Robo-Pavoni; learning to make espresso machine from scratch - Page 3

August 17th, 2008, 11:42 am

I'd like to see a detailed walk-through for drilling that pressure gage into the GH. If you're taking requests

August 18th, 2008, 9:17 pm

A quick reply: use two drills, one superfine from the bottom of the head, and the second 0.125 from the side. Hope they meet and drill carefully while paying attention to desired depth. The superfine hole should be outside the piston shroud, but inside the screen and o-ring. Once you see daylight, epoxy a 0.125 stainless tube into the hole and add a gauge.

August 19th, 2008, 3:45 pm

Very much appreciated.

Do you have any problems with coffee grounds getting stuck in that small hole? Looks like it would be the best spot for it, but I do still get grounds up in that channel after some shots.

August 21st, 2008, 10:59 pm

Grounds may get in there, but I've never had a problem with that. 10 bar keeps the tube clear. The volume in the gauge fittings is filled with water, so very little displacement is needed in the tube.

r

#25: Post by **SandBaggerOne** » May 4th, 2010, 10:55 am

What year was the group you used to make your Robo-pavoni? If your measurements in the Cad drawing are in inches they seem a bit different relative to the 1982 group I have.

Cheers,
Colin

September 5th, 2011, 10:23 am

Not 100% sure what year--I got rid of the body some time ago. But I've drilled two of them so far, both pre-millenium, and not seen any important differences.

-raj