Changing Burrs 101 - Beginners' Thread

[BoldJava]

This is a beginners' burr changing thread.  Most here are very comfortable with tackling stuff, burr changing included.  This post is for the rest of us that are a bit intimidated with the mechanical aspect of our habit.  Here's hoping it helps one mechanically challenged person to tackle changing their burrs.  If I can do this, anyone can.

Why change them?  Six months ago, when I flipped a couple of Mazzer Minis, I sensed it was time for new burrs for the Macap MC4.  The MM was giving a fluffier grind.  Humm...almost 5 years on these Macap burrs.  Let's see -- about 2 lbs per week x 52 weeks x 5 years and we are over 500 lbs.  When I bought the grinder, I remembered hearing a ridiculous number for the life of a burr.  I have since read that 500-600 lbs is about tops.

So, off to Chris's Coffee for new shoes.  $35, done:  http://www.chriscoffee.com/products/home/mazzerparts/mazzersburrs

[BoldJava]

Next, break out the needed tools.

~  Rags, check
~  Stiff bamboo toothpicks, check
~  QTips, check
~  Awl, check (optional)
~  Phillips head screwdriver, check
~  Flat head screwdriver, (walked out of the picture - temper tantrum)
~  Paper towels, check
~  Screwdriver magnetizer, check (I have learned this the hard way)
~  Shopvac, consoling the screwdriver

[BoldJava]

OK, take off the hopper.  Simple retaining screw.

[BoldJava]

Take off the dialing index collar.  Three things to do first.

1.  Notice the setting -- write it down "5," looking at me.
2.  Stuff the throat with paper towels.  Saves chasing those tiny bugger screws.
3.  Use that stiff toothpick or awl to dig out the coffee dust from the heads of the retaining screws.   It is too easy to strip the heads if you leave that dust in there and try and back out the screws.

[BoldJava]

Now, before you start loosing the upper burr carriage, mark the spot that is dead-on aligned with the front of the grinder (near my thumb joint).  This helps you remember where you need to end your tightening after the burrs are replaced.

Remember, on a Macap, the burr carriage is threaded differently.  To loosen the carriage, turn counter-clockwise and count the number of turns until the carriage comes loose from the grinder.  Note and write down the number of turns and where that marking point comes loose (16.25 turns, loose at 9PM on the dial).

[BoldJava]

Take your time.  This thing isn't going anywhere.  Now might be time to console the screwdriver and vac.

Flip over the burr carriage and look at the thread.  Use a toothpick and clean up any coffee that is caught in the thread.  Don't get too anal about this but it is a good time to look at it and clean, where needed.  First I wiped it down with a rag, went after the most obvious with a toothpick, and re-wiped it. Done.

Some suggest using a food grade oil or a smidgen of olive oil on the threads.  I have never needed it and don't want the oil there.  Just a magnet for coffee dust.  Avoid it.

[BoldJava]

Next, go after that top burr.  Pick out again the coffee dust from the heads of the screws.  Get a good hold on the burr carrier and apply pressure down, threading out the screws.  Use this as a chance to clean the base of the burr carrier.  Mine was jammed with some dust under the burr, probably from a time I choked it with a Turkish grind.

Wipe it down again and install the new burr (on a Macap, top and bottom burrs are identical -- not sure on other makes).  Don't worry which is which. Put screws in, assuring that the burr is seated correctly.  Rotate the tightening (don't honk on one) of the screws until they are all tight.  Don't overdue it.  These will have to come out May 2016.  Voila, 1/2 way home.  New shoe.

[BoldJava]

Bottom burr.  Yuck.  Though I clean the grinder about every 4 months (with disassembly), I have some coffee residue in the lower chamber.  Go down stairs and grab the shop vac.

Vacuum out what you can.  Now, put the Qtips and toothpicks to good use, breaking up the impacted crud.  Keep that shop vac running, stuffing the tube right into the snout of the grinder.  

Now, magnetize that screw driver.  The second burr is sitting down in that chamber.  Trust me, you don't want to break those tiny screws loose and then have them tumble to heaven-knows-where.  Clean up the screw heads again, vacuum again.  The lower burr shaft will spin.  Stuff a rag in there which precludes the shaft from spinning.  Bust the screws loose.  Lift out the burr, again using the opportunity to clean it up.

Once satisfied, put the lower burr in.  Boom!  Two shoes done!

[BoldJava]

Time to reassemble. OK, remember to put your stepped-stopper into the collar before starting to reassemble the upper burr carriage.  (I have forgotten every single time I have cleaned Mr. Macap).  Find the starting point (9PM), where the carriage broke loose when you disassembled it.

Stop at the point you marked (16.25 turns).  Perfectly aligned, putting the index collar back on.  "5" perfectly aligned, looking at me.  Now, check your "0" point where your burrs begin to rub.  Before changing, mine started touching at 1.3.  Turn on the grinder and begin to turn it down and voila, right at 1.3, the burrs begin clacking at me.

Run about 1/4 pound of old beans through it.  They will grab some of the residual manufacturing oils off the burrs.  Check the grinds.  Fluff city has returned.  I did it.

You can too.

[peter]

Dave!  Has someone or something else taken residence in your body?  This is a new B|Java we have here folks, and it's almost scary!

Big-time congrats my friend!

[Tex]

Why not go ahead & pull the lower burr carrier too; then you can give that sucker a thorough cleaning. I soak burrs & all in a strong detergent solution, then use a s/s toothbrush (Home Depot/Lowe's welding dept) to scrub the grooves. I do a complete tear down every time I descale my espresso machine - approx. once every 3 months.

Test for burr sharpness: Drag a burr over your thumbnail - if it digs in it's still good.

[BoldJava]

Blown away by the differences in grind when I made espresso today.  Fresh burrs.

Dan Kehn had a post about tired burrs - - early blonding, ever tighter grind needed.  He is spot on.  As I made the espresso today, had to dial way up to not choke the Silvia.  Much tighter tail and later blonding.

B|Java

[Tex]

Blown away by the differences in grind when I made espresso today.  Fresh burrs.

Dan Kehn had a post about tired burrs - - early blonding, ever tighter grind needed.  He is spot on.  As I made the espresso today, had to dial way up to not choke the Silvia.  Much tighter tail and later blonding.

B|Java

I'll bet many times the user thinks the espresso machine is worn out, when it's just tired burrs. Glad that's all yours needed; maybe it'll encourage others to change theirs.

[BoldJava]

This was one of those "I needed to see it to believe it."

B|Java

[Tex]

This was one of those "I needed to see it to believe it."

B|Java

It's about the cheapest upgrade you can do.