Oh, I believe you. It would be great if they made those exact pins of yours in brass. There are lots of threads on worn lever slots. I've seen it myself on a Riviera Baby and the Pavoni in this thread. The rear slot especially breaks down on vintage Creminas.

Added: Worn pins and lever slots often occur when they're insufficiently lubed. Recent posts here suggest the thickest bearing grease for that small, high pressure point of contact. Rich's (aka oldnuc) suggestion that a roller bearing is better than a roller in the rear slot makes sense. And there I doubt that a brass pin is very much superior to a steel one. To my eye acorn nuts don't look as good as those machined pins, which offer a nice change from chasing stray circlips around your workbench or having them fall off while in use.

Making a part such as shown in post #46 above from brass would be very easy. One could make the parts from hexagonal brass stock to make them easy to tighten with standard tools.

I found some "spike" nuts for chopper motorcycles that I put on mine after becoming bored with acorn nuts on threaded rods. (They are somewhat weird with Whitworth heads and M6x1.0 threads. Why they were manufactured in such a strange way must have an interesting story.)

The Microcasa a Leva has a particularly serious similar problem with the analogous roller seizing and wearing down the area on top of the group where it rolls. Owners of these machines should keep close watch to be sure that this roller is ROLLING and not SLIDING. Replacing this roller with a bearing would certainly be a good idea, particularly for machines that are used a lot.

The screw fit is quite loose until it bottoms out and tightens up nicely but still easy to take apart. I'd be happy to test any brass styles like in post 46. I have to get a metal lathe someday.

I used a hand drill and a file to go from 1/4 inch to a snug 6mm fit. The loose fit is likely to wear faster.

Let me clarify, the screw going into the end is a loose threaded fit, I think so one can open it without tools. The outside diameter of the pin fits snug.

Understood. Thanks! Someone wrote earlier about 6 mm being a bit too small for the pin holes, creating a loose fit, so I thought that had been the issue.

Turns out there is a tinkermill nearby, I might consider trying to figure out how to make these out of brass.

That said would one do 2 bearings with a longer spacer in between instead of three bearings? I wasn't getting the whole spacer and three bearings. Would 1 work? or did I read they would not turn?

From earlier in the thread:

OldNuc wrote:It should be relatively easy to make new pins from 1/4" bronze rod stock using common hand tools. Using a standard 8mm die it threads by hand easily as it is softer than soft steel. All you have to do is match the pitch of the nuts you use so you can tighten them onto the pins. Thread length should be controlled so mostly unthreaded rod is all that is in the clevis yoke. The 1/4" rod can be carefully cut down using sandpaper and a drill if you are careful and take your time. The 8mm pins measure .230 .232 depending on the wear in the clevis and piston rod. Sanding off 2/100" is not difficult. This does take some careful sanding and fitting so everything stays tight.

The rear roller is another issue as finding a single bearing is not easily doable so a stack of 3 bearings and spacers is required. The assembly is a real hassle because of the spacers required and the trick of holding everything lined up. I located bearings and making spacers is easy. When done the bearings are clamped tightly in the clevis and roll nicely with no resistance. I used common metric instrument ball bearings. These 2 modifications make a huge difference in how these machines operate and are well worth the time required to make and install it.

Rich continues with that instruction here:

Upgrading La Pavoni Worn Lever Pins and Insertions

Please let us know what you find out about getting some made!

forbeskm wrote:Turns out there is a tinkermill nearby, I might consider trying to figure out how to make these out of brass.

That said would one do 2 bearings with a longer spacer in between instead of three bearings? I wasn't getting the whole spacer and three bearings. Would 1 work? or did I read they would not turn?

The only bearings that are readily available have equal width inner and outer races so if you would like them to actually roll instead of slide you MUST provide clearance for the outer race. This requires a shim that only contacts the inner race. You can use 2 bearings and a center spacer if you want to machine one or if you make the shims you can use 3 bearings and the shims to get the desired total width. Depending on how much precision machining you feel like doing there are lots of possible solutions but when the dust settles the roller needs to be on ball bearings and have a width that will allow closely clamping the floppy clevis arms close to but not contacting the group.

What I posted originally was just a proof of concept idea that was actually functioning as intended. It is entirely possible to improve on this but it is both small in physical size and the tolerances are rather tight. Depending on the actual condition of the machine at hand will determine many of the final dimensions.

These mods have been in daily use since slightly before the original post with no failures or noticeable wear. The front piston rod pin is removed for the periodic group disassemble and clean and lube PM. I maintain the group so that the handle falls completely and smoothly by gravity alone after being lifted to the full up position with the group & boiler at ambient temperature. When this does not happen it is PM time. The group inside is polished.

Would aluminum be ok for the pins? Might match better than brass.