Build Your Own PF Pressure Gauge

[RapidCoffee]

Sorry, no PF gauge to sell. But an inexpensive alternative is to build your own. Cost: about $10, one trip to the hardware store, and seconds to assemble:

PFgauge.jpg (66.69 KiB) Viewed 25787 times

Parts list:
1) pressure gauge with a 2" dial and 1/4" NPT diameter thread on a lower mount, rated to 200 psi (14 bar)
2) 3/8" to 1/4" female brass reducing coupler
3) Teflon tape

Some obvious points, but perhaps still worth mentioning: you have to remove the spouts from your PF. This may require clamping the spouts in a vise and pulling hard on the PF handle, but mine broke loose rather easily. The Teflon tape prevents the gauge from leaking under pressure (wrap it in the same direction as the threads). Use the PF gauge without a filter basket, or you will get leaking between the basket and the top of the PF.

I've tested this against the onboard gauge on my Vetrano, and the readings are remarkably close. Here it is in action on my S1:

NineBars.jpg (92.32 KiB) Viewed 25788 times

[chas]

You must have a real steaming machine if I am reading the steam boiler pressure gauge correctly. 1.5bars and well into the red?

[RapidCoffee]

Very observant! My steam pressure gauge is off by 0.5 bar. In fact, my first post here was a plea for recalibration suggestions.

The steam boiler pressure is probably about 1.2 bar. I've adjusted my brew pressure to about 9 bar.

[Endo]

Sorry, no PF gauge to sell. But an inexpensive alternative is to build your own. Cost: about $10, one trip to the hardware store, and seconds to assemble:

Excellent ! That's exactly what I was looking for (just needed the fitting and thread dimensions). Off to the store I go.

[Endo]

Back from the store. No gauges anywhere. Seems I'll need to shop around a bit more.

I'm thinking of doing a slight variation. I think I'll buy the 3/8" fitting for the PF with a quick connect (like the fittings in the machine) and run 8" of 1/4" silicone tubing up to another 1/4" quick connect fitting on the 200psi 2"gauge. It'll be like the PF gauge from CC but with a flexible line instead of the 1/4" copper tubing. This way I don't need to stand on my head to read it.

If it works out well I might even install a tee fitting in my machine and install the gauge up on my cup warmer fence so I'll have a dual manometer (like the VII)....except I'll actually be able to see it when brewing. (It'll look totally "steam-punk").

[RapidCoffee]

That sounds like a more elegant solution. Mine is quick 'n dirty (but it works).

If you want something even more sophisticated, check out Bob Roseman's solution. He added a needle valve to simulate the flow of espresso. There will be a pressure difference between the blind filter (no flow) and the typical flow rate of a normale double (~2ml/sec), especially on a vibe pump. On a rotary pump, it's probably only a 0.5 bar differential.

[Endo]

Wooahh. That's very nice. I missed that post in my search. Thanks.

[fiddlefly]

Eh Endo which stores did you go to ?
I was in Canadian tire on Sherbrooke street yesterday and they have manometers... they are in psi though... is that okay?
I do not know how to convert psi s to bar... guess ill have to do a research.
I got one but for my water line. I also got a flow pressure regulator thing. (actually I did not get these at Can Tire but @ a plumbing retail store.) I actually went to a couple hardware stores and they did not have any of the supplies mentionned here.
If you need the store's address or phone # just ask
(It's in the east close to Frontenac street)

[fiddlefly]

So I just got back from Da plumbin' shoppe and I got the whole thing set for...13.51 $ Can. Thats like .02 $us!
Anyhow, its not in Bar but in psi and kpa and 200 psi = 1400 kpa so i guess 1 bar= 100 kpa!
I am really happy that Rapid coffee posted that!
Thank You!

[RapidCoffee]

That's correct. BTW, Google is your friend for unit conversion. Just type "9 bar in psi" into the search box,
and voila: 9 bar = 130.5 psi

Always glad to help out a fellow home barista.

[Endo]

Eh Endo which stores did you go to ?

I tried Rona Hardware on the South Shore. They had a gauge for an air compressor that went to 200psi, but no water gauges.

I'll try tonight at Reno Depot and Home Depot. I think they carry more heating and plumbing supplies than Rona. After that I'll try Canadian Tire and finally a dedicated plumbing shop (if all else fails).

I don't think I'll get the whole "needle valve" setup. I'll just assume the brew pressure is 1 bar less then the static backflush pressure (I'm not sure what the exact drop is. I'll need to read "neede valve gauge" post again to see if there is a clue).

[RapidCoffee]

FWIW, mine is an inexpensive air-filled gauge. It seems to work just fine with a rotary pump, but you might see oscillations with a vibe pump. They don't stock fluid-filled gauges at my local hardware store.

[JohnB]

So I just got back from Da plumbin' shoppe and I got the whole thing set for...13.51 $ Can. Thats like .02 $us!

I wish! Just bought a couple vac pots from a tea shop in B.C. & the exchange rate was decent(20%) but not that good. At least it covered the shipping costs.

[Endo]

FWIW, mine is an inexpensive air-filled gauge. It seems to work just fine with a rotary pump, but you might see oscillations with a vibe pump. They don't stock fluid-filled gauges at my local hardware store.

I'm not familiar with the gauges used for espresso machines. I just assumed a standard 200 psi 2" gauge used for a air compressor tank would not work for measuring water pressure. I looked on the package and it didn't specify (air or water) so I assumed water would get in and ruin it. Are you saying I can use an air type gauge or do I need one specifically for water like this?

http://www.plumbingstore.com/pressuregauges.html

That would simplify my search if I could get the air compressor gauge from the local hardware store air tool department!

[RapidCoffee]

That's exactly what I'm saying. The air-filled gauge works fine for me. Just drain the water out after measuring the pressure.

[fiddlefly]

This is what I got (lower left #1743)
http://www.lyncar.com/plg/cat/pl/index. ... m&pageno=7

[Endo]

OK. Found the parts at Reno Depot. Cost was about $15 for the guage another $20 for the fittings and copper tubing (10 feet was the minimum length they had). Oh well. Still very cheap. Only about the price of shipping alone from CC for the LaSpaziale gauge.

I'm getting 140 psi (9.65 bar). Seems like a good number so no OPV adjustment is necessary.

One thing I forgot on the first try was to remove the double basket before taking a reading. Water goes around the basket and sprays everywhere.

Here's a photo:

Home made brew gauge

backflsuh.jpg (52.83 KiB) Viewed 25665 times

[RapidCoffee]

Sweet! Much nicer than my no-frills model.

[fiddlefly]

Yes!!!
Lookin good! Nice job!

[Endo]

The gauge is an "Orbit" model for a water sprinkler system.

http://www.amazon.com/Orbit-Sprinkler-S ... B00004S1TD

It comes with a 3/4 female fitting to go to a standard outdoor hose. You can remove it and there is a 1/4" male fitting underneath. It says on the Amazon site to use cold water only. Didn't notice that when I bought it. Oh well, still seems to work fine at 95C.

The fittings are standard "Master Plumber" stuff. I put a tee junction and a plug at the bottom thinking I could add a needle valve or maybe drill a small hole at the bottom to allow some flow during the measurement. But that might have been a bit too fancy.

[LJCoffeeGuy]

or for $64 for the dual manometer and $15 for the capillary tube adapter you can do this......

IMAG0177.jpg (136.02 KiB) Viewed 25619 times

I did this yesterday. I still have to clean up the edges of the cut out and put a bit of filler.

[chas]

The gauge is an "Orbit" model for a water sprinkler system.

http://www.amazon.com/Orbit-Sprinkler-S ... B00004S1TD

It comes with a 3/4 female fitting to go to a standard outdoor hose. You can remove it and there is a 1/4" male fitting underneath. It says on the Amazon site to use cold water only. Didn't notice that when I bought it. Oh well, still seems to work fine at 95C.

The fittings are standard "Master Plumber" stuff. I put a tee junction and a plug at the bottom thinking I could add a needle valve or maybe drill a small hole at the bottom to allow some flow during the measurement. But that might have been a bit too fancy.

I actually have a Rainbird version of the same basic thing that I bought a couple of years back. I use it to attach to the sink in my utility room so I can check the house pressure from time-to-time. Comes in handy from time to time since I have a well. The interesting thing about the one I have is that it is actually graduated in PSI and Bars - well in Kg/cm2 but apparently that's what BAR is. After looking up the Rainbird guage on various places on the web including Rainbird's own site, it looks like they have dropped the kg/cm2 scale and jsut show PSI on the current model.

[Endo]

or for $64 for the dual manometer and $15 for the capillary tube adapter you can do this......

I did this yesterday. I still have to clean up the edges of the cut out and put a bit of filler.

I think I'll buy the new front panel for $35 and make life easier. Can you show a photo of the the "capillary tube adapter" installation?

[chas]

If you look at the side-by-side photos of the VI and the VII on the page linked below, just above the optional timer photos is a pair that shows the area of the expansion valve and 3-way. On the left VI photo you can see there is a brass coupling that is capped off on the bottom. To attached the group pressure capillary tube you remove the cap and screw on the fitting that comes with the capillary tube which ends up as you see in the photo on the right.

I don't know if this fitting is in the exact same place on the mini or not but it should be the same process.

s1v2/S1vsVII.php

[Endo]

I don't know if this fitting is in the exact same place on the mini or not but it should be the same process.

It's a little more complicated on the Mini. There is a tube already on the bottom of the expansion valve that returns flow to the vibe pump. From what I understand, I need to add a brass tee fitting to tap brew pressure (as shown in this post):

viewtopic.php?f=35&t=971

[chas]

I checked the exploded diagram and see what you mean. It looks like on the Mini you need to add a new Tee in-line adjacent to an existing Tee in order to connect the capillary tube to the gauge.

BTW: This is no longer a Swap Meet thread. I think I'll soon move it to the Tips and Tricks area.

[Endo]

Didn't you see the picture I put in my "dual monometer mod" post. It shows the tee fitting used in the mk2 and the single elbow I have in the mk1. You just need to buy the tee, and then run some silicone line and a "quick connect" to the back of the dual gauge.

Chris tells me he's ordered all the parts and they'll be here in about 2 months. Should be about $100.

[chas]

I did see the post but I wasn't seeing the difference in the two. Now I get it. In comparing this picture to the exploded diagrams on page 37 of the parts manual, it looks elbow #7329 is the part that gets replaced by the Tee.

[sakurama]

For what it's worth McMaster Carr is an amazing supply house of pretty much everything. Their catalog is about 3-4000 pages but the site is very easy to navigate. In building a few motorcycles it's been an invaluable resource and now that I'm about to rebuild a V1 I'm sure it will come in handy. Anyway, here's a link to about 10 pages of pressure guages:

http://www.mcmaster.com/#water-pressure-gauges/=lh6wl

They even have guages marked in Bar if you want. Not always the cheapest but always the most selection. On the east coast you can order at 5pm and have it in the next mornings UPS. I think they have west coast warehouses as well.

Gregor