Wow! I blinked for too long and you went and made an espresso machine! Super, super cool!

Haha! I've stalled progress a bit lately....I guess once things start getting finalized there's not as much to do.

My to do list is:

• Add Steam TB and controls
• Take a video of predicted temp getting hit by Scace (this is very repeatable now within about 0.5F)
• Calibrate Scace so results can be compared
• Take a few more temp profiles with the Scace at different temp offsets.
• Post some steaming tests of how the TB performs so others can decide if it will be good enough for them, or if they would need a boiler to get steam performance they want
• Post a full parts list once Steam is finalized

Anything else people want to see welcome to request. Work has been a bit busy lately, but I'm sure at some point I'll get it done.

After the above list I plan to look into what it will cost to finalize my frame, maybe wrap it in a hammered copper shell, and get a drip tray fabricated. Basically just the visual wrap up.

Only latest change had been mounting the steam wand.

I was beginning to wonder if you had forgotten this project.

For sure not! I've been using the machine several times a day everyday for a while now...my BDB is really the forgotten machine.

But I do need to make progress on it, hopefully this week will have something cool more to share.

That has my attention. This project has a great deal of appeal to me as you end up with a custom built machine with at least some money left over.

Glad to hear, I'm up to around $1,100 in cost of parts with the steam wand. Again once I finalize steam and make sure no other fittings are needed, I'll plan to release my parts list and sources. Half of that cost is of course the group itself, so price fluctuation to the Euro would make a decent difference.

Here is a quick video showing a fully warmed up shot. I'll be doing more formula tuning, and will try to hit correct temps when group head temp is further from the set point. But right now it's working very well as a guide at lower temps, and very accurate once fully warmed up.

EspressoForge wrote:Glad to hear, I'm up to around $1,100 in cost of parts with the steam wand. Again once I finalize steam and make sure no other fittings are needed, I'll plan to release my parts list and sources.

That is an amazing deal! Plus all the tinkering and customization is a bonus!

The builder gets to do all the tinkering and customization which is a major benefit in this project.

Steam TB hooked up hydraulically. Hopefully can connect electronics this weekend, after that should be easy to program and test. I have another spare needle valve I'm using to control the flow of steam, but I bet a less precise valve could be used.

So I've finally got the steam side all connected and working.

Control scheme is basically 3 modes, select-able by a couple switches:

1. ON - brew priority - in this mode, brew TB is pulsed as normal, extra capacity is given to steam TB to warm-up to 260F. Both elements are never on at the same time. It takes about 3-4m for the steam TB to heat up once the brew TB has gotten up to temp.
2. ON - steam priority - brew TB is turned off, steam TB setpoint increased to 300F, factory setting is 329F (165C) though I'm not sure such a high temp is required.
3. OFF

I'm still playing with the setpoints and control scheme. Good news is that the TB has a lot of room for both flow and temp adjustment. I have a needle valve on the input, and obviously the valve on the output. For now my general observations are that the steam starts out wet and at high pressure, but dries out if you purge it for about 5-10s. It seems to steam faster than my BDB, but for now my milk results with a 4 hole tip aren't great. I've only tried once, so maybe it will take adjusting the temp or flow rate or valve (and likely improving my steaming skill)...or some combination of those.

Compared to a large boiler, my initial impression is that the TB will never be amazing. I'm not really much of a milk guy, so I think for me it won't matter, but I'll try to get some timing of how long it takes to heat cold water of different amounts, and others can decide if it will be good enough or not.