Photos

Settling out . . .
A couple moments after ending the extraction.




Ready
About half a minute later.

Intentions-

I want to include all the information necessary to make good espresso on the Presso

That is, all the information that is specific to the Presso- grind and tamping are the same for the Presso as other machines.

If you see anything missing or disagree please contact me, I will be happy to make changes and give credit for any additions. (lever dot related at gmail dot com)

Please read the entries in order as they (in a small way) build on each other. Note especially the last entry: Broken! (fixed)

I want to thank Jim Schulman for his page about the Presso, as well as the following posters on alt.coffee and home-barista.com - hazzmat, Paul Sack, Luthier, and those people who posted about the $5.99 Pressos!

-> This is not a real Blog, the dates have been altered to control the order in which the articles appear.

Tribute to Presso's designers . . .

The Presso is simple. It can be taken apart completely.

It is attractive.

It can make quite good espresso.

I think it's great.

I don't know who designed it. <-- scratch that-

It seems the Presso was designed by Patrick Hunt and Martin Riddiford of Therefore Design, a British design company. It won many design awards in 2004.

Riddiford and Therefore Design are best known for their work on the Psion PDA.

Warming (general)

Most Espresso machines brew at 92-96C. If you simply pour boiling water into a cold Presso the water will be far below this temperature by the time it meets the coffee. It will be further cooled while pouring from the portafilter basket through the portafilter and is unlikely to taste good.

How much you need to warm it depends on the ambient temperature and the temp of the water you are pouring into it. If you are making espresso in your unheated basement in the dead of winter you will need to do a fair bit of warming up. If your Presso has been sunning itself at the beach you could probably get away with no warm-up at all.

In any case the water you use for brewing should be as hot as possible, so work out a way to pour just-off-boiling water directly into the Presso's pressure chamber.

I've prepared two methods, for "The Dead of Winter" and for a comfortable room temperature environment.

Warming "The Dead of Winter"

There are many ways to go about warming it up, the important thing is consistency. The following is the procedure I use-

Note- it is necessary to use water that is fresh off the boil, and to bring water to a boil repeatedly, so work out a way to do this.

Note- Holding water in the Presso will warm more effectively then just pouring water through. To this end you will need a way to plug up the spouts of the portafilter (I use the ends of two bamboo chopsticks).

1. Begin with the piston removed (see the 'Cleaning and Drying' entry).

2. Bring about a Litre or 4 Cups of water to a boil. With the Portafilter (sans basket) in place, pour about two chamber's worth of water through the brewing system into a bowl.

3. When done pouring, replace the piston and re-connect the arms.

4. Push the arms down and insert plugs into the Portafilter's spouts.

5. With the arms in their lowest position, begin pouring boiling water into the chamber while raising the arms. Stop when the arms are at the highest position.

6. At this point the chamber is nearly full, but there is still a lot of air trapped in the portafilter. You need to 'pump' the arms to force the water through the dispersion screen and release the water.

7. Slightly lift one of the arms (to open up the holes in the piston head) and pour water through the piston head to fill it completely.

At this point you can begin boiling water for brewing and fill the basket with coffee.

This procedure can be repeated if necessary.

Warming from Room Temperature

With the piston removed or in place, simply pour a quantity of boiling water through the Presso into a fair-sized receptacle below the spouts.

This can be repeated by pouring the 'used' water back into your water-boiling device.

Yer all set to go!

Dosing into the basket

With most espresso machines it is common to grind, dose, and tamp with the basket in the portafilter.

However, if you are having trouble getting the temperature high enough then removing the portafilter for a long time should be avoided. The simplest way to avoid the pf cooling is to dose and tamp directly into the basket. This way the portafilter is only removed from the machine for the time it takes to drop in the basket and little heat is lost.

With this method it is important to remove the 'clip' that holds the basket tightly in the portafilter. If it is left in you are forced to 'snap' in the basket which can disrupt the tamped grounds and result in poor (uneven) extraction.

Portafilter cooling-
5 seconds - <5F
30 seconds - 5-10F
60 seconds - 10-20F
Home-barista.com thread and alt.coffee topic

note- unless the ambient temperature is very low or you are obsessed with temp stability (!) this technique is not necessary.

Dosing- Overdosing!

I've been packing 23 grams into the standard double basket.

This is far more then the usual 15-19 grams for a double basket.

I put in this amount so the tamped grounds reach the dispersion screen, which I believe is much higher than on other espresso machines.

If I pack 15g at 30lbs (approx) the grounds will not swell to meet the screen, and they will be pockmarked by the force of the water coming through the screen.

UPDATE

I've found that good results can be obtained with much less coffee . . . the jury is out for deliberation.

Why is this not a problem with the Presso?

Perhaps because of the gradual pre-infusion? (more soon)

Pouring

It is important to disregard the instructions included with a Presso. Following the standard instructions for filling the Presso's chamber will trap air in the chamber. It is not necessary to create a plug to fill this gap, simply following these alternative pouring instructions will completely fill the chamber with water and force out all the air.

It might be easier to practice with room-temp. water till familiar with the sequence.

EASY

1. Raise the arms to their highest position and hold up.*
2. Begin pouring water on top of the piston. If water begins to build up on top of the piston jiggle the arms slightly, pour more slowly, or 'pulse' the water flow.
3. Continue pouring till there is no air visible under the piston and the chamber is completely filled.

There is still a bit of air trapped at the top of the piston which is impossible to eliminate due to the position of the holes and the concave shape of the piston head.

*it is important to hold at least one arm up to open the holes in the piston head.

EASY + FAST

1. Start with the arms in the lowest position.
2. Begin to pour the water while slowly raising the arms. Try to keep a small reservoir of water on top of the piston
3. Stop when the arms are raised to the highest position. Check that there is no air trapped under the piston head, 'top off' if necessary.

BETTER*

Assuming you are making a standard 2oz espresso it is not necessary to raise the arms/ piston to their highest positions.

Start with arms (and piston) all the way down.

Pour in boiling water while slowly raising one lever/arm.
(you can raise the lever with one hand as there is little resistance)

Continue raising the arm till the bottom of the piston has cleared the metal body.

At this point stop lifting up, but continue slowly pouring in water while 'jiggling' the arm.
(This will allow water to replace all the air trapped under the piston. You will be able to see how much air is left, continue till there are just 6 small bubbles trapped inside the piston.)

Now press down!

*Better because you won't have so much water left over at the end of the shot.

Multiple shots

Taking out the portafilter right after a shot can be a messy business. A Presso's chamber, unlike most lever machines, can hold much more then a double's worth of water, and any left over after extracting will simply simply sit in the basket.

Fortunately getting this extra water out is quite easy and straightforward. Without removing the portafilter, place a container under the spouts, raise the levers, and press down. When fizz starts coming out you can stop pressing and remove the portafilter. At this point the puck will be perfectly dry and can be knocked out with no mess.

As this can take some time, be careful not to overfill the chamber in the first place. If the lower edge of the piston is level with the top of the metal frame there is more then enough for a generous double shot.

The Presso will still be quite hot at this point so there is no need to flush it with boiling water, you can go ahead and pull another shot.

Cleaning and drying

With the removal of a single screw-pin all parts can be taken out and cleaned.

The two arms are connected to the piston at the top by a single screw-pin*. Taking this out will allow the piston(1), cylinder(2), and dispersion screen to be taken out and cleaned.

This will also allow all parts to dry completely, which would not happen otherwise.

* Keep this loose. It is not necessary to tighten it completely.

(1) Take care to position the piston correctly (aligned with arms) when replacing it.

(2) The cylinder can be removed by twisting it counter-clockwise and lifting. Reverse to replace.

NOTE: the cylinder can be difficult to remove until everything cools down.

Broken! (fixed)

My Presso broke. I was very upset. It is fixed now but our relationship has changed . . .

I would suggest that anyone who uses the Presso for espresso to prepare for this eventuality. Find someone who can weld aluminum and add more material at the weak spot, get a set of back-up arms, buy another Presso . . .

I learned the hard way (when welding the arms for the second time) that it is VERY important to align correctly the parts to be welded together. I had to trim both the plastic chamber and the piston 'rod' to get the two arms to attach correctly. In spite of being very unattractive it works well.

Pictures at modifiedpresso.blogspot.com


UPDATE: (apr03/06) Another part broke, this time the head of the piston where it meets the vertical plate connecting to the arms. I couldn't get a good picture unfortunately. I knew it was coming, as I could see little cracks developing over the weeks. Well, time for a real modification, replace the whole piston! (hmph...or buy a different machine! no, no, I didn't say that . . .)