Olympia Cremina Boiler-Neck-Mounted Pressure Gauge Reducing Coupling

A haven dedicated to manual espresso machine aficionados.
User avatar
timo888

#1: Post by timo888 »

At this juncture, I'm not expecting anyone to commit to anything, but I would like to know how many Cremina owners are seriously interested in having the ability to mount a pressure gauge onto the neck of the boiler. In that way, you'd be able to watch the pressure while using the steam wand, and can see the drop in pressure when you let off some steam--one of the recommended ways of bringing Cremina's very hot water down to brew temperature.

This coupling would be for analytical purposes and making suitable adjustments and is not recommended as a permanent replacement for the factory cap.

I have found a company willing to make, in small quantities, an appropriate reducing coupling. The owner's daughter answers the phone, and she and her pop have been friendly and helpful. The company specializes in metric fittings.

I've asked them essentially for a 66mm tall 30mm diameter hex-shank in brass (same diameter as the lock nut) with one end a female 25mm metric parallel thread with 1.50mm pitch to fit over the Cremina boiler neck's thread and on the other end a female 1/4" NPT thread for the pressure gauge. Pressure gauges with 1/4" NPT male thread are readily sourced.

So let me know if you're interested by replying to this thread, and I can then pass on the quantity desired and get an exact quote instead of ballpark numbers. The ballpark range is wide: roughly ~$40 apiece if ordered in a quantity of six (6) and maybe as low as $4 apiece if ordered in quantity one-hundred (100). So, the greater the interest, the lower the price per unit will be. In any event it will be less expensive than ordering a dummy boiler cap from the factory and tapping an NPT thread through that.

Regards
Timo

Gregory Q

#2: Post by Gregory Q »

Hey Timmo...

Good thinking on the boiler cap. I was thinking of doing something similar, but cylindrical with a 1/8 NPT
female in the centre. A small pressure gauge with a back mounted male thread could then be used, and then whole thing could be surrounded by a wood (or other material) knob.

The net effect would be a slightly taller boiler cap with a slightly recessed, inset gauge. The other material
that I have been considering is Corian, a product made for kitchen counter tops. (It machines like wood, and is durable around heat and moisture)

Please count me among the interested.

Cheers
Greg
LMWDP #64

User avatar
espressoperson

#3: Post by espressoperson »

Timo,

Thoughtful of you to be sharing your industriousness with other Cremina owners. I don't understand most of what you described which is why I am so interested in buying your solution. How about offering a complete package, all parts including the gauge, if you are willing to put them together, charging for parts and labor, of course. Have you considered a permanent replacement cap and gauge? You might find enough people interested, even if it might cost more.
michaelb, lmwdp 24

msmacchiato

#4: Post by msmacchiato »

I like the complete package suggestion, since I live in a remote area and I am fairly clueless myself.
None of my machines have a gauge; therefore, it would be a new learning experience I have often considered. so, count me in!
LMWDP #153 "Every man dies, not everyman really lives"

User avatar
espressme

#5: Post by espressme »

Hi Folks,

Since this thread came up again, I am prepared to do a few gauges. Actually I am doing another one now. I am strongly suggesting that they be made up as usable only to set and / or reset the pressurestat. Yes, they could be made with a wooden knob below, and a back mounted gauge. The price goes up and the wood may break or split due to the heat. Still, probably a bit cheaper than an imported Oly gauge.
If there is interest, email me.
Sincerely
Richard
richard penney LMWDP #090,

User avatar
chopinhauer

#6: Post by chopinhauer »

Yes, definitely count me in please. I've long wanted to have a direct way to gauge the pressure in my cremina; just from time to time so I can make adjustments. The one in espressme's post looks pretty good for these purposes.
LMWDP #027

houdina

#7: Post by houdina »

I would be in for one.

Gregg

User avatar
espressme

#8: Post by espressme »

Since there is an interest, I would think this is a time to concern ourselves with the way the gauge is mounted.
The LaPav gauge shown is only available in bottom mounting. There is also an E-91 pressure gauge with a back mount. The cost of those gauges is about $40-$50. McMaster-Carr HERE has gauges that are available with the mounting connection on the bottom or the back. That means the gauges are vertical or, horizontal like the Olympia gauge. Search "Pressure gauges" on their site. 2% accuracy is about .05 Bar. The gauge should be 30PSI with the center 14.7 psi being equal to one bar. I would recommend a 2½" diameter.

Since there is no way to know which way the boiler neck is threaded, each gauge will, of necessity, be put in and adjusted by the buyer.

The horizontal gauge may be better in that it may be read however the cap is oriented. Either gauge may be directionally oriented by tightening with trial and error amounts of Teflon tape in the connection. There should be about one rotation available with the ¼ NPT taper threads of the gauges.

Best financial choice would be I make the adapters with a ¼"NPT threaded mounting hole and you individually buy the gauge that you wish. I can furnish an adapter from that to the LaPav gauge threads for $5 extra.
Thanks all!
Richard
EDIT: I could also add to all, a square ¾" shank to ¼" to ½" from the top for later use as a base for a knob of wood or something else.
richard penney LMWDP #090,

BillR

#9: Post by BillR »

I'm interested too. Richard, please keep me informed of the mounting options.

Bill
BillR
LMWDP #201

User avatar
orphanespresso

#10: Post by orphanespresso »

Richard....good to see you are keeping those hands busy, not to mention the grey matter. As an aside, the Elektra a leva gauge has the same thread as the LaPav gauge, and may be a bit cheaper by a hair. Nice mod for the Cremina though...sure beats constant fiddling with the pstat to get the temp right.
Doug