Here's the close up of the brew path.



The water entry should be obvious, then it travels up, thru the bright green section, thru the filter screen (transparent grey), down thru the gicleur (yellow), into the valve section (blue). The valve is shown closed.

When the orange cam rotates up (it's attached to the lever), it pushes up the valve seal (yellow) and brew water floods the cam area, then goes up towards the infamous allen screw. (Now it should be apparent why it's there as well. It would be hard to drill around that corner.)
Then down toward the dispersion disk.

Please pardon the jpg. I resized it and added the text with free software and it mangled some areas (particularly the reds), but you get what you pay for.

Also pardon my part names. Not sure I'm using the proper names, what I'm talking about should be clear though (I hope).


Anyway, does that make sense? Are any parts of the picture unclear?

Lemme know.

ciao

lino

I see said the blind man.

lino,

I created a crude thermal model using your pictures. I am sure someone has done this, but I thought it would be fun to try. The results show a 10 degree (F) drop to the tip of the group head. Maybe there should be a bigger area hogged out like the patent drawing has shown! But how would you machine it? Has anyone measured temperatures on the exterior of the group. I do not have a thermocouple, but would like to know if I am in the ball park.

The most difficult thing for this type of thermal model is in calculating the convective coefficients (hc) for all of the surfaces. I have a spreadsheet for this that I have used before for electronics. This is also the greatest source of uncertainty. You really have to run the model once and then iterate, which I haven't done yet.

FYI- I used Designspace for the FEA, and Inventor to create the model. For a steady state thermal model like this, FEA is much simpler than for stress analysis- every node has only one degree of freedom.
My geometry is not very accurate- I scaled your drawing and took some measurements off my Zaffiro. I assumed free cutting brass for the E61 material properties. Is this correct?

Also, I assumed the water to be 200F, and stagnant. What is the flow rate of thermosyphon?

Regards,
Bruce

http://isotherm.blogspot.com/

Great work! Is the mushroom you mentioned in the earlier post the yellow 'valve seal' the input for the HX?
Geoff

lino wrote:The water entry should be obvious, then it travels up, thru the bright green section, thru the filter screen (transparent grey), down thru the gicleur (yellow), into the valve section (blue). The valve is shown closed.

crudo20 wrote:Great work! Is the mushroom you mentioned in the earlier post the yellow 'valve seal' the input for the HX?
Geoff

The two HX inputs are the threaded holes on the right side of the pic with the black background. The "mushroom" is the is the part shown in red, that's not my name for it, that's the official name. So the thermosyphon moves water around in the ring shaped cavity outside the red part. When the valve is opened the water goes up first, then down the center.

Did I make better sense? I have a bad tendency to explain things as though you already knew what I was thinking...

ciao

lino

Below is a picture of the "mushroom" from my espresso machine:



It's easy to unscrew and gives you an indicator of the scale buildup.

With that and Dan's picture, it really makes sense, thanks! I didn't understand that the HX water becomes the brew water. I had thought the HX was only for heating the head and brew water was separate. The visual diagrams really help bring all the info in Dan's HX love article together. Too bad I don't have a wrench big enough to get my mushroom out so I can start tinkering...

lino wrote: The two HX inputs are the threaded holes on the right side of the pic with the black background. The "mushroom" is the is the part shown in red, that's not my name for it, that's the official name. So the thermosyphon moves water around in the ring shaped cavity outside the red part. When the valve is opened the water goes up first, then down the center.

Did I make better sense? I have a bad tendency to explain things as though you already knew what I was thinking...

ciao

lino

Ozark,

Park Tools USA makes a 36 mm closed-head wrench (PARK HCW-4) for working on bicycle cranks and bottom brackets that fits perfectly on the large nut attached to the E61 'mushroom' of my Andreja.

http://www.parktool.com/products/detail ... item=HCW-4 (I have no connection to Park Tools, other than using their tools on my mountain bikes.)

lino wrote:Here's the close up of the brew path.

<image>

The water entry should be obvious, then it travels up, thru the bright green section, thru the filter screen (transparent grey), down thru the gicleur (yellow), into the valve section (blue). The valve is shown closed.

When the orange cam rotates up (it's attached to the lever), it pushes up the valve seal (yellow) and brew water floods the cam area, then goes up towards the infamous allen screw. (Now it should be apparent why it's there as well. It would be hard to drill around that corner.)
Then down toward the dispersion disk.

Please pardon the jpg. I resized it and added the text with free software and it mangled some areas (particularly the reds), but you get what you pay for.

Also pardon my part names. Not sure I'm using the proper names, what I'm talking about should be clear though (I hope).


Anyway, does that make sense? Are any parts of the picture unclear?

Lemme know.

ciao

lino

most impressive

kikuchio

Awesome, as beautiful in the inside as the E61 is on the outside.

Thanks for the great pictures.

Bob