HomeRoast Digest

Topic: To go or not to go rotary pump? (5 msgs / 149 lines)
1) From: Obrien, Haskell W.
So guys, I have an ECM Giotto.
I happen to have a new procon rotary pump and motor just sitting on my
basement floor.
Is it worth going rotary over the vibration pump?  What are the
advantages, really?
What sort of parts would I need?  Hose type etc...

2) From: Jim Mitchell
Haskel -
It's not a particularly difficult conversion - especially if you're a rude 
and crude hot-rodder like me....
I just followed the output line from the Ulka vibratory pump to where it 
joined an obvious 'intake manifold' and patched the output of the Procon 
pump (mine uses 3/8" standard fittings and 40" braided pressure hose) in 
there using a 3/8" NPT Male (National Standard Thread) to 1/4" BSPP (British 
Standard Parallel Pipe) female adapter. I went through a stupid search to 
find these parts - but both Espresso Parts NW and Chris's Coffee are 
supposed to stock them.
I then used the existing power wires to the Ulka pump to control a 20 amp 
SSR (possibly overkill to use a solid state relay, but I had one handy) to 
feed power to the Procon pump.
Note that the pump is controlled by two devices - a microswitch behind the 
E61's lever (for pouring shots), and a lead from the machines's control box 
(for auto-filling the boiler).
I just dropped the Procon's input hose into a 5 gallon Mineral water jug, 
the pump appears quite happy drawing about a 30" head - but I did have to 
prime it prior to final installation.
If your machine is a pour-over style, you may need to jumper the internal 
tank's 'Out of water sensor' to ground. On my Isomac with a Giemme 
controller it was easy to jump from pin 12 to pin 15 to ground this sensor.
Since this conversion is fairly simple, and easily reversible, it's worth 
your while to try for yourself - my take is that the taste differences are 
fairly subtle - your varietals will retain their unique characters, but that 
there was more 'clarity,' more fullness, and more depth to the coffee. Plus, 
now I get to play with pressure as well as temperature variables.
I've post a number of threads over at the Home-Barista Espresso machines 
forums about this project - they might be useful too.

3) From: miKe mcKoffee
I can't say whether it'll be "worth it" to you or not, and haven't had a
direct same machine vibe vs rotary comparison to go by. I will however agree
with Jim in similar difference I perceive in the cup vibe Silvia vs rotary
Bricoletta. And of course quieter;-)
Kona Konnaisseur miKe mcKoffee
URL to Rosto mods, FrankenFormer, some recipeshttp://mdmint.home.comcast.net/coffee/Rosto_mod.htmUltimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.

4) From: R.N.Kyle
Yes it is worth the trouble.

5) From: Michael Dhabolt
I would not go back to a vibratory pump after doing the conversion.
Mike (just plain)

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