sashaman wrote:Why is [the brew pressure gauge] showing 9-10 bar if the pump isn't running?
That's normal. As explained in Brew Pressure at Rest
, it's a closed hydraulic system, so the brew pressure gauge reading when idle will vary between zero and the expansion valve setting. The actual brew pressure can only be measured when the pump is running.
another_jim wrote:Isn't that exactly the same range of motion as a ball joint; only you have to take a longer path?
That's correct. I realized that I should have shown it more clearly in the video once it was already uploaded.
To clarify, if the wand is positioned parallel to the front of the espresso machine (i.e., pointing directly to the right), it cannot be tilted up/down directly. You must tilt it slightly back and then rotate downward, i.e., take a longer path to reach the same orientation that a swivel joint could do directly. I'm sure there's a technical name for this type of joint (two gimbals allowing rotation in two axes?).