• Electronics Enclosure

    Tobias • 08/08/2023 at 13:37 • 0 comments

    As you can see in that last picture of the inside of the 800ES/B, there's not a lot of free space, and certainly not enough to cram all of the Gaggiuino control components inside. I wasn't entirely comfortable just putting the control box on the outside, as it includes mains-voltage components. So instead I modified the standard Gaggiuino control box so that it could be mounted inside an off-the-shelf project box. Actually, I just used the clear lid of the project box, but the electronics are encased in a tough and fully insulated case.

    Here's the enclosure that I used: https://www.jaycar.com.au/sealed-polycarbonate-enclosure-with-mounting-flange-171-w-x-121-d-x-80-h-mm/p/HB6223. This comes from a local Australian supplier, so I'm not sure how available it will be to everyone else. I would actually recommend editing the OpenSCAD file to match whatever enclosure you can find

  • Safety First!

    Tobias • 08/08/2023 at 04:16 • 0 comments

    There are a lot of different versions of the Gaggia Classic, but the versions I find most interesting are those sold in Europe. As far as I'm aware (and I've actually never owned or used a Gaggia machine) the European versions all include a standby timer, essentially a device that will automatically switch the espresso machine off after a set amount of time. A steam boiler is an inherently risky piece of equipment - in the very best case leaving it switched on for a long period will waste a lot of electricity, but the worst case could vary from burning out the heating element, to causing a fire, or even causing a steam explosion. Unlikely, yes, but conceivable. There are safety features to prevent this like a thermal fuse and pressure release valves (I don't know for sure if any particular espresso machines have PRVs), but I can't see any reason to forgo the additional safety feature of automatically turning off... before anything like that can go wrong.

    The Breville 800ES/B had this feature built into it's electronic circuitry, but this was all removed, so it's a feature I had to add back in. To do so I used this time-delay relay: https://www.aliexpress.com/item/32881831418.html?spm=a2g0o.order_list.order_list_main.94.54861802tmytIp. Among it's many functions it can be configured to close the relay when it first receives power, then automatically open the relay after a configurable amount of time between 1 second and 10 days. Correctly wired this provides the automatic shutoff feature perfectly.

    In this picture you can see the relay inside the coffee machine. It's mounted to a 3D-printed frame that also mounts the solid-state relay and a WAGO-style terminal block to distribute power. This in-turn is mounted to the screw bosses that were used to mount the original control PCB to the machine's chassis

  • Disassembly - How do I get this open?

    Tobias • 08/07/2023 at 07:21 • 0 comments

    Unlike the Gaggia espresso machines, the 800ES/B certainly seems to be made with a lot of extra panels, plastic pieces, and screws in awkward places. To be plain, getting it open is a right pain.

    I can't recommend this website strongly enough: https://siber-sonic.com/appliance/breville.html. It contains a huge amount of detail on how to disassemble every part of the 800ES/B, as well as really useful information on wiring and troubleshooting electrical issues with the original 800ES/B

  • Breville 800ES/B vs Gaggia Classic Pro

    Tobias • 08/07/2023 at 06:59 • 0 comments

    So, what's the difference between the Breville 800ES/B and the Gaggia Classic Pro that's normally used as a the basis of a Gaggiuino conversion? Once you remove the 800ES/B's control electronics, there really isn't a lot of difference. Like all espresso machines, there's really just a boiler and a pressure pump, so wiring these up according to the Gaggiuino documentation is easy.

    There is one significant difference - the 800ES/B doesn't have a solenoid valve that controls flow between the boiler and the grouphead. Instead it has a manual valve that you have to twist to the left to brew and to the right for steam. While it might seem like this creates additional steps to brew (open the valve _and_ press the brew switch), happily the valve is set up with two microswitches that tigger when the valve is opened to the left or right. We wire these microswitches up in parallel and use them as the brew switch.

    The other difference is how we have to mount the thermistor to the boiler. Unlike the Gaggia, there's no convenient M4 threaded hole that we can screw the thermistor into. Instead, we'll have to use a thermistor with a ring mount, and attach this to the boiler using one of the screw holes that previously held the thermal switches. It's important to use one that is ungrounded. I'm not sure exactly why, but I know that the first thermistor I tried was grounded and had huge issues with electrical interference. Here's the correct one I used: https://www.aliexpress.com/item/1005003664282170.html?spm=a2g0o.order_list.order_list_main.37.21ef1802TWlqg9

    Above is a picture of the boiler. On the left is the thermistor with the metal braided cable. In the middle is the thermal cutout fuse with the brown wires. On the right is one of the original thermal switches. This is not used by the Gaggiuino system and is completely disconnected.

    One final warning - the thermal cutout fuse needs to remain wired into the circuit in such a way that if it blows the boiler will not be powered.