this list,
regarding draw down times and the quality of the grind, so I am at least
prep'd to understand the issue.  Before this I have been using the cloth
filter that came with the Yama, and already I am starting to wonder if the
glass rod is worth it.
 
My draw down times exceed 10 minutes with the coarsest grind I have.  Even
with 10 minutes plus it usually stalls completely at several points, and I
have to wiggle the rod, as it suggests on Sweet Maria's site.  That always
allows some grinds to reach the bottom carafe, so it seems I might as well
be using my French press.
 
I have searched for reviews on what is the best grinder for the coarser
grinds, and my grinder is often recommended: the Capresso Infinity.  Can I
get your recommendations on which grinder you feel produces the best quality
grind for the VacPot or French press?
 
Thanks to everyone who contributes to this list, it has been a great source
of information for this neophyte.
 
Ron West
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2) From: Doug Hoople
Hi Ron,
If I'm not mistaken, the Capresso Infinity is a conical-burr grinder. The
rap on conical-burr grinders is that they're wildly inconsistent in the
coarser ginds. And it appears to be true. The SM website mentions this in
discussing the Zass hand mills. And I've experienced it personally on the
Barazta Virtuoso I've had for a month or two now.
If this is true, then even the Mazzer Robur should have trouble with this.
The Robur gets pointed by its owners almost exclusively at espresso grinds,
so I'd be willing to bet that we have no data points anywhere on this. But
it would certainly be interesting to try a Robur in a coarse grinding
experiment.
This problem also manifests itself more in darker roasts than lighter
roasts, and Tom has weighed in here with his observations about how brittle
and easily-shattered the darker roasted beans can be. I know that I
consistently have trouble at darker roasts than lighter roasts, and, in
fact, have perfectly reasonable drawdowns from City-roasted beans at a
grinder setting that is guaranteed to produce a stall with a French roast.
So I'm burying the big story way down here at the end of this... I've ground
my problem French roast on the Virutuoso very fine, and gotten 30-second
drawdowns on it!!!!!
That's right. With a conical-burr grinder, the finer you grind, the better
your results in the drawdown. I've discovered that I get slow-but-reasonable
drawdowns at 20 (out of 40, with 40 being the coarsest), better drawdowns at
15, reliable and consistent drawdowns at 10. But the real surprise was the
lightning-fast drawdown at 2!!
Going coarser, anything higher than 20 invites problem drawdowns, and
anything higher than 30 invites stalls.
So the conical-burr grinders really do excel at finer grinds, and the finer
you go, the better they get. Which is exactly wrong for coarse grinds.
I'm hoping in the near future to get my hands on a flat-burr grinder so that
I can see how much difference the grinder will make in the coarser settings.
I've been led to believe that it will be substantially better, but I've also
found that this is largely unexplored territory and that most of the advice
is supposition inferred from the espresso ranks (which doesn't count) and
from not direct experience.
So try the fine range on your Infinity, and see if your results don't
improve. Your coffee will taste more like French press, but you'll have
controlled drawdowns. Once you find your range of 'better' behavior, you can
start tweaking back toward coarse until you hit the inflection point where
your drawdowns start acting up again.
One final note... the Cona rod is a pretty poor match for the Yama 8-cup. In
fact, all the matches I have (Cona, Corning, Cory) are not so great, with
the Cory being the best of the lot. The Cory has the deepest texturing of
the trio that I have, although they're all different.
One really final note... I'm of the opinion that, in order for vacpot coffee
to reach its potential height of distinctiveness, meaning for the sweetest
and cleanest cup, a coarse grind is neccessary. The finer grinds do tend to
be muddier, and harder to distinguish from press. I still don't have a lot
of experience to back this up, but the successes I've had in the middle of
my experimenting have all pointed in this direction.
So the jury's still out on the best grinder for coarse grinding.
Let us know how you make out!
Doug
On Mon, May 11, 2009 at 7:01 AM, Ron West  wrote:
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3) From: miKe mcKoffee
The Bunn G series grinders do a very good job on coarse grinds, takes about
30sec to grind an LB for press. Wait, they're kind of huge and bulky, and
somewhat spendy. Ok, back down to home use zone and my real post:-)
Question: how many pounds have been run through your Infinity since last (if
ever) burr replacement? As burrs wear they create more and more and more
fines from pulverizing rather than cutting the beans... A grinder like Rocky
is good for about 75# espresso, likely 200 or so if all press coarseness. A
lower end grinder like Maestro/Infinity class much less.
Slave to the Bean Kona Konnaisseur miKe mcKoffeehttp://www.mckoffee.com/Ultimately the quest for Koffee Nirvana is a solitary path. To know I must">http://www.NorwestCoffee.comURL to Rosto mods, FrankenFormer, some recipes etc:http://www.mckoffee.com/Ultimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.
Pacific Northwest Gathering VIIhttp://themeyers.org/HomeRoast/">http://home.comcast.net/~mckona/PNWGVII.htmSweet Maria's List - Searchable Archiveshttp://themeyers.org/HomeRoast/
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4) From: Ron West
My Infinity was new for Christmas.  It has had probably 25 lb run through
it, from medium to coarse.  It has not had the burrs replaced.
I was considering a grinder upgrade, and was looking at the Rocky.  However,
I was stopped by descriptions of the Rocky doing a 'passable' job of the
coarser grinds.  Would you say this is a fair assessment, or would it do a
better job than my Infinity with a Vacpot grind?
Ron

5) From: Doug Hoople
"As burrs wear they create more and more and more fines from pulverizing
rather than cutting the beans..."
Hi MiKe,
With conicals, it doesn't matter whether they're new or old. The coarse
settings will be inconsistent in the best of cases.
Doug
On Mon, May 11, 2009 at 8:07 PM, miKe mcKoffee  wrote:
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6) From: John Borella
 . I grind a little finer then drip on my Super Jolly & get sweet, clean 
brews in my Harios using a cloth filter. If you want a grinder that does a 
nice job on coarse grinds pick up a KitchenAid Pro flat burr grinder. I use 
mine for french press & Toddy brewing and really like it in that grind 
range.

7) From: Doug Hoople
Well, the hypothesis is that flat burrs will do a better job, so any decent
flat-burr grinder should surpass even a Robur in the coarser range. That is,
if the theory holds.
There's still very little actual data, as glass-rod vacpot appears to be the
only application where this is critical, and glass-rod vacpot is still a
pretty esoteric domain.
Dark-roast in a glass-rod vacpot is more esoteric still, and constitutes the
ultimate test for coarse grinding.
The caveat to all these observations is that, unlike with espresso, where
there are miles and miles of data and reports, and lots of practitioners,
there really aren't a lot of glass-rod vacpotters, and fewer still who like
their roasts dark.
If you do decide to spring for another grinder, make sure you post your
results here.
Thanks.
Doug
On Mon, May 11, 2009 at 8:54 PM, Ron West  wrote:
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8) From: Doug Hoople
One other thing. How dark are your roasts?
If you don't habitually brew with dark-roast coffee, then your drawdowns
shouldn't be a problem.
Before you invest in another grinder, you might want to consider a different
glass rod. All the rods are different, and some mate better with the Yama
8-cup than others.
If you're brewing dark roast, then you'll have trouble with any rod. If
you're brewing with lighter roasts and still having a problem, then it would
pay to trouble-shoot the glass rod first.
Doug
On Tue, May 12, 2009 at 9:22 PM, Doug Hoople  wrote:
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9) From: Ron West
Well, I generally do not brew dark roasts.  This bean I am using to
experiment with the Vacpot is a melange of C+ and FC+ of Kenya Auction Lot
#786 Rukira.  And still, I was getting the 10 min plus drawdown times I
mentioned.
Latest developments.  I borrowed my son's Kitchenaid Pro flat burr grinder.
It gets a much more consistent coarse range.  Just playing with it this
morning, I got a (still somewhat slow) 7 min drawdown.  But the cup quality
is much better!  So I'm beginning to see a light at the end of the tunnel.
It is coming down to grind consistency, as I suspected it would.
Ron

10) From: Doug Hoople
" I grind a little finer then drip on my Super Jolly & get sweet, clean
brews in my Harios using a cloth filter."
Hi John,
The range from press to drip is in the 20s on the Vario, and anything above
around 18 or so is problematic. The times that I haven't had drawdown
problems in that range (sometimes, you just get lucky) have yielded, as you
say, "sweet, clean brews."
You've got two things that make things work for you, maybe even three...
1) Cloth filters. Whatever your grind, however dark your roast, you'll never
have drawdown problems with the cloth filters.
2) The Super Jolly is one of the best-rated flat-burr grinders out there,
and probably actually wins in a walk against the Robur or the Kony for this
particular task..
3) The maybe part... if you're drinking roasts that are FC or lighter.  I
don't know how dark you roast, which is why this is a maybe.
1) and 3) will, each by itself, prevent problem drawdowns.
With the glass rod, I'll be really interested in finding out if 2) (a
high-quality flat-burr grinder) will make a difference.
I'm still drawn to the glass rod, for all the grief it's given me. When it's
actually working, you can't improve on the coffee it makes.
Doug
On Tue, May 12, 2009 at 6:42 PM, John Borella wrote:
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11) From: Ron West
Truth be told, I get a very nice cup in the vacpot, using the cloth filter.
But I am always trying to find ways to brew that perfect cup of coffee.
Much of what I have read on this list has underscored the importance of a
good consistent grind.  But even with a grind that I now know is anything
but consistent, the cloth filter has given me a fairly consistent brew,
never slowing drastically, never stalling.  If I can overcome the obstacles
of the glass rod filter, my reward just might be a fantastic cup of coffee.
I guess I bought the glass drainer as much for testing my grind as anything.
Ron

12) From: Doug Hoople
"The range from press to drip is in the 20s on the Vario,"
My apologies!!!! I meant the Virtuoso. The Virtuoso, because it's a
conical-burr grinder, is the what becomes problematic above 18 (40 being
coarsest).
I think the reason I mistakenly substituted Vario (which is a flat-burr
grinder) is that I've got Vario on the brain. I'm in the final stages of
upgrade fever, and am really close to pulling the trigger on a Vario as a
potential solution to the problem.
Thus, it's almost criminal to implicate it in the problem that it's actually
supposed to solve!!!
Doug
On Wed, May 13, 2009 at 7:32 AM, Doug Hoople  wrote:
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13) From: Doug Hoople
Hey Ron,
Nice going getting your hands on a flat-burr grinder. You've gone a major
step in establishing that flat burrs are recommended for going coarse.
7 minutes is still long, but it's a definite improvement on 10 minutes. I
consider 10 minutes a hard stall.
FC+ is the crossover where things start getting delicate, so that may be
part of it.
But if you've still got the patience (I just read your next post about the
glass rod being more for testing than for daily use), you might want to see
if you can get one of the older, used glass rods, with the deeper texturing
at the mating surface.
That might get you down from 7 minutes to more consistent times. 7 minutes
is still long, and if that's the average, you'll still find yourself
getting hard stalls occasionally.
With a different glass rod, you might be able to get the average below 3
minutes. You might get lucky, and even get downright normal drawdown times
(1:30).
Keep us posted!
Thanks.
Doug
On Wed, May 13, 2009 at 6:51 AM, Ron West  wrote:
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14) From: Jeff Kilpatrick
Ron-
I've been using a vacpot with both spring-loaded and glass rod filters of
many kinds and five different grinders (one whirly blade and four conical
burr mills of vastly varying quality for a few years.  Throughout the range
of grind, I've never gotten drawdown times over 3 minutes with anything but
the plastic filter that ships with the Santos unless I was doing something
funny.  I'm sure you've thought of this but just to be sure: are you letting
the water "boil" into the top for a minute or so?  If you just send the
water north and then immediately take it off the heat, vacuum never gets a
chance to set up so you'll stall all the time.
Good luck!
-jeff
On Wed, May 13, 2009 at 2:19 PM, Doug Hoople  wrote:
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15) From: Doug Hoople
Hi Jeff,
What's the darkest roast you've brewed with the glass rod? How often do you
use the glass rod filter relative to the spring-loaded filter (which I
assume is cloth-covered)? And how coarse/fine are your grinds?
Actually, come to think of it, what pot and glass rod combination do you
use? Santos/Cona? Something else?
If you're only brewing light roasts (FC and lighter), then you probably
won't have any problems. At all. At any grind.
If you're grinding relatively fine with the conical burr mills, then you'll
do better than if you grind coarse, and that might prevent you from having
experienced this problem.
It's also possible that the pot you're using has a mating surface with the
glass rod that's better suited than the typical combinations using the Yama
5-cup and Yama 8-cup pots.
I can tell you from personal experience, though, that it doesn't matter how
short a time the water stays in the top... the vacuum starts forming as soon
as the first water flows upstairs, and there's a full vacuum formed by the
time all the water reaches the top. What you're describing is a stall from
lack of vacuum, which is different from a stall from fines clogging the rod.
I imploded a pot earlier this year with little or no linger time in the
funnel, proving that a powerful vacuum is already formed by the time all the
water is upstairs.
Doug
On Wed, May 13, 2009 at 2:52 PM, Jeff Kilpatrick
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16) From: Barry Luterman
Good advice
On Wed, May 13, 2009 at 11:52 AM, Jeff Kilpatrick 

17) From: Jeff Kilpatrick
Doug,
Over the years, I've done everything from C- to charcoal in my vacpots (what
can I say, I've been learning to roast like everybody else does, perhaps a
bit slower than normal).  Over the past two years or so, I've been using
mostly the 8- and 5-cup Yamas, both with cloth filters and the latter with a
Cory rod.  In that time, I've gone deep into 2C (even getting pits on
occasion).
I agree that vacuum does start forming as soon as the water starts going
north, but I would suggest there are two phases and getting through both is
important.  First, the water goes up and the vacuum should be proportional
to the loss of that volume.  Second, gas escapes the system through the
globe, creating a much stronger volume.  I don't even play a chemist or a
physicist on TV, but I do remember that PV=nRT --> P = nRT/V.  In our
system, R is Planck's constant (I think...), V is the (constant) volume of
the decanter, and T is temperature (and nearly constant).  In other words,
most of the change in pressure is due to change in the number of molecules
in the bottom.  In still other words: be sure to let that gas escape for a
nice, strong vacuum.
At any rate, I'm not claiming 9 minute drawdowns are impossible with
standard use, I've just never seen it.
On an unrelated note, I'm trying the wet-processed Bonko at City for the
first time this morning (ground at 19 on my fancy new Rocky and brewed in my
5-cup Yama with a Cory rod) and absolutely loving it.  It's got great
tanginess.
-jeff
On Wed, May 13, 2009 at 7:57 PM, Doug Hoople  wrote:
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18) From: Doug Hoople
Hi Jeff,
Interesting speculation on additional increases in vacuum strength. Maybe
you don't play a chemist on TV, but your recall of chemistry from your
school years beats mine. I was a liberal arts geek and didn't actually get
to chemistry, much to my chagrin now.
I'll have to scratch my head a little and see if I can't make sense of your
proposition.
In the meantime, a couple of comments, drawn from direct observation...
The Cory rod seems to be the most effective among the glass rods I've tried.
The 8-cup Yama poses more challenges than the 5-cup.
If you're clogged with fines, then a really strong vacuum won't overcome it.
It will break the pot instead if you don't stop it in time.
Consider yourself lucky that you've avoided this problem. There are several
people on this list who appear also never to have had it. Most of them have
a good reason, most often having to do with not brewing dark roasts.
When vacpots were common a century or so ago, the standard for roasting was
(I believe) a lot lighter than what we're seeing now, especially after 30
years of the bigs raising two generations of us to prefer roast artifacts to
origin flavors.
Doug
On Thu, May 14, 2009 at 9:18 AM, Jeff Kilpatrick
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19) From: raymanowen
There are grinders ["Good grinders"] for which everyone acknowledges the
advertising Palaver that says they are good grinders. Fits under cabinets on
countertop, has all kinds of shiny plastic parts, buttons and maybe two
dozen settings.
Advertising copy is tasteless, only the cup holds the proof.
If a grinder is truly good, it will produce nice-shaped coffee particles of
any size. That quality produces excellence in any cup.
If any particular machine will produce a good fine grind but not coarse-
*What* is the transition point where you have to start making excuses
instead of grounds? Suppose the Bean / Roast / Brew required to grind right
in the transition area? Can't be the beans/ roast/ barista- Excuse the poor
Grist Mill.
*
A- *When you turn the thing On, you have to start excusing the faults! The
microscope will tell the story before you even have to suffer the cup. The
cup is the final arbiter.
If the coffee grounds have a lot of fines in addition to the desired
particle sizes and shapes, you can take it to the bank that the grounds
themselves have fuzzy surfaces like the edges of torn paper. These fines,
whether or not they are still attached to the grounds, will rapidly infuse
and over- extract, giving their own flavor to the brew.
Grind adjustments will not overcome these fines. Since they're a much finer
constant than even your desired espresso grind, adjustments in the grind for
your shots will be pretty indistinct.The growers devote their families'
lives to the bean- Why Waste it?
Cheers, Mabuhay at magandnag Cafe sa Inyong Lahat -RayO, aka Opa!
Persist in old ways; expect new results - suborn Insanity...
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20) From: Michael Dhabolt
Sorry guys,  I just couldn't let this one slip by!  I've tried to pass
over it, but .....
A question: How could the rest of the water be forced into the upper
chamber if the lower chamber was at a pressure less than atmospheric
(let's call that a vacuum) at any time prior to all the water moving
north into the upper chamber?
Answer: It couldn't. It is the very slight steam pressure from the
water boiling in the lower chamber that exerts a pressure slightly
more than the atmospheric pressure at the upper chamber that forces
the water out of the lower chamber, up the tube and into the upper
chamber.
A question: When does the vacuum happen and why?
Answer: The pressure in the lower chamber changes when the water is no
longer boiling (producing steam), and the steam in the lower chamber
begins to condense back into water.  One drop of water takes up
considerably more volume when it is boiled into steam.  When the steam
condenses back to water it takes up less space, the lack of anything
in that left over space is what we know as vacuum.  Pressure tries to
equalize between the upper and lower chambers, the higher pressure at
the upper chamber (atmospheric) forces the liquid down through the
tube into the lower chamber (and usually a little extra air (the
gurgle) to fully equalize the pressure.
A little extra thinking:
A friend told me that he could usually get a good morning brew from
his Yama, but in the afternoon things just didn't seem to work as
well.  Come to find out, the local aeration pool for the city water
(shoots geysers of water into the air where the warm water absorbs a
lot of air) was only a block away from his house.  Yes, they only did
this in the afternoon.  When drawing a glass of water from the tap it
would immediately start de-aerating (real small bubbles would start
forming on the walls of the glass).
He changed his procedure.  He now lets the lower chamber finish the
nucleate boiling (small bubbles) and waits to see the beginning of big
bubble boiling (water boiling instead of the water de-aerating) before
putting the top chamber in place.  No more problems with in-adequate
vacuum
Mike (just plain)
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21) From: Jeff Kilpatrick
Mike-
First up, I don't mean to make any enemies here.  I just want to have a
productive fact based discussion.  My conjecture is based on science I
learned years ago, so I'm open to correction.  That said...
I don't think steam has much to do with it.  You can send water into the
globe at temperatures far lower than boiling (c.f. the thread on vacpot
preheating a couple months ago).  It's again a simple instance of PV = nRT
(the ideal gas law).  As T goes up in the bottom at the start of the brew, P
increases, which sends the water up (since there is increased pressure
exerted by the air in the bottom on the water).  Once the bottom of the
globe's tube is exposed to the air in the bottom, the decanter's air starts
to move north.  Since it gets to escape the system, P and T pretty much stay
constant at that point while n decreases.  When the heat is removed, T goes
down and since V can't change, P plunges and a vacuum is created.
-jeff
On Thu, May 14, 2009 at 3:20 PM, Michael Dhabolt
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22) From: Jeff Kilpatrick
Also, I don't think anybody is making this claim:
<Snip>
:-)
If my earlier comment was interpreted to mean that, I didn't communicate my
thoughts well.  Wouldn't be the first time!
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23) From: Ira
At 11:35 AM 5/14/2009, you wrote:
<Snip>
Here is I hope a clearer explanation of why you need to wait a bit 
after the water has gone up.
There are 3 things in the bottom bowl after the water has gone up, 
water, steam and air. Letting it bubble a bit after the water has 
gone up will likely replace some of the air with steam. Cooling the 
air in the bottom from 212 to 200 degrees causes it to want to reduce 
in volume a few percent, cooling the steam the same amount causes it 
want to reduce back to water taking up about 99% less space so the 
less air you have in the bottom the better the vacuum you have.
Ira
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24) From: Jeff Kilpatrick
Mike-
Okay, one last email on this subject and I'll be quiet.
I'll agree that oxygen leaving the water (nucleate boiling) probably does
occur.  Also, if the water does really boil in the bottom, the steam will
certainly behave as the rest of the gas in the system does, with the
exception that whatever is left in the bottom when the heat is removed will
condense.
At any rate, the thing is more complex than I acknowledged and I'll leave it
at that.  Makes tasty coffee though, which is probably the important part.
Sorry for the numerous emails!
-jeff
On Thu, May 14, 2009 at 4:27 PM, Jeff Kilpatrick
wrote:
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25) From: raymanowen
Wow!
"I agree that vacuum does start forming as soon as the water starts going
north..."
[That's a little tough to swallow]
The water goes North because the pressure in the South is higher than the
pressure in the North.
[image: \ pV = nRT] is the ideal gas equation, and could be transposed to
yield
*p = nR (T/ V)* Pressure is directly proportional to Temperature (abs K) and
inversely proportional to Volume.You are correct when you state:
"Drop out the constants and see that the gas flows away from the higher
temperature..."
The higher temperature of the heated water in the bottom raises its vapor
pressure. Since the top is open to the atmosphere, its pressure is constant.
The gas pushes the water ahead of it from the higher pressure in the bottom
up to the (constant) atmospheric pressure in the top.
"...but I would suggest there are two phases and getting through both is
important.
*First*, the water goes up and the vacuum [should?] be proportional to the
loss of that volume??
*Second*, gas escapes the system through the globe, creating a much stronger
volume...".[*??*]
[What the Sam Hell is a stronger volume and what are the units of measure?]
Pardon me- you meant vacuum, I apologize. You won't measure any appreciable
gas diffusion through the glass envelope. Why do that, when it can just flow
through open stem to the atmosphere?
Vacuum is always relative, and a perfect vacuum doesn't exist anywhere in
the universe, since it would mean the total absence of all matter. A vacuum
is a lower pressure with respect to any higher pressure.
*Don't* try to boil out all the puddle in the bottom. You can do it easily.
The glass bottom will get much hotter without the limiting water. The
descending coffee will be several hundred degrees cooler, and when it hits
the red hot bottom...
"OH! TOO MUCH VACUUM! Broke the pot!!"
Make another choice- that one was incorrect.
Cheers -RayO, aka Opa!
A sign on my darkroom door promised the kids that all of the dark would leak
out if they left the door open...
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26) From: Doug Hoople
"If a grinder is truly good, it will produce nice-shaped coffee particles of
any size. That quality produces excellence in any cup.
Not so fast, RayO.  Abstract maunderings like yours above are fine, but you
don't have data. I suppose you're going to tell us that the Mazzer Robur is
actually a crap grinder because it's not that consistent in the coarse
settings? There's a theory afloat that just about any decent flat-burr
grinder will produce more consistent coarse grounds than even the best
conical-burr grinder. So far, the data appears to back that up.
You can't just throw money at the problem (which is what you're suggesting).
You actually have to solve the problem with facts, not fantasies.
Doug
On Thu, May 14, 2009 at 12:43 PM,  wrote:
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27) From: Doug Hoople
Hi Mike,
You're absolutely right, and I apologize for overreaching in a category in
which I have little real expertise, namely, physics.
Doh! Of course there's no vacuum while the water's travelling north. Do I
feel stupid for having actually made that assertion? Yes!
Thanks for the correction.
As for your friend's experience, that's an interesting twist! I suppose it's
not really an issue at all if the "nucleate boiling" is complete in the hot
water kettle before being transferred to the vacpot, which makes this the
first non-arbitrary argument in favor of pre-heating the water instead of
running the whole cycle exclusively in the vacpot.
Thanks.
Doug
On Thu, May 14, 2009 at 1:20 PM, Michael Dhabolt
wrote:
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28) From: Doug Hoople
"Also, I don't think anybody is making this claim:"
Actually, Jeff, I was. Was suffering massive brain flatulence that was not
crippling enough to prevent me from typing. Mike was right to call me on the
carpet for it, and I've thanked him for that!
On Thu, May 14, 2009 at 2:27 PM, Jeff Kilpatrick
wrote:
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29) From: Doug Hoople
You're right, Ray, to find hokum in what I was writing here, but you should
find the right hokum.
I've already apologized for the stupidity of asserting that a vacuum forms
while water is travelling north.
But I won't apologize for the followoing:
""OH! TOO MUCH VACUUM! Broke the pot!!"
Make another choice- that one was incorrect.
*Don't* try to boil out all the puddle in the bottom. You can do it easily.
The glass bottom will get much hotter without the limiting water. The
descending coffee will be several hundred degrees cooler, and when it hits
the red hot bottom..."
Again, RayO, you haven't been paying attention to the facts.
The water travelled north, leaving a layer at the bottom, which acts as a
temperature buffer that prevents the glass bottom from overheating and keeps
the colder coffee above from direct splashdown onto hot glass . I let
everything bubble for 1 minute, and then took the pot off the burner and set
it down on a thermal surface for the drawdown. Standard operating procedure.
Noted a stall, left the pot to continue drawing down, and absent-mindedly
forgot about it. 12 minutes later, a sharp report issues from the kitchen,
which I knew to be the end of my 5-cup Yama.
You can't tell me, RayO, that the pot cracked from the sudden contact of
cold coffee on hot glass at that point. The temperature of both would have
been fully-evened out for at least 10 minutes prior to the big event.
Doug
On Thu, May 14, 2009 at 3:09 PM,  wrote:
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30) From: Barry Luterman
Perhaps a grinder which is geared down for lower RPM and greater torque will
result in a grind  of a dark roasted bean with less fracturing. Hence the
more expensive grinder will give a better grind.
On Thu, May 14, 2009 at 12:23 PM, Doug Hoople  wrote:
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31) From: Barry Luterman
I might be able to settle this. I have a Bodum Vac pot with a cory rod which
hasn't stalled in 5 years. I also have a Mazzer Mini, Flat burr grinder and
a Cimballi max Hybrid conical grinder. Next time I roast I will waste a half
pound of beans by taking it to Vienna (it will kill me to do it). I will
then try and pull vac pots using both grinders. However, I will not drink
the swill. I will report back next week.The things I do for this list.
On Thu, May 14, 2009 at 12:53 PM, Barry Luterman wrote:
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32) From: Michael Dhabolt
Jeff,
Jeff Kilpatrick wrote:
<Snip>
We are in absolute agreement.
Mike (just plain)
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33) From: Rich Adams
The instructions included with the Yama's say to start with pre-heated 
water.  No argument needed. :-)
Rich Adams

34) From: Doug Hoople
Hi All,
My apologies for making this thread grumpy and contentious. That certainly
wasn't my intent. It seems we've avoided an all-out flame war, in spite of
the gas I've thrown on, and in spite of making a boneheaded layman's
assertion about the physics of vacpots that even the simplest of common
sense should have prevented me from making.
I'm not a physicist, and I don't know gases. I have to say that the
discussion of them on this thread has stirred my interest, and that there's
more going on than I've paid attention to until now.
None of my claims about vacpot stalling have been based on the nature of the
vacuum, except to say that I've assumed that the vacuum was present and
sufficient. I don't believe that any of the stalling I've experienced has
been from the absence of the vacuum.
All of what I know about vacpot stalling comes from direct observation. I've
stumbled into a combination that appears to create a perfect storm, namely
dark roast coffee brewed in a vacpot with a glass rod drainer.  I can
work extensive gradations of drawdowns from 30 seconds to 4 minutes to 10
minutes to hard stall with the tools I have. While I don't have powers of
perfect prediction, I've gotten to the point where I can say in advance
that, for example, one pot will draw down normally, another will run a
little slow, the next will run very slow. With the grinder I have, I can get
French roast to draw down in the 8-cup Yama in as little as 30 seconds or I
can get it to stall hard. Oddly enough, the hard stall comes at the coarsest
setting, and the 30 second drawdown comes at the finest.
So, while I haven't got the science, I do have the direct experience. Let's
not forget the story of John Harrison as we invoke all the science. Nobody
wanted to believe that the Longitude Prize should be awarded to a "simple
uneducated tradesman," but Harrison was on the pulse. While they
spent decades denying him the prize on technicality after technicality,
Captain Cook was safely navigating the globe using one of Harrison's
timepieces.
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35) From: Doug Hoople
"Perhaps a grinder which is geared down for lower RPM and greater torque
will
result in a grind  of a dark roasted bean with less fracturing. Hence the
more expensive grinder will give a better grind."
The Mazzer Mini runs at 1600rpm.
The Cimbali Max Hybrid runs at 800rpm.
 The Baratza Virtuoso runs at 450-500rpm.
If your Max Hybrid can deliver really consistent very coarse grounds, Barry,
it won't be because of the RPM. All conical-burr mills run at lower RPM than
flat-burr mills. If flat-burr mills are the solution (yet to be proven), RPM
is not the deciding factor.
Doug
On Thu, May 14, 2009 at 3:53 PM, Barry Luterman  wrote:
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36) From: Doug Hoople
Since this is about drawdown mechanics and not about taste, the results
don't have to be drunk. If Vienna's that offensive, and you're really
wasting your half-pound, Barry, then you should take it all the way. Go
French! It's the French roast that amplifies the grinding distinctions in
this case, and you'll get much bigger swings in the drawdown from it. If
they show up at all, they'll show up big with French.
Doug
On Thu, May 14, 2009 at 4:16 PM, Barry Luterman  wrote:
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37) From: james McDougal
Thanks everybody - interesting discussion. Since I just got a 5 cup Yama,
I'd like to know what coffee ratio you all use. In the tip sheet, Tom
suggests 7.5 g per 150 ml - That would be 30 g for my 5 cup Yama. I like
strong coffee so I made my first pot with 40 g and it was pretty good, but
I'd like to know what coffee/water ratios others use.
Thanks, Mac
On Fri, May 15, 2009 at 11:10 AM, Doug Hoople  wrote:
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38) From: Doug Hoople
If you like your coffee strong, 40g is a pretty good number. 30g makes a
nice pot of coffee, but it is a little on the weak side.
Generally, I've been using 40g for my lighter roasts, less for darker. Seems
about right.
Doug
On Fri, May 15, 2009 at 9:23 AM, james McDougal wrote:
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39) From: Doug Hoople
"The instructions included with the Yama's say to start with pre-heated
water.  No argument needed. :-)"
Oh man, Rich, get a thread! We're all booked up on this one!
Doug
On Fri, May 15, 2009 at 6:32 AM, Rich Adams  wrote:
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