A complete newbie to lever machines (I have a Bacchi), I just picked up a Caravel and I have really a lot of questions about it for you experts.

First off, I wanted to take it apart to clean in well and probably change the gaskets, but I can't figure out how to detach the tank from the base. I took off little Caravel half-circle clip, but I don't see anything on the back of the tank that would allow me to loosen it.

Secondly, I pulled a couple of test shots just to see what would happen, and I found that the top of the tank (the part with the crest) pops up a little when I pull down on the lever far enough to feel resistance. Is this releasing pressure? Any idea how to fix it? I can put my hand on top of the crest to hold it in place while pulling the shot, but this is not very convenient.

Thirdly, although the couple of test shots I pulled were not too bad, the coffee was watery and had little crema. Is this because the gaskets are old/there is not enough pressure? The coffee was very fresh and ground fine -- the same coffee produces lots of crema in the Bacchi. The water heats to boiling with no problem.

Fourth, it looks like the filter basket that came with this Caravel is a single. How many grams of coffee should I put in it? The instructions I have (in Italian) just say "fill basket to top with one or two scoops of the included spoon and level off". The instructions also say "pull as many times as you like until you have as much coffee as you want". Looks like the manufacturer expected people to take a pretty laid back approach.

Fifth, anybody know where I might pick up a larger basket that would fit?

Here are some pics.

Thanks so much for any help.

gail wrote:A complete newbie to lever machines (I have a Bacchi), I just picked up a Caravel and I have really a lot of questions about it for you experts.

As seen in your last two photos, there is a small tab sticking up above the tank at the rear where it meets the frame of the machine. Depress this tab (push back, towards the frame / away from tank) and it will dislodge & allow removal of the tank/group. In order, I prefer to tear the machine down like this: remove lid from tank, remove handle from group (simply pull each side of the handle "out" away from the body), twist counter-clockwise to unlock the cylinder from the group and pull up & out, depress tab and remove tank/group.

My lid has never moved on it's own. I do not believe the contents of the water tank is under any pressure, so this is strange. Perhaps your piston piece is not twisted to be locked in place, so when you pull the lever down it may be pushed out of place? If this is the case, and your piston is not properly held in place, this is certainly to blame for your lack of crema and not pulling shots under proper pressure. The boiler tank is not pressurized, so the pressure for your shot only comes from the seals (holding pressure) and the pull of the lever to force the piston down.

Try to put as much coffee in your basket as possible. If you are choking shots, decrease dose or adjust grind slightly more coarse. I appear to have a double basket based on being able to easily fit more than 12g dose before leveling and tamping, but it appears to be quite small to the eye. I have not pulled too many shots on mine, but I prefer the shots where I fill & tamp, refill and re-tamp.

You probably have a better shot seeking baskets in Italy, but I believe Thijs of Brooks Espresso Machines is hoping to produce & sell baskets for Caravel in the future. He currently offers portafilters, gasket sets, and tampers at the very least - I think many of us are eager for the day his baskets will come.

I also have a "single" basket like yours, and I usually like to dose between 10.5-12 grams into it. It helps to use an Orphan Espresso dosing funnel and the "slap shot" technique, in which you thump an over-filled basket down a few times on a hockey puck (or some other similar surface) to settle down the grinds so that you can remove the funnel and tamp. This makes for very nice shots, on the borderline between ristretto and normale, with just a single pull of the lever.

Crema on levers is often a bit less than what you might be used to from pump machines. Crema itself has an unpleasant taste (when isolated from the rest of the shot), and is highly overrated as a sign of quality espresso, as you can get terrible shots with beautiful crema and lovely ones with very little. It is also as dependent on your grinder and coffee as it is on the machine. With a darker roasted, naturally processed coffee ground on my HG-one, I get tons of crema out of my Caravel; with a brew-roasted, wet-processed coffee ground on a bulk grinder, I get almost none at all. Either shot can be very enjoyable, so long as temperature, brew ratio, and grind size have been properly dialed in. My advice is not to worry about it too much, and just focus on the taste of the shots.

If the lever is giving you good, firm resistance, that is a sign that your seals are adequate; if not, then you should replace them with a set made by Thijs (his are much better than the sets sold by OE).

Thanks for all these suggestions. Based on the Francesco Ceccarelli website, I am pretty sure what I got is version 1.2. The shower screen is permanently attached to the cylinder and the edges of the base are rounded.

I was able to get the machine apart really easily -- thanks, I don't know why I didn't think of pulling the tab. I tried to move it right and left. The machine was actually quite clean inside, but I gave the piston and the shower screen element a quick soak in coffee cleaner anyway, put some food safe lubricant on the seals and then put everything back together and tried again.

I packed almost 12 grams of finely ground coffee into the filter and pulled another shot. It was quite tasty but had little or no crema and was somewhat watery looking. The cover is not popping up any more since I reseated the piston, but I can't tell if there is enough lever resistance because I have nothing to compare the resistance to. There is definitely some resistance when I pull the shot, but not what I would call tons of resistance and the coffee coming out looks watery (compared to what I am used to from the Bacchi). The piston seals and even the piston itself look like new, but the group seal looks dirty and worn. When I set up the machine to heat up the water, a little water leaks out the portafilter even with the lever in the down position, but once the portafilter is loaded with coffee, there is no leaking from anywhere whether the lever is up or down. So does that mean I need a new group seal only? What about that tiny o-ring in the bottom of the piston? I can't really see whether it is in good condition. Should I replace that too? I read on the Orphanespresso site that the little o-ring is a common source of problems. However, I am not too handy and as I said, the piston looks shiny and barely used, so I don't want to have to take everything apart again and replace the little o-ring unless I have to.

Is the water supposed to be boiling when I pull the shot, or is this a matter of personal preference and coffee selection? When the water comes to a boil the machine does not go off. According to the Italian instructions, that means I have to adjust the thermostat. There is a button for that but I am not sure it is working.


Anybody have any experience with Francesco Ceccarelli's replacement seals? Since I am in Italy, getting gaskets from him would probably be faster and cheaper.

Thanks again for any suggestions.

^ Just guessing/reading between the lines...but #1 it sounds like you might need a quality grinder capable of making precise and consistent grind adjustments. What grinder are you using or are you purchasing pre-ground coffee?

Generally there is about a 9 degree F temperature drop from the water reservoir to the piston group (dependent upon the ambient air temp). So, assuming at/near sea level, 212F - 9 = 203. This would be a little on the high side especially for medium to medium-dark roasts...but easy enough to adjust by pulling shots when the tank water is a little lower temperature.

Thanks for the information. I don't buy pre-ground or even pre-roasted coffee. Right now I am using several vintage manual grinders -- I pulled one shot using a Gesto Record and one using a Dienes 623. I roasted the coffee myself with a Coffee Tech Baby Roaster. I roasted it a little into second crack and used it about 6 days past roast. Maybe I need to grind finer? I was using the same kind of grind that works on the Bacchi. When I use the same beans and grinder to make coffee with the Bacchi, it comes out virtually 100% crema. I will measure the water temperature in the Caravel tank next time before I pull the shot to get it in the right place. The Bacchi temperature control works in a different way.

gail wrote: Anybody have any experience with Francesco Ceccarelli's replacement seals? Since I am in Italy, getting gaskets from him would probably be faster and cheaper.

They appear to be about half the price of Thijs' seals, Thijs is offering custom made silicone seals rather than standard old rubber types. Given the number of people who seem delighted with the silicone over rubber options, I went with silicone myself.

Since there's plenty of space within the base (and my machine came with a broken thermostat microswitch), I set out to make a completely internal PID controller for it, with no exterior modifications and using the original knobs and power switch. At this point, I still need to repaint the base, tune the PID, and transfer the circuit to something more permanent. Most of the coding is done, but I'll probably implement a simple two stage temperature control, where during initial power on, the heating element is turned on all the time, and the PID takes over only when input temperature is within, say, 10% of the target. That should help it heat up a bit faster without compromising temperature stability once it's at temperature.

I'm using the open source PID library for Arduino to control an eBay solid state relay, and temperature readings are read by a digital DS18S20 temperature sensor which is easier to integrate than a thermocouple, and adequate for the purpose. I had planned on mounting the sensor near the grouphead (right where the VAM letters are), but it turns out to be too thick and prevents the boiler from locking on (hence the yellow masking tape holding the boiler in place). I'll probably end up mounting it to the rear instead with some Kapton tape, or maybe try to sand down the sensor cover, since I'd ideally like the sensor to be as near the group head as possible.

Instead of adjusting the thermostat, the knob works like a Linea Mini-esque temperature adjustment and goes from 88 to 98 degrees C. That way, I can tweak the brew temperature to taste without a temperature readout, while always staying inside a reasonable range. The original knob will be connected to a potentiometer, and the output of which is mapped to the temperature range. Whenever the setpoint is updated, the new value is written to EEPROM so that the setpoint isn't reset to default when the Caravel is powered off.



edit: also, it took me a while to locate a high temperature hammertone paint that matches the original. The hammered effect ended up spraying on really unevenly, so I'll probably have to suck it up and find a powdercoater to redo it. I thought about going for a smooth finish, but after I sandblasted the base, it was obvious that some sort of textured paint will be necessary. The casting is pretty rough with a bunch of imperfections, and smooth paint will make all the flaws and rough tool marks really obvious.

So the good news is that by playing around with the grind and tamp, I was able to pull a shot with pretty good crema.
(In fact, during testing I also choked the machine a couple of times, so maybe the seals are good after all.)

The less good news is that the on-off switch is no longer working. When I first got the machine, the on-off switch was working well, but the heater did not turn off when the water came a boil. The water just kept boiling and I turned it off using the on-off switch. I read in the Italian instructions that to make the machine turn off automatically at when boiling, I should tighten the thermostat regulator (the little screw-like knob on the top of the back). I did this, and the result is that the water keeps boiling anyway and also the on-off switch does not turn the machine off any more. So I loosened the thermostat regulator knob, and the on-off switch still does not work. Now I have to unplug the machine to turn it off.

However, I noticed that if I push the on-off switch in, the machine turns off (and the thermostat regulator screw pushes out). But as soon as I let go of the switch, the machine turns on again.

I read many pages back about a possible fix for this but I did not quite understand the explanation and in any case I have a slightly different model. Is this an easy fix or is it better just to plug in and unplug the machine? Is there an easy way at least to make the on-off switch work again?

Thanks.

Spiffy,

If you start making PID kits for the caravel, I'd be interested! Keep us posted on how this project turns out. I like the idea of keeping everything original on the outside, but making the temp adjustment modern.

Great work.