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Macap Grinder - Conversion to
a"stepless" adjustment mechanism
A true rival for Mazzer Luigi?

One of the buzz words from the past 12 months or so with regards equipment has been Macap.  The Macap range
first started to gain attention a few years back with their auto-tamper device and then as I said they became the
grinder to have summer 2004.   

I first bought one early 2004 (by pure coincidence - not because I was ahead of the pack) and have been using it
everyday now for about 8 months, including using it intensively at a trade event.  The models I have are the MXA.  
This has pretty much the same specifications as a Mazzer Super-Jolly with automatic switch.  Anyway I don't want to
do a review of the grinder but I just want to highlight one major annoyance with the grinder - and for this reason
alone I believe that Mazzer have nothing to worry about.










The main problem I see is that the grind adjustment is done in increments - i.e. the adjustments are done in stages.  
The Mazzers are stepless and in theory there are infinite grind settings.  After using the grinder for quite sometime I
personally think that the steps/increments are too big; finding a grind setting you are happy with is difficult.

For example, after I did the
"showdown" page yesterday I spent a good few hours trying to push my shots better and
better and gave the new modified
group a good workout with the bottomless PF.  I then realised that the Macap is
very limited and as we know by now the bottomless PF is a very good training tool.  I just couldn't get the pour at the
right speed - the setting I wanted was inbetween clicks on the grinder.  Arghhhhhhhhhh!  It was so annoying and
really I cannot believe that a serious company would manufacture an espresso grinder that is not stepless.
So what exactly is the problem?

The problem is the upper burr carrier.  On both grinders the lower burrs are fixed to the shaft of the motor - i.e. they
are the ones that spin whilst the upper burrs are fixed.  However that is not quite the case with the Macap
arrangement.  

           
Macap Burrs                                       Mazzer Burrs








The problem is that the upper burrs are fixed to the adjustment collar - the part that screws in and out of the top of
the grinder.  So when you turn the adjustment collar - the burrs move too.   On a Mazzer grinder the burrs are not
fixed to the adjustment collar and turning to collar ONLY moves the upper burr up and down.  On a Macap not only
do they move up and down but they turn.  

I have wondered why they have adopted this (inferior) arrangement and can only assume that it was some Patent
issue.

So in actual fact the upper burrs are not fixed at all and the collar can be turned quite freely - in fact the collar does
move when the grinder is on!  So what Macap have done is to lock the collar in place with a spring loaded pin that
mates with holes on the underside of the adjustment collar.  To adjust you push the pin down and then it will spring
back up if you let go and lock in place.
So what can we do?

I played around with a few ideas.  The solution is of course to remove the pin.  This then gives us one major (and
dangerous) problem - without the pin in place when you switch the grinder on the collar will move clockwise and will
unscrew itself!  We need to stop the collar from moving when the motor is on.

Solution 1-  Teflon tape on the threads.

My first idea was to put some teflon tape on the threads of the collar.  This would have the immediate effect of
making the collar rigid but then once you start adjusting the grind a few times the teflon will break apart and even
make it difficult the remove the collar again.  
Don't do this, it was very difficult to remove the collar.

Solution 2 - Put a brake on the collar

After abandoning the teflon tape idea (it took me about 15 mins to get the collar off) I then had an idea.  The
Mazzers have a sort of lock on their collars preventing too much adjustment, I decided to use this idea. I would then
drill and tap a hole in the collar so that a simple screw will lock the collar against the main body and stop if from
moving.   Very carefully I used my drill press and a few minutes later the hole was done, all I had to do was then tap
the threads.
This website is created by Paul Pratt, Hong Kong 2004. If you would like to use any of the images or text I am sure
I will say yes, but please ask first!  

Email me here.
REMEMBER THAT YOU CANNOT REMOVE THE LOCKING PIN FROM THE MACAP
WITHOUT FIXING THE COLLAR IN PLACE AS ABOVE.  IT REALLY IS A VERY
DANGEROUS THING.  WITHOUT THE PIN IN PLACE THE COLLAR AND THE HOPPER
WILL UNSCREW.  I HAVE WARNED YOU.
The serious part - liability disclaimer and
safety guildelines


A typical dirty grinder.
Mazzer upper burr carrier
The adjustment pin - removed.
Tapping the threads for the screw.
Another view. You can see the burrs at the bottom.
Done!
Almost done.
The final modification

My only concern with this screw arrangement was that the screw has to push quite hard against the main body to
stop the collar/burrs from moving.  This will of course make a right mess of the paint, so I then made a small rubber
sleeve to slip over the bolt.  This prevents the bolt from cutting into the paint.











Does it work?

It works very well.  The grind adjustment is now stepless like a Mazzer and I am happy now.  There is however 1 very
important safety issue.

WITHOUT ANY SORT OF LOCK IN PLACE THE GRINDER SHOULD NEVER BE USED OR SWITCHED ON.  
DOING SO WILL CAUSE THE COLLAR AND THE HOPER TO SPIN AND IT WILL UNSCREW!!!!

Because I have the rubber sleeve on the bolt it means I can tighten it up without any fear of the hopper moving.  It
looks a bit ugly so what I will do is find a butterfly type screw to make tightening and loosening easier.  

Now to me the grinder is not only a real beauty, but has a comparable grind quality to a Mazzer.

Paul 28/01/05
The modification in place.
To lock and unlock you mustadjust the screw.
Another view.
A Macap sandwich.
A very good looking grinder.
Hardly visible from a distance.