Olympia Cremina Missing Crema - Do I Need Better Technique?

[hperry]

I recently purchased an Olympia Cremina on an ebay auction. I was very pleased to find that, although made in 91, it was in pristine condition. Seals perfect, no leakage, cosmetically like new. Checked it out at Home Espresso repair in Seattle who do a significant number of Cremina repairs and got a positive report.

I am curious: following the techniques here I quickly discovered and learned how to avoid fractured pucks. I'm actually getting quite good tasting shots. But they are producing almost no crema. The particular coffee I use doesn't produce a lot - but with the Bezerra I get a nice sheen of crema on top. So far, only a crema "accent" with the Olympia. Looking at the shot pictures on this thread I know whatever's happening must be me. I have tried to reproduce the approach listed here. If anyone has any ideas I'd appreciate feedback.

[hperry]

I guess I have my own answer. Must have been the coffee primarily. Bought a bag of Vivace Vita - nice crema. Had them pull a shot there, then, pulled a shot at home. Theirs was a tiny bit better, but not much.

I recently purchased an Olympia Cremina on an ebay auction. I was very pleased to find that, although made in 91, it was in pristine condition. Seals perfect, no leakage, cosmetically like new. Checked it out at Home Espresso repair in Seattle who do a significant number of Cremina repairs and got a positive report.

I am curious: following the techniques here I quickly discovered and learned how to avoid fractured pucks. I'm actually getting quite good tasting shots. But they are producing almost no crema. The particular coffee I use doesn't produce a lot - but with the Bezerra I get a nice sheen of crema on top. So far, only a crema "accent" with the Olympia. Looking at the shot pictures on this thread I know whatever's happening must be me. I have tried to reproduce the approach listed here. If anyone has any ideas I'd appreciate feedback.

[srobinson]

Well, I am bad at pulling shots and taking pictures, but this is what I am getting on the Olympia that I just rebuilt. This pic is actually the first pull on a double basket. They don't call them Creminas for nothing.



Now if you are not getting close to this, then walk us through your process....coffee, grinder, distribution, tamp, process etc. We'll get you tuned up.

[hperry]

That's a great looking shot! Your "restoration" thread was what piqued my initial interest in these machines. Appreciate help in tuning things up - I feel pretty competent with the Bezerra, not so with the Olympia.

So, in order:

Coffee - have tried 3 different beans. An Arabica roasted quite dark, with a light oil sheen. This is the bean I usually use with the Bezerra for morning lattes. I have this one down with the Bezerra - lighter crema than others but really enjoy it. It's smooth with the Olympia, but almost no crema. The other two coffees are Dolce and Vita from Vivace. With the Dolce, pulled as a 3/4 oz ristretto consumed straight, I can come close to matching what I have at Vivace. The Vita, which I use for milk drinks is smooth, but loses some richness and depth. Both have nice crema.

Grinder - is a Versalab M3. Has combination of conical and flat burrs. Distributes the coffee very evenly directly into the portafilter - although it is slightly more suited to a 58mm portafilter. On the Bezerra this grinder has been the single biggest improvement I've had in coffee - although it produces a "fluffier" grind which I had to learn to work with.

Distribution - use my best imitation of the Schomer North/South/East/West distribution. Overfill the portafilter, then level to the top.

Tamp - using Reg Barber convex tamper. Have tried both a light tamp and around 30 to 40 pounds. Doesn't seem to make a whole lot of difference. Tamp brings the coffee approximately to the level of the top of the tamper head.

A couple of process "things:"

Following the guidance here I keep the portafilter pretty loose until shortly before the water flow. This does help not fracturing pucks although I'd like to have one more hand for the process. Still, better than half the pucks are pretty shattered.

I know that the lever should be lifted to the top and allowed to stay there until the coffee starts to drip. Usually, it does not do so, although a steady "down" pressure readily creates a rich coffee if not continued beyond about 60% of the downward arc. After that it seems to blonde really rapidly. I don't like the taste of the second pull when I have tried it. The Vita ristrettos, stopping at about 60% of the way down are really good - could probably wean me away from milk drinks.

[srobinson]

OK, well let's start working on this problem and knocking out the variables. First you don't have a grinder problem. I would like to see how you get the Versalab to work with 49MM filters without leaving a mess all over the place, but we will leave that discussion until after we have you pulling gosh shots.

I am also going to assume that your coffee is OK. Based on your other equipment and being in Seattle, I assume you are able to get good beans within a week of the roast. If you have any doubt, then go to Hines or do a mail order from one of our sponsors and we can knock that variable out.

So, little to no crema means that you are not getting enough water at the right pressure through the puck. Water is either going around, you are not pulling hard enough or your gaskets are a bit old and you are not getting full pulls.

So what I would do:

1) Let's get the grind right and at the same time the strength of the pull. I always like to start by setting the grinder to the point where I can choke the machine with 40lbs of pressure on the handle. Now this is alot, but that is what it takes to get a shot like the one above. Once you get to that choke point, you want to back off your grind until you can maintain a thin stream of coffee with the same 40lb pull. Now don't bend the handle, but you want to get to the point where you are applying steady pressure and letting the machine do the work. Now if you do not have solid pressure throughout the pull, or you feel it slip or go soft during the pull then we have old gaskets.

2) I don't like your comment about the puck breaking. On a Pavoni, I would be nodding my head in agreement, but this is an Olympia. The action on your lever should be extremely smooth. If properly working the piston gaskets will contract on the upstroke and then expand on the downstroke...this is a major design advantage of these machines and the purpose of those silly holes that I mentioned in my posts. Assuming that you did not have them replaced when you had you machine checked out, I would bet that you are due for some new ones. This will also give you an opportunity to lube the shaft and knock out the variable that would mess up your lovely puck. The quick test on the gaskets is whether the handle mysteriously raises as the machine cools down. If it stays put in the down position, then order a new set of gaskets.

3) Finally if your grind is right, you can pull with the right amount of pressure and the lever is working properly, then you are down to your tamp. Sounds like you know what you are doing and I assume your tamper properly fits the basket. Just make sure you finish the edge out and are not polishing with force. I doubt this is your issue.....I will put my money on gaskets and then on force of pull as where you will get the biggest improvement.

I assume that you are seeing this on all shots. On the first pull, make sure and open the steam wand up the first time the light goes out. You want to release that false pressure. I also assume that the guys checked your pressure stat to make sure you are getting good pressure. I worry about the pull pressure more than the boiler pressure...so let's start there.

Give this a look and let me know if any lightbulbs come on.

[hperry]

Steve,

Thanks very much for your thoughtful and comprehensive reply. Here's what I have found as I have tested following your suggestions.

The lever does not rise as the machine cools. The shop that checked the machine, which is well regarded and has done a number of Olympia repairs, thought the gaskets were good - indeed I doubt if the machine has been used once or twice, if ever. We did make a couple of cups of coffee at the shop where things seemed to work OK. But I imagine that the gaskets could harden over time even if (or because) they were unused. The shop that repairs them manufactures their own gaskets for the machine so I could easily have them replaced. I also could order original equipment ones if available. One thing that doesn't happen is that when the lever is drawn to the top, there is no initial dripping coffee before depressing the lever. I thought at first that maybe I was grinding the coffee too fine, but perhaps that is also a gasket symptom? I don't seem to get the dripping even when the grind is coarser.

On the Bezerra my preferred shot is a ristretto. On the Cremina if I do a full lever pull I get about two ounces of coffee - nearly one ounce more than would be ideal. I get a nice dark mouse tail at first. About half way down the pull either the shot "blondes" or maybe that is the crema. In any case if I pull to the bottom I get an inoffensive shot but thin tasting, without deep coffee flavors and nowhere near the crema your pictures show. If I stop about half way I get some of the depth that I get on the Bezerra ristrettos, but little crema. I have had a couple of shots of Vivace Dolce that I liked as well as those that Vivace made on the Synesso at their shop - and there was some, although not a lot, of crema. My command of the descriptive terms is unfortunately pretty poor at this point.

The coffee at the time of testing with 3-4 day old (dated) coffee from Vivace. Should have been at its prime.

I think that I am applying about a 40 pound pressure on the lever. Resistance is steady after initial low resistance travel of perhaps 1/16 or so of the total distance. I haven't yet tried grinding tight enough to actually stall the system, so maybe I don't have the grind tight enough yet. However, the fact that I get no dripping when the lever is pulled up makes me a little reluctant to go any finer.

The more I write, the more it sounds like the gaskets - I'm puzzled why the shop that looked at them thought they were good. If you agree will I be OK using the ones they manufacture - or is there a source for manufacturers gaskets that I should be looking for?

The tamper is a Reg Barber convex, designed for the Olympia. It seems to fit like a glove.

Thanks again for your input.

OK, well let's start working on this problem and knocking out the variables. First you don't have a grinder problem. I would like to see how you get the Versalab to work with 49MM filters without leaving a mess all over the place, but we will leave that discussion until after we have you pulling gosh shots.

I am also going to assume that your coffee is OK. Based on your other equipment and being in Seattle, I assume you are able to get good beans within a week of the roast. If you have any doubt, then go to Hines or do a mail order from one of our sponsors and we can knock that variable out.

So, little to no crema means that you are not getting enough water at the right pressure through the puck. Water is either going around, you are not pulling hard enough or your gaskets are a bit old and you are not getting full pulls.

So what I would do:

1) Let's get the grind right and at the same time the strength of the pull. I always like to start by setting the grinder to the point where I can choke the machine with 40lbs of pressure on the handle. Now this is alot, but that is what it takes to get a shot like the one above. Once you get to that choke point, you want to back off your grind until you can maintain a thin stream of coffee with the same 40lb pull. Now don't bend the handle, but you want to get to the point where you are applying steady pressure and letting the machine do the work. Now if you do not have solid pressure throughout the pull, or you feel it slip or go soft during the pull then we have old gaskets.

2) I don't like your comment about the puck breaking. On a Pavoni, I would be nodding my head in agreement, but this is an Olympia. The action on your lever should be extremely smooth. If properly working the piston gaskets will contract on the upstroke and then expand on the downstroke...this is a major design advantage of these machines and the purpose of those silly holes that I mentioned in my posts. Assuming that you did not have them replaced when you had you machine checked out, I would bet that you are due for some new ones. This will also give you an opportunity to lube the shaft and knock out the variable that would mess up your lovely puck. The quick test on the gaskets is whether the handle mysteriously raises as the machine cools down. If it stays put in the down position, then order a new set of gaskets.

3) Finally if your grind is right, you can pull with the right amount of pressure and the lever is working properly, then you are down to your tamp. Sounds like you know what you are doing and I assume your tamper properly fits the basket. Just make sure you finish the edge out and are not polishing with force. I doubt this is your issue.....I will put my money on gaskets and then on force of pull as where you will get the biggest improvement.

I assume that you are seeing this on all shots. On the first pull, make sure and open the steam wand up the first time the light goes out. You want to release that false pressure. I also assume that the guys checked your pressure stat to make sure you are getting good pressure. I worry about the pull pressure more than the boiler pressure...so let's start there.

Give this a look and let me know if any lightbulbs come on.

[espressoperson]

The lever does not rise as the machine cools. The shop that checked the machine, which is well regarded and has done a number of Olympia repairs, thought the gaskets were good - indeed I doubt if the machine has been used once or twice, if ever. We did make a couple of cups of coffee at the shop where things seemed to work OK. But I imagine that the gaskets could harden over time even if (or because) they were unused. The shop that repairs them manufactures their own gaskets for the machine so I could easily have them replaced. I also could order original equipment ones if available. One thing that doesn't happen is that when the lever is drawn to the top, there is no initial dripping coffee before depressing the lever. I thought at first that maybe I was grinding the coffee too fine, but perhaps that is also a gasket symptom? I don't seem to get the dripping even when the grind is coarser.

Maybe you need to replace gaskets or other parts but IMO you haven't ruled out technique yet as a way to improve your results before looking for new parts. Added confirmation of this is the experts who would make money selling you the parts or doing the work telling you it's not necessary.

On the Bezerra my preferred shot is a ristretto. On the Cremina if I do a full lever pull I get about two ounces of coffee - nearly one ounce more than would be ideal. I get a nice dark mouse tail at first. About half way down the pull either the shot "blondes" or maybe that is the crema. In any case if I pull to the bottom I get an inoffensive shot but thin tasting, without deep coffee flavors and nowhere near the crema your pictures show. If I stop about half way I get some of the depth that I get on the Bezerra ristrettos, but little crema. I have had a couple of shots of Vivace Dolce that I liked as well as those that Vivace made on the Synesso at their shop - and there was some, although not a lot, of crema. My command of the descriptive terms is unfortunately pretty poor at this point.

The coffee at the time of testing with 3-4 day old (dated) coffee from Vivace. Should have been at its prime.

I think that I am applying about a 40 pound pressure on the lever. Resistance is steady after initial low resistance travel of perhaps 1/16 or so of the total distance. I haven't yet tried grinding tight enough to actually stall the system, so maybe I don't have the grind tight enough yet. However, the fact that I get no dripping when the lever is pulled up makes me a little reluctant to go any finer.

Grind finer! If you don't know what a stall feels like, or what a shot just on the edge of stalling but pushing through like cold butter feels like, you won't know what the ideal pull feels like. You've got arguably the best grinder going. Put it to the test. I grind 15 grams of beans per shot. (You haven't told us what your dose is. My guess based on your description of dosing and early blonding is that it is less than that.) A typical shot is two lever pulls, each one producing close to an ounce of rich, syrupy, crema-laden liquid. But watch the second pull for early blonding and pull the cup if it happens. If you're getting 2 oz with one pull and lots of blond liquid you need to grind finer.

The more I write, the more it sounds like the gaskets - I'm puzzled why the shop that looked at them thought they were good. If you agree will I be OK using the ones they manufacture - or is there a source for manufacturers gaskets that I should be looking for?

The tamper is a Reg Barber convex, designed for the Olympia. It seems to fit like a glove.

Well just to counter that thought, the more I read, the less it sounds like the gaskets. There is a simple explanation for why the shop that has probably seen bad gaskets is telling you to look elsewhere. Won't you be disappointed if you change the gaskets and there is no improvement in the quality of your espresso?

Distribution and tamping have been my biggest breakthroughs in improving my results. You mention not noticing a difference when you use different tamp pressure. This IMO is another indication that your grind is too coarse for tamping to have an affect. Grind closer to the ideal granularity for a golden rule shot and you should see that tamping pressure will matter.

[hperry]

Just a quick follow up - the problem is confirmed to be the barista. Spent a few hours with Dr. Jim and his wonderful Malabar Gold-based blend. Used my grinder. Got great crema and shots. Many thanks to Steve, Michael and Dr. Jim as I've tried to work this out.

Michael was right about the short dose. Largely solved that by stopping and tapping the portafilter lightly on the base of the Versalab while grinding. This allowed a considerable increase in the amount of the coffee in the basket. Distribution on the Versalab is good enough so it's largely tamp and go from there (would the large Elektra basket fit this portafilter. Would it be a good idea?)

I've tried to use the "loose portafilter" approach on the upstroke, but, at least at this point it's too many things happening at once. A smooth steady upstroke seems to work without breaking the puck.

Coffee was ground somewhat too fine. Backing off a little allowed proper saturation of the puck.

I still need to work on the tamp, but, I'm getting there.

I really have forgotten how long it took me to get shots I liked with the Bezerra. I did better with Dr. Jim coaching a bit, using all my "stuff," than I'm doing alone. But I at least know for sure where the problem is.

[espressoperson]

Glad to hear you're on the upward slope to improving your technique. IMO it's a slope that all of us who care are on forever...

...tapping the portafilter lightly on the base of the Versalab while grinding. This allowed a considerable increase in the amount of the coffee in the basket.

I use a sawed off funnel, just a little smaller than the portafilter circumference to catch all the grinds above the basket. This allows me to grind the full amount of beans at one time. Then tap the portafilter twice to settle the grinds a bit. Next slowly lift the funnel straight up. This heaps the grinds above the basket where they can be stockflethed into the basket. Then light tamp, tap to clear sides, full tamp, light finishing polish.