it has done this since brand new. i resort to keeping hopper filled to add weight to the beans, setting the burrs so close that they hit each other when hopper is empty, tamping considerably harder than 30 lbs. rocky is now about 2 years old. i've already done the plumbing tape fix, though that might have been 18 months ago. any help will be greatly appreciated. thanks in advance.

This topic comes up every few months.
Some Rocky can't grind fine enough for espresso.
It's a science project to figure out why.

If this has been the behaviour from the get go, even when burrs were new, then I am not sure if you can address the issue. Make sure to rule out stale coffee (more than a few weeks old), channeling or using too little coffee before doing a move.
I used to have a Rocky and tried very hard to make it work for my new (then) Mini Vivaldi but the only real fix for me was moving to a Vario W.

My old Rocky worked fine on some beans, but could not grind finely enough for others. The only solution was to change the beans or change the grinder.

My Rocky was able to grind fine enough when new, but not with great adjustability. I took a few years away from espresso and recently have returned to it 3 years later. Now I could barely get there with the Rocky and one notch adjustment went from passable to gusher.

My burrs were very dull, completely worn out. While replacing them I also spent a good amount of time carefully centering the lower burr on the carrier. There is a fair amount of play and it took about 6 iterations of slowly nudging it around and then checking the centering by spinning the carrier by hand. I also now realize that the original burr set was not well centered as some others have reported before.

So for me new burrs and proper installation have made a world of difference. I am now working at +7 to +9 (from true zero) for most beans with one click being about 4-5 secs pour time. Much better than when new and totally acceptable for my uses.

Of course I am due to receive a Mazzer Mini tomorrow which I grabbed on sale from 1st line earlier this week. I am doing this primarily because I am tired of changing the Rocky from espresso to drip daily as fits our lifestyle. The Rocky will now be dedicated to drip.

Like "richardsaddiction" I'm returning to brewing espresso after a two year "layoff". My wife purchased a Silvia/Rocky combo for me back in late 2008. I have used the Rocky almost daily since that time, but mainly for french press and pourover.
From day one my Rocky would only do acceptable shots from +1 to +3 from true zero and that was only with very fresh beans. I could never choke the machine at +1 no matter how fresh the beans were. I even sent the whole unit back to Seattle Coffee Gear early on but they assured me the grinding was perfectly acceptable. I continued to make espresso until late 2009 and then I pretty much went to using the Rocky only for french press. Fast forward to a couple of days ago. I began home roasting about a month ago and have been inspired to brew espresso again. I ordered some new burrs since I estimated I had ground about 80-90 lbs of coffee in the Rocky. I decided to do the teflon tape mod as well since I had everything apart. With those 2 changes my Rocky is an entirely different grinder. First shot at +1 and the Silvia choked...same thing at +2 and +3. I haven't had enough time to thoroughly test but it looks like I'm now at the +7 to +10 mark for acceptable shots. Definitely a huge improvement from when the unit was new

While it has been discussed more extensively by others before, the mere act of removing and installing the same burrs in a different position on the carrier can show improvements if the parts (burr, carrier) were not machined precisely. From my experience the burrs are not of particularly uniform thickness (measured w/ caliper w/ some difficulty, varies from set to set) and the carrier could also be non-uniform. Therefore, with 3 screws for each burr you have 6 possible attachment points that could be tested (although I found I could not remove the lower burr w/o possibly damaging it so its easier to do this with the upper only).

On my Rocky, I tried this a few times w/ different burr sets and if I rotated the upper burr attachment to carrier, of the 3 possible options, there was usually one where the "zero" point of burr touch (once assembled) was the lowest and that was the one that I would use. Going from memory, I think the variability for different burr/carrier attachment configurations was at least a few clicks on the adjuster if not more (approx 2--4 clicks). Having a high point on the carrier mated with a high point on the burr could certainly explain why near "zero" grind would not be as fine as expected in some cases.

Overall, I could get good shots from the Rocky but consistency varied a bit (not so bad to be a deal breaker for me and I used for 9 yrs). I recently upgraded to B. Vario and the difference was discernible and worth the cost to me...mostly improved ease of use, consistency, and a notable but modest step up in flavor (more subtle nuances tasted). Overall, the Rocky must have produced more fines because if I broke apart dry pucks they would produce a fine suspension of dust (that I don't see with similarly disturbed dried vario pucks).

Pat

Pat, I'm pretty much set on going the same direction as you after some research, which is Rocky-->Vario. Good to hear you are happy with the upgrade. I go back and forth between press, pourover, and espresso and from what I can gather the Vario is the best option for a single "all-in-one" grinder. If I can find a good deal on a Macap or Mazzer I might just keep the Rocky for press and pourover duty, but I have limited space in my wetbar/coffee station so that option is not likely

Edit - scratch the not likely to add a Mazzer idea I alluded to above. Picked up a used Major for $140 a couple hours ago off craigslist. To good a deal to pass up so it looks like I will have two grinders now