Sounds like you are about where I am with steamed anything in good coffee. Still good progress towards the final product.

Greetings to all,

I've been following this build for a couple of weeks now.
I read the 500 odd posts in one sitting when I came across it.
Really great work!

I suspect that your steaming troubles may be alleviated by changing the nozzle on the wand.

I have an Innova Dream with some variant of the Thermoblock inside (I haven't taken it apart to see which one yet). I used to use it at my office to make between two and eight cappuccinos a day (sloooooow) before I replaced it with a commercial machine. After about a year or so of practice and a minor modification to the steam nozzle of the Dream, I found I could make pretty good micro-foam, denser than other commercial machines that I've used. However, by the time the milk itself was barely hot enough, there tended to be much too much foam. The single Thermoblock in the Dream obviously has to do double duty and so has to be thoroughly purged of water before it starts producing steam. Even after purging however, the steam remains very wet.

The steam wand on the Dream consists of a nozzle with a ~1mm opening inside a 25mm long sleeve. The sleeve has a very small hole about half way up the side which creates a Venturi effect that sucks milk into the steam jet exiting the nozzle. The modification I made was simple to remove the sleeve and to use the nozzle directly, surfing just below the surface of the milk. The sleeve makes it easy to stretch the milk, but does a poor job. The nozzle on its own is tricky to get right, but makes great dense foam.

My suspicion as to why you are having difficulty with the four nozzle wand is that there just isn't enough volume of steam being produced by the TB to generate the flow rates required to power four nozzle openings. After all, the wand you have is designed for a machine with a four or five liter boiler about a third of which volume is pressurized steam! An easy test for the theory would be to crank up the TB to full power and block up three of the four holes on the nozzle.

Bidoowee

bidoowee wrote: I suspect that your steaming troubles may be alleviated by changing the nozzle on the wand.

Thanks! I have planned on that, in fact another builder has said that a 2-hole tip from Chris's Coffee is working great:
https://www.chriscoffee.com/2-Hole-Stea ... 0980sv.htm

I plan to test today, this weekend was a busy one so didn't get much done with coffee.

Once I have things working well with steam I'll plan to do some cold water tests and see how fast it goes objectively. Then compare against my BDB for milk texture. Will just be a basic comparison, I'm hoping at least to get a similar power and texture as I'm happy with BDB steaming personally.

Plugging up 2 holes is working very well, I'm probably going to buy that 2 hole tip and move on. I've been needing to tune the PID for steam, as it is now I just turn on the steam side, and switch it off if I'm not going to use it right away. Keeping brew priority works very well to keep brew TB at temp, and heat up steam TB only when the other isn't on.

I also have a bit more tuning of my formula and Scace tests, but overall I'm feeling that I'm 90% there.

Now I just have to decide if I want to tear things apart again and add some cartridge heaters to the aluminum plate or not. In some ways, after seeing the LSM lever group has space at the back for cartridge heaters, I wish I had gone with that group as I feel it would have been more flexible and possibly let me not need a big metal plate to heat up. But as it stands now, I'm happy with the way this one has come together, and with my sort of HX adjustability in temp. It's very fast to adjust temp for a shot, so I feel that goal has been met relatively well.

I wish heat up was faster, but at around 30-45m it's not bad. My pour over machine likely will be still used when I want a shot in under 5 minutes and if the big lever isn't already heated up.

There's still a lot of missing aesthetic potential in a housing.

I suppose at the minimum you could bedazzle it.

Fully agree, but since I'm not an artist, I fear that anything I come up with would look pretty terrible. I'm more apt to leave it the way it is. I'm sure you saw Jorian's build for an idea on what is possible if you build a custom frame.

Either way I'll be publishing my current frame design and dimensions, so with open source anyone is welcome to come up with an awesome case design.

I've just spent hours reading the entire and brilliant thread.

EspressoForge- You have shown incredible patience with several instances of opinionated negativity and with parts mis-matching. I congratulate you on your build, hats off to your skills and thorough documentation along the way. Its great to see that your lever machine does function well. I think it looks great without an enclosure.

I too was hoping to see the cartridge heaters in the back of the group as another method of heat assist. I do think that this would bring a faster heat up time and better adjustability over the large metal block.

I also liked the idea of a small boiler as a steam engine- the silvia that was mentioned produces enough steam, and its small enough to bolt up to a frame of your size. I'd even consider it as a separate machine, a stand alone steamer.

I hope that this note of encouragement helps bring your project to completion. At the onset, your goals were fairly lofty, with group purchasing power and with a DIY kit type of assembly. It certainly caught my Perhaps just posting a list of links and info on where you were able to obtain the critical parts, with costs and maybe lead times would allow bystanders to fathom the barriers with this project.
Not everyone is able to sketch out a wiring diagram on a napkin, or successfully tune several PIDs, or even tap into a 1/2 inch block of aluminum. Everyone has their own set of skills, and tools, and know how, and I know you set out to make this project achievable to most home users.

All in all - awesome job. I want to make my own, and its projects like this that make it seem do-able.

thanks
p

Hi Porter! Thanks, yes I definitely haven't given up on this project. Lately my priority has shifted as I'm using all free time to get out pre-orders.

Once I'm free again my plan is to tune the steam side a bit more and determine what changes hydraulically or practically need to be done. I'm pretty happy with the brew side right now, but it may benefit from moving the needle valve around.

As mentioned I was planning to post my full plans with parts and build once I have it finalized and I'm 99% sure I won't change anything. I guess some fun is changing things now and then, but there has to be a line in the sand somewhere!

Time is starting to free up, I see the light at the end of the tunnel. My current plans are to move to a different configuration that Thomas has implemented with more active heating of the group and disconnecting the TB.

You can read about his build here:
La San Marco Open Source Lever Machine

Basically I'll trim down the large aluminum plate I have and sink some cartridge heaters into it.

I also have some plans on the steam side, and may just move to a Silvia boiler to give more reliable and simple steam output. The TB certainly has a lot of pressure, but the problems it suffers are too much pressure and not enough steam volume as a reservoir. There may yet be a way to tune it, but I would advise anyone who likes steam a lot to just go with an appropriate sized boiler for how much they plan to steam.

I like that approach much better as I steam nothing ever so that eliminates several parts I do not use.