Rocky burr wear

[pinch]

when buying a used Rocky, is burr wear the only real concern? I understand the motor to be a mother, and unlikely to wear out... anything else to be concerned about? Also, how do you know when the burr set needs replacing? Many thanks.

[HB]

Rocky is built like a tank and the burrs are the only concern when buying used. FWIW, the Mazzer Mini's owner manual (link) says its burrs are good for 300 kilos (400 for the Super Jolly). I've not read a similar manufacturer's claim for the Rancilio Rocky, but it makes sense that smaller burrs work harder than larger ones to grind the same amount of coffee. The accounts I've read on CG suggested replacement every 2-3 years for "typical" home use. Fortunately burrs aren't a large cash outlay.

PS: Chris suggested offline that with commercial grinders, he always goes by weight of beans ground through a set. Otherwise, wear indicators would include coffee overheating and clumping, having to grind finer and finer, shot volume decreasing before blonding and grind time increasing.

[pinch]

thanks for info, Dan. While pricing out burr sets this morning, I found this advice at http://www.espressotec.com/umpartsRancilio.asp

Replace after 750 - 100 lbs, or after first errant screw in hopper.

Not mfgr, but sage advice nonetheless.

[HB]

Thanks for the pointer. However, I think the first number is a typo and they meant 75 - 100 lbs.

[miKe mcKoffee]

FWIW I replaced the burrs in my Rocky after a little under 2&1/2 years use. I noticed an improvement, both in grind quality and speed of grinding. If I was buying a used Rocky I'd order a burr set as soon as the purchase was a done deal.

[jasonmolinari]

Glad to see i'm not the only one replacing the Rocky burrs after about 75 lbs. I was confused because i had seen number saying they last 200 lbs...

I replaced them, and the defective flavors i was getting in my drip brews at work disappeared.

I don't know how you all did your burrs, but the bottom burr had to be pressed into the brass carrier on mine..good thing i had an arbor press here at work!

jason

[MichaelinA2]

Hi...

While remaining burr life is an important consideration when evaluating a used Rocky, may I also suggest that burr alignment be checked as well.

The top burr set should operate in the same plane as the lower set.

Burr alignment can be confirmed by unscrewing the top burr holder and painting the outer contact edge of the upper burr with a black magic marker. Reassemble the unit and adjust to the "zero" or burr touch point. Run the machine for a second or two with the burrs just barely touching. Unscrew the top burr holder again and check to see if the magic marker has been uniformly removed from the top burr edges.

If the burr set is NOT operating in the same plane, it will can be seen by a marker wear pattern that is not uniform (wear on one side, or the other).

Unless the burr pair is in precisely the same plane throughout the grind operation, the probability is great the result will be disappointing.

...my $0.02

[jasonmolinari]

Michaelin, good point, but if one were to find that the burrs are not parallel, what can be done? Shim the burr?

jason

[MichaelinA2]

Nope... Unless I was looking for a press or drip grinder, I'd pass on it!

[jasonmolinari]

Pass on it...what if one already owns it?

[MichaelinA2]

I was under the impression the 'poster' was in the process of evaluating a potential Rocky acquisition.

If you already own it and it's out of warranty, well.... there's no easy way for the owner to fix it. Accept the fact that it will not produce a Mazzer Mini quality espresso grind, but will probably produce acceptable drip or press-pot grinds. And given this limitation, just enjoy using it!

[jasonmolinari]

Well i was just wondering, my rocky appears to be fine.. i just wont check it...ignorance is bliss:)

[IMAWriter]

Glad to see i'm not the only one replacing the Rocky burrs after about 75 lbs. I was confused because i had seen number saying they last 200 lbs...



jason

Wow...I was under the impression I would get 150lbs from a set...FLASH!!!!!
Are these figures for Espresso grinding?...if my first 75 lbs were ground at say, the 26 mark for vac pot, could I expect a bit more life from the burrs?
Not that a set is that expensive, it's more the risk of not installing the new ones properly...that alignment thing has me spooked!

[HB]

It makes sense to me that a finer grind demands more from the burrs, so yes, I would expect coarser settings to wear them more slowly. No idea how much more slowly though...

[cajun_brew]

Not that a set is that expensive, it's more the risk of not installing the new ones properly...that alignment thing has me spooked!

Yes I too was spooked a little about changing my Rocky burrs. This is my first grinder and I've never done this before until this weekend.
My Rocky is about 2 years old and have run about 75 lbs through it most of it for espresso for my stock Silvia. I knew it was time to change cause my grind number had very slowly worked its way down to about 3 or 4 from true zero (burr touching).

I ordered replacement burrs from WLL and after getting up enough nerve I dove right in. I've cleaned Rocky every 3 or 4 months so coffee build up around the screws was not too bad and after unscrewing the upper burr I went for the lower burr first. The lower burr turns freely so I wasn't getting purchase on the flat head burr screws so I used a ratchet (12mm I think) on the large bolt in the middle or the burr set to hold still while I leaned hard on the screwdriver and freed up the burr screws. The lower burr was still stuck on the burr housing from coffee goo but came off easy using a hard plastic thingie I had lying around to poke it with. With the new burr in place it was easy to turn it to align the burr holes up with the housing holes and screwed it down. The upper burr is even easier cause it's out on the counter and you can get around it better.

My threads aren't very loose but I used Teflon tape (only 1/4 turn for mine) to tighten it up a bit and I notice the hopper doesn't wobble up and down like it use to when I grind---- It's solid as a rock.

My grind went from 3 or 4 from Zero to about 11! (That's more like it)

I'm no "do it yourself" kinda guy ... I once had to tow my car to the shop after trying to adjust the rear brakes, but this was a very easy and straight forward for me.

My next upgrade was going to be a Mini or Macap grinder and then on to HX land but now I'm not so sure. I think Rocky will do just fine with a new HX machine until I can upgrade to a better grinder.

[DenverDude]

Hey all,

Last night I bought a used Rocky for my Silvia to replace an aging MDF. The owner swears that it is two years old, and that he only used it sporadically for a year before sending it to his basement for a year. Now he uses a pod system only. Its a doser, which I wouldn't have preferred, but the price was right ($125) so I snatched it.

I am not sure that he was totally truthful about the age since it has the 'Rocky' sticker under the 'Rancilio' sticker, which I know they don't have now. Does that make it a much older model? Anyway, it appears to be in fine shape, cleaned up well, and now I am wondering if I should just change out the burrs immediately, perform any other maintenance, or just let it ride.

Any thoughts appreciated.....

Mark

[HB]

...I am wondering if I should just change out the burrs immediately, perform any other maintenance, or just let it ride.

Why not remove the hopper, unscrew the carrier and check the burrs yourself? If they feel sharp, check them again in three months. Below is a closeup of what flat burrs look like when brand new:


Courtesy of Al Ruscelli's Mazzer Mini Burrs

[DenverDude]

Thanks for the suggestion Dan - I will do that this weekend when I have some time to take everything apart. Any other maintenance that should be done? Do these things ever need lubrication? Thanks again - Mark

[HB]

Not really. The Rocky is known for thread slop, so many look to teflon tape to stiffen the carrier movement instead of lubricants.