My Bezzera BZ99S project machine

[HolyGrounds]

I am looking to start restoring espresso machines as somewhat of a hobby. It seems however that there are not too many guides out there for people to dive into it with a low starting knowledge. Do you have any recommendations as to where I can get started? I now have two machines to tinker with. The first is a La Scala Butterfly with a Lever. And the second is an Expobar Office Control 1gr.

[Gronk]

This video is a bit of a cautionary tale of Gaggiuino https://www.youtube.com/watch?v=5-PWW3dbh1c

Actually watched this this morning. He went straight to black pill instead of or Arduino to black pill. Much less documentation around black pill.

[dischucker]

This video is a bit of a cautionary tale of Gaggiuino https://www.youtube.com/watch?v=5-PWW3dbh1c

[Dimal]

Lots of fun ahead in that little pile of goodies...

Mal.

[Gronk]

Well look what turned up more than a month early. I have two weeks off and a lot of gaggiuno hardware.

[Gronk]

The back is satin black, now. Black and white is a whooole lot better than white on white.

Still waiting on Arduino parts. I might start by making a screen mount in preparation of receiving the parts.

[Gronk]

Update: I bought all the components for the gaggiuno base plus pressure. That will allow for automated profiling.

In the meantime I'm going to look for alternative switches and a nice was to install barista lights (the grill either side of the group head isn't open enough to let significant light through).

[Gronk]

So many great ideas! So much to unpack, so I'll address what I can.

the drip tray has a small crack, but generally warped. I'm not too sure what my long term plans are.

The dimmer mod controls the voltage to the pump so you can get control over the flow.

I have T'd off after the diaphragm and have a capillary tube going to a gauge, so have brew pressure sorted, no need for opv thanks to variable voltage

As for the water, I should be able to bleed off pressure via the steel wand, albeit more slowly.

Thanks for the heads up on the switches. The current ones are a bit of an eyesore!

I think the Arduino is the way to go. I think it'll allow for a lot of flexibility.

[EspressoAdventurer]

Hi Gonk Im no IT Gu=ru So I'll leave that to others to provide input.
Ive had a BZ99 and always remember it fondly. Ive said it here before ...it may no longer be the latest and greatest But its like a Commodore its rock solid, and parts are available at every second milkbar on evry second cnr. And rewards good barista inputs !

Obv extent of the mods all depends on real estate (space) available. Im trying to visualise how much space is free Or how much effort you want to go to to create more.

So Don' know what the dimmer mod you referred to is....pressure or flow control of the pump ? Or both ? Y / N ?

Mods suggestions -
- Plastic drip tray RH back cnr where the brew path solenoid valve exhausts, the heat of the water cracks the tray.
This is a common report here from many years ago, A metal shield wouldn't be difficult to fabricate.
- Barista lights ...Yes.
- Front panel - the OEM switches / and lights are something on my list. Jaycar have anice chrome & backlite numbers (similar look to one of the Breville's.. Oh dear), whether the diameter matches a straight swap out refit ? IDK...
- The front panel could house the Arduino screen in centre.
I'm running a Super Lever E61 ATM and have manipulatated the open / close of the inlet / exhaust valve together with / seperated the pump switch activation to give some play room over - wetting the puck / slower ramp up of pressure.
- This you could experiment here with by seperating the single brew button control into 2 switches (temp) to see if / how it works on a 99.
- Also as the BZ99 runs a Solenoid - so therefore no Gicleur, try slowing the flow rate ( what is it currently?) from lets guess at say 8ml / sec currently down to 6mls / sec, or even try a lower rate 5 or 4.
If the solenoid orifice can't be manipulated...maybe a downstream Gicleur could be added.
On most E61 the Gicleur size is directly related (orifice) size vs the flow rate ......0.X mm = X.0 mls / sec flow rate.
- An upgraded OPV with an external access point for experimenting with a lower max brew pressure rate.
- Tapping the Grouphead running a capilliary tube for a Brew Pressure gauge.
- K type Temp Sensor at the Grouphead for an accurate Temp gauge, or run it of the Arduino screen for adjustable temp setting.
- Look into the BZ10 Temp heat cartridge and install for quicker heat time / easier temp control with the Arduino controller.
- (Optional) Non crush style Steam and Hot water Valves. Swap Swap out Swap In off one of the hihger level Bezzera models.
- Route the OPV return line into an exhaust valve at the drip tray rather than feeding back into the water tank.
Reason being found it contributed to (slight) contamination constantly in the water tank.
PS with the hot water outlet disconnected....how do you drain / bleed off water from the boiler ?
sorry to say but not a fan of that being disconnected. See above with creating more front panel real estate.

GL with it Gonk hope to see how you progress.

[Hornetb]

Yes, the soup of threads caused me a lot of messing around. I have a lathe so some parts I made or adapted/changed but it was annoying.

Yes, unfortunately there is almost no info on that build but it is lovely and the programming is lightyears beyond my ability. I don't need the clock though as my scales can do the work but it was a fancy feature that I liked the look of.

[Gronk]

I'm sure you've seen this but I love the execution on this one: https://www.youtube.com/watch?v=iUYz...channel=Jubbel

I'm very familiar with this, but there is almost no documentation about it.
I'm leaning towards the gaggiuno to get more out of it.

The BZ99 is annoying in that it uses a mix of metric and BSP, and the metric is a thread that is essentially non-existent - I had to get a bit creative (like making my own adaptors).

I have all the parts sitting in my cart. Maybe I should just do it while the sales are on. $6 savings!

[Hornetb]

I'm keen to follow along with this. I've got a BZ99 that I'm planning very similar things. I quite love the machine. I've done the rebuild and now getting to the fun bit of customising and adding some features.

I'm sure you've seen this but I love the execution on this one: https://www.youtube.com/watch?v=iUYz...channel=Jubbel

I want a shot timer but don't like the commercial examples I've found (other than the Dotshot but I don't think that is available anymore and the price is ridiculous). I've also been having a tinker with some Arduino and lcd screens but not made much progress on that.

Planning on timber panel, custom feet, gauges. Might even give it some lean towards the Linea mini styling which I quite like.

So really I'm in the early stages but the machine is sound and working fine but currently back in pieces again as I formulate where to go with it.

Good luck and keep us updated.

[Gronk]

Take a look at the Gaggiuino project. The Arduino code is already written (open source) and I'd guess you'd only need to implement the features you want...

They've made this so easy with the hardware links and everything.
it's about $120 for base plus pressure control, so I'm wondering if I should do this anyway.

[Gronk]

Well done Gonk.....In fact you n me might share some dna.
for instance I luv a 'pimp my espresso machine' thread.
Ill share some thoughts / ideas as soon as I have further free time.....

Please do. This is not my daily, but I'm a Bezzera fanboy (daily is a matrix).
there is another "pimp my BZ99" on here, but I am going a different direction.

[EspressoAdventurer]

Well done Gonk.....In fact you n me might share some dna.
for instance I luv a 'pimp my espresso machine' thread.
Ill share some thoughts / ideas as soon as I have further free time.....