Isomac gran macinino grinder won't grind fine enough

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#1: Post by RoasterRob »

Trying to fix one of these for some friends. It simply won't grind fine enough. Adjustment is one complete rotation of the hopper but the finest setting is still too coarse. Anyone had one of these apart? I started undoing all the screws but it doesn't seem very keen on coming apart. Don't want to scratch the highly polished stainless panels. Thanks in advance.

Rob vL


#2: Post by JonS »

Mine wouldn't grind fine enough when I got it, either.

There should be a limit allen bolt which is tapped into one of the adjustment holes on the adjustment ring. This catches against the screws in the top of the body, underneath the ring. You need to back off this allen bolt, and you'll be able to go finer.

To access it, take the lid off the hopper, and remove the small screws in the bottom of the hopper. The finger guard will come out, and the hopper should then just pull out of the adjustment ring. You ought to then be able to see clearly into all the adjustment holes around the adjustment ring...look for the one with a bolt in it, and unscrew that bolt somewhat. You should then be able to go finer.

Put everything back together in the reverse order to how it came apart, and you should be good to go.

You shouldn't need to go inside the grinder body.



#3: Post by JonS »

Oh, and now I've reminded myself, for future reference:

If you do want to take the case apart because there's something else wrong, then, you need to unscrew the adjustment collar completely (depending on that allen bolt I mentioned, you may need to remove the hopper as I described previously to do this, so you can stop it from catching)

Then, remove the screws on the top plate around the thread where the adjustment collar screws in. Make sure you note which one came out of which hole, on mine they were different.

Then, lay it on its back and remove the screw that sits middle front on the base. This should allow you to remove the entire front/top plate by pulling it forward, over the spout, which will then come free.

Do not remove the 4 huge screws on the sides of the grinder, these just hold some cross-bars in place between the 2 sides of the case.

I had mine apart to bypass the portafilter switch, the head of which kept falling off every time the PF touched it, and I found it less than useful. But you don't need the grinder apart to make it grind finer 8)


RoasterRob (original poster)

#4: Post by RoasterRob (original poster) »

Hi Jon shortly after posting i went back and had another look. After undoing every screw i finally spotted the allen screw bolt and worked it out. Course now there was a reason to pull it apart. To put the 2 spacer bars back in place and the earth wire. If only i had waited a day after posting. Thanks for the reply you have obviously been there.

Rob vL


#5: Post by JonS »

Heh, heh. I think those two spacer bars, and the related "undo me" screws on the sides, must be Italian humour 8) I'd forgotten about the earth wire, it's a while since I had it apart.

Glad you got it sorted in the end though !



#6: Post by Squidlyspresso »

Hy guys,

how would you rate the Isomac grinders. how does the grand macinino compares with, for instance, the Rancilio Rocky?

Thanks ,

Never lose your tamper!

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#7: Post by cafeIKE »

In Best $100 to $150 second grinder
another_jim wrote:The Isomac grinders are, as far as I could find out, fancy cased versions of a very low end Italian mochapot grinder.


#8: Post by Squidlyspresso »

Ahhh grreat, that's what I wanted to know. I'll go check out the thread.

Never lose your tamper!


#9: Post by guzaho »

Here's a set of pictures I took to illustrate the process on an ISOMAC Macinino grinder:


#10: Post by RasmusDJ »

Hi, do you still have the picture, i just got the Isomac Gran Macinino grinder, but it's not fine enough for my Silvia. The screw has been undone, but as of I bought it used, i'm having a hard time to locate where its fine. And at some point, it sounds like the blades are touching each other. The click before, it's still not fine enough.

Any ideas.