I like to figure out ways of accomplishing things with my espresso machines. Many machines are not supplied with pressure gauges, and some of those gauges are tiny and difficult to read and small gauges tend to be inaccurate anyway.

It is difficult to find gauges that read in the pressure range required for espresso machines, in my experience, and many have really bizarre units. I saw one that measured pressures in terms of millimetres of alpha bromo naphthalene! What????? I discovered that one can obtain all sorts of pressure gauges from China. There are Chinese online stores that sell them, as well as ebay stores. (They do not seem to be auctions very often.) They usually cost about US$10.

I purchased one of these gauges, mine is calibrated from -0.1 to 0.15 MPa, the standard scientific unit of pressure, (1.0 bars=0.1 MPa) and then went to the local hardware and obtained a so called brass 1/4" pipe cap. No dimension on it is anywhere 1/4", the designation seems designed to confuse people!

I simply drilled a hole in the cap and cut M6x1.0 threads in it with a tap.



This works particularly well with machines with a detachable steam wand.

It, of course, can be used for any machine with a steam wand, though the diameter of the steam wand and the pitch may vary from machine to machine.

I made this thing because I normally monitor pressure with a special boiler cap with a gauge, but sometimes I discover I want to know the pressure after the machine is warmed up. But it would work fine for a primary pressure gauge test device.

I always enjoy Robert's posts and photos. He uses his home machine shop to great advantage again!

Here's my kit for adjusting P-Stats on a variety of lever machines. The pressure gauge works with steam or water. It has an accuracy of + or - 3%. It cost me $13 at a shop that sell and fixes pressure gauges. I could have paid for a gauge that had greater accuracy but the price jumps up about 300%. Since we just need to be within a certain zone of pressures to have tasty espresso, extra accuracy isn't needed.
I used the rubber hose with a worm clamp for the La Pavoni Europiccola's removable steam wand.
The other fittings let me pull a reading off machines with removable steam wands ir wands with removal tips.
I also have used the gauge to place the needle of a refurbished pressure gauge in the correct position during reassembally.
I keep a washer with my kit because some fittings don't seal tight.

This chart helps me when I adjust P-Stats with my gauge or with a machine's gauge.
Not all machines use PSI.
This chart ties into another discussion about spritzing water out of the water tap. As you can see, in the closed system of our espresso machines, the temperature of the water exceeds the boiling point of water at sea-level.
When water in a closed system at a higher temperature than it's normal boiling point is exposed to room temperature and pressure, it flashes into steam.

OE sells something similar in spirit that I have found to be very useful:

http://www.orphanespresso.com/Steam-Wan ... _2033.html

It could be improved by having an extra fitting in the mix that allowed rubber hoses of different diameters to be swapped in and out quickly to accommodate a larger number of steam wands (the Oscar steam wand come to mind...)

There are many different 1/4 threads
most likely its British gas threads . they seal in the threads /are conical

Us uses a different ,and and ,,
isnt there any more info ??any letters ?

A 1/4 pipe thread is for a pipe that has a 1/4 hole inside it
the outside is much bigger than 1/4.