HomeRoast Digest


Topic: Super Jolly Bearings (15 msgs / 442 lines)
1) From: Michael I
I just picked up a Mazzer Super Jolly that had been used as the decaf  
grinder in a shop which was open for six months.  Cosmetically, it's  
got chipped paint, but other than that it is fine.  The burrs were  
very clean, as was the rest of the machine.  It was relatively cheap  
(< $300), so I couldn't really pass it up.
As I've posted before, I'm on an ongoing quest to put together a nice  
espresso setup for one of my friends.  The SJ is massive overkill for  
his level (and probably mine), so I'm tempted to keep the beast and  
give him my Macap M4, but I haven't decided that yet.
Anyway, upon getting the SJ home and giving it a test run, it sounded  
way too loud, even when empty.  So, I suspect that the bearings are  
shot.
I ground about a pound through it -- some for vac, some for espresso.   
I really like the ring adjustment on it, as opposed to the worm drive  
on the Macap, as I can change between coarse and espresso grind very  
quickly.  The advantage of the Macap,  though, is very precise small  
adjustments for espresso.
Since this was used for 6 months in a shop (even though it was decaf  
and a failed shop), I'm going to change the burrs.  The grind I got  
out of it appeared to have few fines, and pulled good shots, but I  
doubt the burrs have been changed in its life.
I can determine where to get, and how to change, the burrs, but I was  
wondering if anyone had any suggestions about the bearings.  I'll  
search the 'Net, but if anyone has any first-hand experience, please  
share.
-AdkMike
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

2) From: Michael Dhabolt
AdkMike,
Unless the SJ was used (seriously used) prior to the 6 months at the
failed business I would question your appraisal of the bearings.
There is always a possibility the grinder was well used prior to
ending up in the shop.  In fact, I'd check the burrs prior to
replacing them.  Pull the upper burr carrier all the way out (good
time for a thorough  cleaning in there) and scrape your fingernail
backward across the sharp edge of striations in the burr, if you can
feel the scrape instead of just rubbing across the edge - the burrs
are probably OK.  I have yet to see a SJ with bad bearings - these are
not the quietest grinders around when new, definitely louder than your
Macap.  Can you hear it when it has no beans in it at all? Should be a
little motor noise and a soft whirrring sound.
Mike (just plain)
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

3) From: Michael I
Mike,
It is, of course, possible that the grinder has more miles on it than  
I know of.  I'll take a closer look at the burrs before I decide  
whether or not they have to go.  My main concern is the other problem.
It's very possible that it's not the bearings, but something else.  I  
expect it to be louder than my (tiny by comparison) Macap, but this is  
loud enough that it's difficult to talk over, even when empty.  The  
sound is definitely metal-on-metal, but I can't tell if it's part of  
the burrs touching, or a bearing sound.  The grind adjustment seems to  
be working properly, as I can get consistent espresso or press pot  
grind, so it's not as if the business end of the burrs are rubbing  
together.
If I spin the burrs with my hand (turning the burrs with the hopper  
off and no power), I can hear the noise, as well, though obviously  
much softer.  I don't feel any significant resistance when spinning,  
either.  It's a consistent sound throughout the travel of the burrs,  
so I don't think that it's something that's off center.
I don't have a lot of time to strip this thing down right now, but I'd  
like to make sure it's salvageable, or I'll go back to the seller.
Thanks,
-AdkMike
On Dec 22, 2008, at 12:16 PM, Michael Dhabolt wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

4) From: Rich Adams
The "business end" of the burrs do not ever touch, even if you tweaked the 
setting as fine as it can go until you hear them touching,,,it's the raised 
edge on both burrs that touch, never the cutting teeth.
A couple of machine screws and the doser comes right off and you will have a 
nice side view into the motor cavity to help determine what might be making 
the noise.  The motor brushes spin awfully close to the internal support 
structure of the Mazzer, like feeler gauge close, so it's possible it got 
dropped or something to knock the motor out of true alignment.
Rich

5) From: Michael Dhabolt
As Rich (good recommendations) identified - getting to the internals
is easy.  Before going to the internals, pull the Hopper and upper
burr carrier (turn the adjustment ring clockwise - toward coarser -
until the upper bur carrier comes completely out.  Then spin it -
possible that one of the burr screws is loose in there ??  I'm really
reaching here.  If the bearings were bad enough too generate that kind
of noise, I would expect that you'd be able to feel it when spinning
the motor.  Clean the upper burr carrier threads well before
re-assembly, set it in place, turn in the 'loosen' direction of the
threads (clockwise) until you feel it fall off the end of the entry
thread prior to tightening (counter-clockwise) - - you don't want to
cross thread this - not a common problem.
The inspection of the upper end should take about three minutes.
There may be something hung up that is obvious when looking down into
the lower burr area and jogging the motor.  If you still get the noise
with the upper burr carrier out and everything that is visible from
the top is tight and correctly in place (not much in there - lower
burr and screws) then Rich's course of action is next.
Mike (just plain)
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

6) From: Michael I
Since you and Rich have responded so quickly, I decided to stop doing  
the work I was supposed to be doing, and go and play with my grinder.
I removed both burrs (which are definitely not that sharp), and when  
spinning by hand, still get the same noise.  There was a bit of muck  
underneath the lower burr, but it wiped easily away.  I removed the  
doser, and while I can see into the side of the motor, there's nothing  
obvious in there causing it (nothing I can see moves when I spin it by  
hand).
My inexpert ears tell me that the noise originates about halfway down  
the shaft, around the "Mazzer" badge on the back, and not from the  
top.  It's very hard to tell, though, so it could be anywhere, really.
I did not take off the bottom, but from the side the motor looks like  
it's pretty solidly locked in there, so I'm not sure what I'd be able  
to do by removing the bottom.  I expect that getting at the bearings  
is not easy.
Any more suggestions are appreciated.  I can take some video and post  
it, since I know I'm not describing the sound very well, but that  
would take some time.
-AdkMike
On Dec 22, 2008, at 1:12 PM, Michael Dhabolt wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

7) From: Angelo
You could get a stethoscope at an auto store to help locate the sound...
A
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

8) From: Rich Adams
No more suggestions from me, but I did find this for an exploded view to at 
least see what's inside.http://www.rosito-bisani.com/oscommerce/JOLLY_COFFEE_GRINDER.pdfAlso, there is a SJ overhaul thread on toomuchcoffee.com.
And, this on HB:http://www.home-barista.com/espresso-grinders/mazzer-super-jolly-what-are-signs-of-motor-bearings-on-way-out-t2015.htmlGood Luck!
Rich

9) From: Michael I
Thanks, Rich.
A cursory search had led me to HB, as there are a couple of threads there
dealing with it.  I'll check out the other stuff -- the exploded view is
promising.  Judging by the drawing, I think it's quite likely the bearing
(12 on the parts diagram) and now I have a part number.
I'd just like to try to validate that it is, indeed, the bearings that are
the problem before I start what could turn into a bigger project.  Taking
the motor apart doesn't look like too much fun.
-AdkMike

10) From: Rich Adams

11) From: Michael Dhabolt
Michael,
Removing the stator of the motor is unnecessary.  The bottom of the
casting is easily removed, then a person should be able to identify
which end of the motor the noise is coming from.  If you are sure it
is a bearing, I would probably re-negotiate the price. replacing the
bearing should be within the ability level of the average to medium
tinkerer but I have never had to do it so can not give you a how-to
from first hand experience. I would probably call EPNW parts dept. to
find out if the bolt in the upper end of the motor shaft is right or
left handed. .
Unless you are pretty well set up with pullers, presses and the
various tools that just might be needed you might consider putting it
back together get your $ back and look for another.  I can't seem to
find a price right now for those bearings - - $50 to $100 wouldn't
surprise me for a set of high quality bearings of a somewhat unusual
lineage - if they are a common size you might get away with half that.
 I've bought a half dozen or so used Mazzer's thru the years and never
run into one with bad bearings.  As well constructed as the Mazzer
grinders are, I would expect it to be a fairly straight forward job.
If you decide to get that far into it yourself, don't hesitate
emailing me direct (off-list) I might be able to help out a bit.
Mike (just plain)
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

12) From: Rich
Its a generic bearing.  McMaster-Carr and probably 10.00 ea or so.  The 
bottom casting is either aluminum or zinc die casting and removing and 
replacing the bearing will require doing it right the first time.
Michael Dhabolt wrote:
<Snip>
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

13) From: Kris McN
Michael,
You've gotten a lot of good advice about the Super Jolly, I just wanted to
tell you that my Super Jolly is loud as heck.  I bought it used a little
less than a year ago.  It's really, really loud.  Sometimes the volume
decreases temporarily when I'm changing the setting, and especially as I'm
running rice through it during my biweekly cleaning.  It didn't occur to me
it was a problem - I replaced the burrs and gave it a good cleaning when I
got it and I didn't see anything wrong so I thought it was a feature and not
a bug.  I use it multiple times a day, never had a problem other than the
noise, and it gives great grind.  Maybe I should have been worrying all
along (?).  For what it's worth....
Best,
Kris McN
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

14) From: raymanowen
In the Mazzers, the motor bearings withstand all of the grinding forces. I
was hoping to install an angular contact ball bearing at the top of the
motor. After probably twenty years of use, I assumed the bearings might
stand replacement, and maybe Mazzer hadn't spent the extra for a good thrust
and radial load bearing.
Not to worry- the more I dug the vertical six pole PSC motor apart, the more
it looked like a Sherman tank. The grinder's design doesn't load the
bearings radially, and there is no radial play.
The axial thrust bearing wear would allow the motor shaft to shift downward,
increasing the space between the burrs and shifting the zero point. With the
new burrs, the zero point was (-12). Over two years, the zero point has
shifted 0.0012", is now (-14).
I don't know where the wear is occurring - the burrs themselves feel
incredibly sharp and the grind is fabulous. Bottom line, the latest blend
(.6 E. Harar Green Stripe, .3 MMGold, .1 L-A + ?few beans L.O.) is already
headed for the stratosphere. The Harar and MMGold are right out of the
roaster.
Left overs are always incorporated for the disclaimer- "Ask your cupper if
it's right for you."
Cheers, Mabuhay and Magandang Gabi -RayO, aka Opa!
-- 
"When the theme hits the bass, I dance the Jig!" - -Virgil Fox at the Mighty
Wichita (ex- NYC Paramount) WurliTzer- 1976
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20

15) From: raymanowen
"... The motor brushes spin awfully close to the internal support structure
of the Mazzer." If they existed, they'd be like an electric drill, Skil saw
or vacuum cleaner. Maestro grinders do have brushes and a gear train like
the electric drills, maybe not as robust.
Absolutely right on the burrs' non-interference design, but brushes are
stationary.
Sorry- there ain't NO Brushes or Starting Switch in the big Mazzer motors.
The knob on the side operates a way-oversize control switch that energizes a
latching motor contactor which can be de-energized by the fill switch if it
has a doser.
Permanent Split Capacitor motors don't have these failure points. They don't
fail unless you drop the damn things. Even so, the motor might even survive
the drop test- then it might need new bearings.
The Major was the only thing Brown was carrying up the walk two summers ago,
sweating rivulets. Mazzer ships the brand new ones double packed in enormous
boxes with hand holds. A big person might be able to carry it, but Mazzer
doesn't intend single-person handling, even in their box.
Stop looking for parts that don't exist. They will be ice skating in the
Place of Fabled Heat before you find a place to put any brushes you may
have. They're not on any Mazzer pictorial diagram or parts list.
Cheers, Mabuhay and Magandang Umaga -RayO, aka Opa!
Got Grinder? Still?
Homeroast mailing list
Homeroasthttp://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20">http://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.comHomeroast community pictures -upload yours!) :http://www.sweetmariascoffee.com/gallery/main.php?g2_itemIdx20


HomeRoast Digest