Yes, quietness and bling/bragging rights. I do not believe it makes better espresso.Diggidy wrote:Sorry - but are there any good instructions on doing this? Is the rotary pump inside the machine? The main benefit being quietness I assume?
I could tell you how I did mine but it's actually so easy I'm almost embarrassed.
First some conditions:
1) The pump is driven by a motor, so the pump and motor are one assembly. Together they will be too big to fit inside the machine even though the BDB has a ton of extra room. This may be a mental barrier for the "home barista" mindset, but many of the large commercial machines have their pumps mounted outboard from the machine. It's why they too are so quiet. This also keeps things nice and reversible as you don't have to remove the stock pump.
2) I plumbed it from a softening filter I keep under the kitchen sink, directly to the pump, which is also under the kitchen sink. Plumbing is by FAR the easiest way to do rotary.
3) My pump/motor has it's own on/off switch separate from the machine. This adds simplicity too. But more importantly it gives me to ability to energize the 3-way solenoid at the machine with the regular machine buttons without having to run the pump at the same time. So I can let water into the puck at line pressure only without having to add pump pressure to it. Combined with my needle valve for flow control (Slayer mod), it's the ultimate in flow control.
4) I do keep a little water in the reservoir for steaming. Since the BDB has it's own separate pump and sensors for filling the steam tank, why mess with a good thing? I keep just enough water in it that I can barely see it in the sight glass. This is one of the huge things that makes this so easy.