I would like to convert my RR45 manual grinder to stepless. What parts to I need to purchase? I understand that parts for these grinders are getting scarce.

Maybe I am asking the wrong question. What I want to do is to convert the grinder so that I have a wider range of fineness of the grind. The ring has 48 positions and I understand there is something available that gives a much wider range.

Cafeparts has some; not sure if their in stock. But instead of spending a lot of money I would try taking off the grind adjustment notch selector first. Maybe it's stiff enough to hold the settings? Or make a wedge and slip it under the adjustment ring?

The collar on the RR45 will wander without something holding it. It doesn't have a spring counter pressure like the mazzers.
You need to work out some way to hold the collar in place that gives it infinite adjustment. I'd imagine its possible but requires some ingenuity.

I made my Fiorenzato grinder stepless using Macap parts. It took some tweaking but in the end it works well.

I attached the Macap notched-edge plate that was closest to the diameter of the outside of the upper burr carrier. this meant drilling and tapping the holes in the upper burr carrier where the mounting holes were in that plate. Then I mounted the Macap worm-gear so that it engages the notched plate. This took making some spacers, grinding some metal, and adding a spring; that was the hardest part of the job.

I really like the result.

I bought the 80-position collar a few years ago. As I recall, it didn't fit my Rossi exactly, but I was able to make it work, and it is still in use in a small cafe.

Anyone try just some teflon tape on the burr carrier?

Teflon worked perfectly on my Rossi grinder. Just make sure you use enough so that it takes up all the slack. The first time the hopper spun slightly when grinding. I took it off and added a bit more, mostly towards the top where the espresso range would be. Never had a problem, but just upgraded to a Super Jolly and wow!

I tried Teflon tape.
It works, but only if you never adjust your grinder -- then what is the point?
I found that if I adjusted the grind, the Teflon tape got chewed up and lost its holding power.

I didnt have any problem with that as I had quite a few layers of tape. This may depend on the grinder and how much play is available in the threads. More play, more tape, lasts longer, is my thought. I was never adjusting for anything other than espresso and didnt have any issues. But I would agree tape is only a temporary fix in converting to stepless.

I guess you could nip off top of the piece that holds the adjustment ring in place, put a rubber gasket on the bottom of the ring, and friction between the now nubless spring loaded detention pin and the gasket to hold it in place.

fishll: any details on differences between the modded rr45 and the SJ? I wouldn't have thought there'd be too much difference between two stepless 64mm flat burr grinders.