Building my own espresso machine - Page 2

Need help with equipment usage or want to share your latest discovery?
bgn
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#11: Post by bgn »

have you noticed the home made machine posted recently on the thread "post a picture of your set-up"?

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Bluecold
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#12: Post by Bluecold »

roastaroma wrote:One configuration I have not yet seen is a double-boiler spring lever w/58mm PF and thermosyphon group head.
Double boilers aren't suited for thermosyphons. Thermosyphons work on a temperature difference, something you don't want to have with a double boiler configuration.
LMWDP #232
"Though I Fly Through the Valley of Death I Shall Fear No Evil For I am at 80,000 Feet and Climbing."

ferrum (original poster)
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#13: Post by ferrum (original poster) »

First:

THANK YOU ALL for the replies!!!


Yes I've noticed the other "home-built" machine by now... different than what I aim for, but nice ;)


to: djmonkeyhater
yes, done that a couple of times ;)
and yes, it helps...
and actually, your design idea rocks! (I might go for something in that direction...)

gyro:
thanks for the link!


I'll keep you guys up to date on this... might take some time... but I'll get there... photos of course too (maybe I set up a dedicated gallery on my website, once I get started and a small "blog")

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HB
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#14: Post by HB »

Bluecold wrote:Double boilers aren't suited for thermosyphons. Thermosyphons work on a temperature difference, something you don't want to have with a double boiler configuration.
The Expobar Brewtus managed to make it work.
Dan Kehn

akallio
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#15: Post by akallio »

Bluecold wrote:Double boilers aren't suited for thermosyphons. Thermosyphons work on a temperature difference, something you don't want to have with a double boiler configuration.
People say this quite often, but it would be nice to hear practical arguments to support it...

JimG
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#16: Post by JimG »

Bluecold wrote:Double boilers aren't suited for thermosyphons. Thermosyphons work on a temperature difference, something you don't want to have with a double boiler configuration.
There is enough temperature stratification within a vertically mounted brew boiler to make it work. Seems to be effective on my Alexia.

Jim

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Bluecold
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#17: Post by Bluecold »

HB wrote:The Expobar Brewtus managed to make it work.
Oh yes, it works on the brewtus. If you follow the flushchart, which involves using a stopwatch (akallio, this is the practical argument).
I'm not saying it's impossible to use a thermosyphon with a double boiler. It is entirely possible (Doubledomo, Alex duetto, Brewtus..). The group will just run a bit cold. Or the boiler will have to run a bit hotter (7 degree offset with the brewtus). And then you need charts and stopwatches. But the point of a double boiler is to keep the boiler and group at brewtemperature and not having to worry about temperature.
I just can't bend my mind around it why the mfgs jump to all sorts of hoops to fit 2 boilers in a compact package and then bolt on a E61 because it was just lying around and looks pretty.
LMWDP #232
"Though I Fly Through the Valley of Death I Shall Fear No Evil For I am at 80,000 Feet and Climbing."

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hbuchtel
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#18: Post by hbuchtel »

I built this espresso machine (no laughing at my manufacturing skills please ;) )

The 'brew-temperature HX' design makes temp control really easy while keeping the brew water fresh. Because the only high-pressure area is in the HX, the boiler can be made using very thin (inexpensive!) steel, similar to a tea kettle.

Hope it gives you some ideas!

Regards, Henry
LMWDP #53

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cannonfodder
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#19: Post by cannonfodder »

E61 group equals thermosiphon even with a double boiler. The group is not attached to the boiler and needs heated to brew temperature. A double boiler with a directly connected group, or saturated group like the LM's would not need the thermosiphon.

You could build a machine without a lot of issues. Most of the e61 group machines use off the shelf parts. There tends to be very little difference between e61 boxes. You could purchase the parts from any parts vendor, make a case and bolt them all together. The expensive parts would be the boiler, group head and level box (brain box) for the system. You would have a hard time machining a group head without having one to take measurements off of.
Dave Stephens

decaf_Ed
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#20: Post by decaf_Ed »

Daniel,

It sounds like you're starting a fun project. It also sounds like you could have a lot of competing ideas, and you may also have competing requirements. The tradeoffs on single vs. dual boilers, and thermosiphons vs. saturated groups could come down to something simple, like how much, or how little, flush time do you want? If you're not obsessed with "fresh" water, It's easy to to get flush time down to zero if you don't care about looks, just keep the group heated, either with water (saturated group) or electricity. If you want the look of a fully-exposed group, neither of these may be desirable. I've tried the latter (heating the group electrically) and it's technologically a very easy and effective (+/- a few tenths of a degree) route, and probably the best way to accommodate variations in ambient temperature and wind speed (vs. thermosiphon or saturated group). With a little insulation, less than 100 watts (probably less than 50 after reaching target) is needed. Good looks is the department where the artist is needed.


My attempt at making the looks tolerable:


Good luck! And I'm sure there are very many readers that are extremely curious to hear about your decisions and progress.
-Ed