Thursday, August 2, 2012

Coffee Talk - Cory Vacuum Pot (The Vac-u-lator)

I was riffling through the "Coffee Talk" posts of the past the other day and I realized, with some distress I might add, that I have never ever divulged my absolute most favorite way to make coffee.

The "Vaculator", or what is more commonly referred to as Vacuum pot or Siphon pot.

To me, this is the epitome of home coffee brewing.  Sure, the Moka pot makes a nice cup of near espresso, and the French Press makes a deliciously rich cup of "joe" to accompany your dessert.  I can even say, with no small amount of conviction, that "pour over drip" (though Chemex brewing takes some degree of finesse to perfect) is quite delicious.  In fact, there are several brewing methods that produce delicious coffee, but I think vacuum brewing beats them all.

I think the reason I have never mentioned it before, is that I have taken it for granted over the years.  You see, I have a Bodum Electric Santos (Sold under the Starbucks Utopia label back in 1999) that was gifted to me by a friend when I helped him move.  I had never seen a vacuum pot before, but once I brewed coffee in it, the auto drip I had been using quickly went bye-bye, for it brewed a vastly superior cup of coffee.  One that truly lived up to the label on the pot.  For that first cup was "Utopia".

It's 13 years later and I still use this pot every single day.  I absolutely LOVE it.  Though that love has been strained twice in the last decade... The nylon filter eventually "wears out" or tears and needs to be replaced.  They only cost $4.50, so it's not a monetary issue so much as it is the fact that the Bodum site always lists them as being "on back order".  I have had to wait up to 3 months to get a replacement filter...  Luckily I have a French Press and a Corningware Drip-O-Lator waiting in the wings to pick up the slack.  Lesson learned. NOW I am prepared for any unforeseen tearing or clip breakage by having 2 extra filters hiding in my pantry.

There is only 1 coffee pot that I can think of that brews a better cup of coffee....  and that would be this art deco era beauty right here.

A vintage 1930's Cory Glass Vacuum Pot with a glass filter rod.   So classic in style, and so inspired in functionality.  No plastic, no cloth, no paper, no metal.... Absolutely nothing to interfere with the volatile oils of the extracted coffee.  Just water, coffee grounds and inert glass.   It is truly a beautiful thing.

Sadly, the Cory company went defunct decades ago. (though Silex made these as well) The reason was two fold...  First there was the rise of the Auto Drip coffee maker.  Let's face it, automatic brewing machines are a lot easier to use than a manual stove top coffee maker.  I don't know about you, but personally; there is NO WAY that I am capable of manually making coffee in the morning...  It's like Dawn of the Dead around here until the first cup of coffee has been consumed.

While I have no doubt that auto-brewing was at least partially responsible, I believe the main reason for the demise of the vacuum brewer was that it's greatest attribute was also it's greatest weakness.....It's made of glass;  completely from glass.  Even though it's made of Pyrex's borosilicate heat resistant glass which is virtually impervious to thermal shock, it's not resistant to shocks in the kitchen.  One false move with the siphon tube while cleaning the upper bowl and you have a lovely pile of coffee ground covered shards in your sink.  But for me, the superior quality of the finished brew far outweighs the extra care that is needed during clean up.

My vacuum pot is significantly older than I am....  Actually, it's significantly older than my parents too.  As a result of it's advanced age the rubber seal on the upper bowl has become hard as a rock.  It softens to a more pliable state once it has been warmed, but it still doesn't form a good seal anymore...It IS 75-80 years old after all.  There is an online source (DaySeal) where you can order new gaskets for $25, but I figured out a temporary fix.  So, if you happen to have one of these pots and the gasket is hard (not cracked) then I am going to show you a little trick to make your pot work almost like new.  After all, it is a sad thing to leave one of these beauties boxed away and unable to fulfill it's coffee brewing destiny.

All you need are 3 Rubber bands from Asparagus you bought this last spring.  (you save your produce rubber bands, right?)

Oh, you don't like asparagus?  What a shame that is.  Oh well, I guess that means there is more for me.  ;) OK, grab 3 thick produce type rubber bands (I know they use them on leek bundles too)

Slide one of them over the gasket and move it up towards the point where the upper part of the gasket touches the bottom of the bowl.  (It is important not to twist the rubber band in any way)

Gently guide it over the edge of the gasket and down in between the bowl and the top of the gasket.... This will form your upper seal.... (this is also why it is important not to let the rubber band get twisted... It needs to be nice and flat to form a seal)

Now take the other two rubber bands and place them around the ridges on the lower part of the gasket. (Again, do not twist the rubber bands)

There!  You have just reconditioned your gasket for use.  I guarantee you can now use that old vacuum pot (at least for a little while) without shelling our $25 for a new gasket. Just watch....

Fill the bottom pot with water, no higher than the DRL printed on the bottom pot... In my case, this is the 8 cup mark.

Place this over medium flame (no higher) and allow to come to a simmer.  (If you have an electric coil stove you should have a wire star to prevent actual contact with the coil, though I have seen people use these directly on the coil before)

Once the water in the lower pot comes to a simmer, run the filter rod under cold water and place it in the upper bowl.  (the pebbly texture prevents the grounds from entering the lower bowl during the final siphoning)

Place the ground coffee in the upper bowl.  1 TB per cup and an extra one for the pot for a total of 9 TB. (Your grind should be coarser than Auto-Drip grind, but not as coarse as French Press grind)

Place the upper bowl on top of the lower bowl, then press gently and twist to the right to form a seal.

Now it's a waiting game... as the water below begins to turn to vapor, the pressure will begin forcing the hot water up the tube and into the upper bowl.  (it's all based on atmospheric pressure and water displacement, but am going to refrain from completely "geeking out")

Eventually, the water in the lower pot will drop lower than the end of the siphon tube... THIS is what you have been waiting for...  The steam in the lower pot now has the ability to escape up the tube. As this steam bubbles up through the water and grounds in the upper bowl, it churns everything around, creating greater contact between the coffee and the water and as an added bonus, it keeps the water in the upper bowl at the correct brewing temperature of 195-200 degrees. How brilliant is that?

Let it churn for 60 to 90 seconds.

Then simply remove the pot from the flame and allow it to cool... This is where the magic begins.

As the lower pot cools, the steam that is left will begin to cool and condense, thus there is now less pressure in the lower bowl.  The lower pressure below begins pulling the coffee infused liquid, in the upper pot, down into the lower pot in an effort to equalize.

Now, since some steam escaped during the "churning", the pressure in the lower pot is actually "less" than what it displaced before. (I hope that made sense) As a result, there is more "suction" than there is water in the upper bowl, this leads to the gasping sound at the end as the lower pot sucks air in through the grounds as well.  This little burst of drawn air at the end is powerful enough to "suck" the coffee grounds almost completely dry.

Remove the upper bowl and lay it CAREFULLY in the sink...

And there you have it..... Delicious coffee just like they made it back in the 30's... or as I like to call it "Coffee AND a show"

Now, pour your self a nice cup of super rich and super smooth vacuum brew!

Cin Cin!!


Patti T. said...

Pass that beautiful vacuum pot over here so I can pour myself a cup. I can't even imagine how good it must taste.

Bernice Peterson said...

I just found a New Cory Rod with 3 U.S. patents on it in the bottom of a box in the pole barn and googled those 3 words that are on it to find out what it's for. I had a hunch that Cory was something to do with coffee. BUT this rod cannot filter coffee because it is solid glass! I know that for sure because the rod part below the bottom square is broken. So I'll mend it and it would work in a wine or fancy perfume bottle, the rod part being only 2 1/2" long. Do you know why it is a solid glass rod?
Thanks for help. Bernice in OR

The Vinyl Frontier said...

Ah, but it DOES "filter" the coffee - it holds the grounds while letting the water pass.

Fortunately, my Cory is a slightly later model which has no rubber seal - sealed only with vacuum pressure. I love mine, too; but I only use it when entertaining - I never make coffee in the evening any other time. However, it's quite the conversation piece!

Unknown said...

Is there a market for the rod today?

Shane T. Wingerd said...

Sure... I see the rods listed on eBay all the time. :)

Unknown said...

Where can I fill out $25 for a gasket instead of using rubber bands

Shane T. Wingerd said...

You can still find replacement gaskets at Dayseal - here:

notagain said...

I'm happy to have found this post. I just recevied mine from shopgoodwill and it worked quite well. Wonderful info, thanks for putting it together!

Beanie and Cecil said...

Yes, the Dayseal gasket works beautifully. Made of food grade silicon. Soft and very flexible.

Gail said...

I found one of these in a thrift store many years ago, and bought it to add to my collection of Cory coffee pots. I am distantly related to the Cory family that started this company. I had no idea how to use it until I met an older gentleman whose father worked for at the Cory factory. He explained how to make it work, and it still makes the best coffee I've ever tasted!

Unknown said...

Hi, I have a small collection of vacuum pots, 67 I think. I love my Cory DCU/DCL rubberless pots, I have 7 of that model. Steve

Unknown said...

I have one but it doesn't have all the pieces. Can you tell me what to sell it for

Unknown said...

I have both the Cory DCL and a Silex. The Silex has an extra glass filter and original cloth strainers. I am looking to sell both as I am remodeling and will never use them. 336-407-5859.

connie said...

I just took out my very old Bodum Santos Electric Vacuum Coffee Maker and decided to check online who is still using it. LOL.... I just brew water in it. It is still working.....Praise the Lord :D :D :D

Jeff Kindgren said...

Does anyone know if dayseal is still in business?

Unknown said...

A few Vac Pot comments.

I am a Vac Pot collector and have about 60-70 different makes and models in my collection. A really good on-line source for info about Vac Pots is a web page by another collector, Bryan Harris -

Vaculator is actually a trade name of the Hill-Shaw Company of Chicago, which also made the JAVAC brand in addition to the Hill-Shaw brand.

Over the heyday of the Vac Pot - 1930-1955 - there were probably 20-30 companies in the US making Vac Pots, though the vast majority of the glass was manufactured by the Pyrex division of Corning Glass on contract. They invented the boro-silicate heat resistant glass that made the Vac Pot practical.

The grind recommended by Cory is usually described as medium fine. My Cory DEG coffee grinder has a setting called "Cory" that is finer than drip but not as fine as espresso. And if you look at those lovely Hobart behemoths that used to grace grocery stores, the "Vac Pot" setting is between "Fine" and "Drip".

If you get the grind too fine, the filter will plug and the brewed coffee will not fully return to the lower pot. I've found that the inexpensive chopper/spice grinder coffee grinders produce to wide a range of coffee ground sizes - too many fines and big chunks, too, so I use a burr grinder. The Cory DEG is actually made by Hobart.

GE (and others) made automatic Vac Pots. My daily brewer is a GE automatic. You plug in the special hot plate, put on the filled pot and press a button that switches the hot plate to high mode. When the water rushes up to the upper chamber, a piston in the bottom of the dip tube lifts and turns off the hot plate allowing the coffee to "come on down". When the hot plate cools to the keep warm temp it switches to low mode and thermostatically keeps the coffee at a nice drinking temp. It is quite an elegant design, both technically and aesthetically.

Cory, Sunbeam, Westinghouse and Knapp-Monoarch all made automatic chrome plated copper Vac Pots. Cory, Silex, Nicro, Bloomfield and others made stainless manual vac pots. I have three different size Cory's that are my go to camping and motel room pots. Duralux, ABCO, Mirro and others made manual aluminum pots and Cory made an aluminum automatic pot.

I have taught myself and purchased the equipment necessary to cast replacement silicone gaskets for my collection.

I remember when I was a very young lad in the early 50's there were diners that had batteries of Vac Pot brewers. In larger joints, there was a "girl" during the breakfast and linch rushes whose job it was to keep the all the Vac Pots going.

-Gray Haertig
Downriver in Portland