rocksteady wrote:I looked at the hopper neck of my SJE, and it is a bit taller than the one on your SJ.

Yes. If there wasnt this problem of many iterations of mazzer grinders, it woulde be easier to offer plans or modification kits.

rocksteady wrote: I would like to try it out and maybe remix the design a bit. Do you have a 3D file that you're willing to share?

The engineer on fiverr wasnt a CAD/CAM workshop but here is an image of the file (cant attach the file) I supplied him with. Both parts were machined within tollerances but I did have to sand/file a slight bit to get parts to fit so my measurements were probably out a bit.



You will absolutely need to measure YOUR SJ to work out what you need. I would suggest beta testing with some simpler way of making the Mod. I used my grinder like this (below) for about a year, with a pvc pipe for the bean input tube and some folded plastic for the ground output. It's sitting by itself on an angle of about 51 degrees here.


You may find drawings online for your mazzer but I found it difficult to find anything accurate

rocksteady wrote:Your plan looks good. Does the grinder stay put with only the wood insert in the bottom? At the same time, you could shim the front bottom of the grinder with wood to compensate for the overcut if it bothers you enough. It probably matters little in the function, but it's an option.

The wood is attached from underneath to the grinder body in a beta way untill I decide on a few things like where/how to permanently mount toggle switches. When I sliced the body off I made a wooden guide jig around the grinder to make cutting it off accurate, I just didnt measure the angle of the grounds out chute as it wasnt attached when I made the cut. It would be possible to fix the extra foward tilt degree but it's a lot of effort and it's barely noticable. The grinder now is sitting about 44 degrees, not bad as i was aiming at 45 so its my grounds out chute thats out. My workshop is a couple of planks on saw horses and i dont have machine shop tools.

However...the extra 7 degrees angle has made a difference to the grind. Usually when I dissasemble the top burr assembly to clean, my grind setting is retained very close to perfect when replaced, within 1 mm on the ring. Now its on a more foward angle I have to set the grind to finer now.

Thanks for these drawings! I will work with it a bit and report back if I come up with something good.

The tilt is interesting. I tried it on my SJE and the balance surprised me. I think it might be cool to make a weighted angled base on which to attach the SJE with bolts from the bottom. One issue for me is that the SJE has a doserless cone with the controls on the cone lid and the angle results in grinds pooling in the cone that is now on a flatter angle. I could solve that by putting a half tube slide in the cone. Maybe next weekend

Apologies, my head got turned by Maak's SJ project.

I own an SJ Electronic with original doserless cone and only single dose with it. I never have a hopper on and keep the throat covered with a blank basket. This is what I think about it, owner bias included:) :
1. Solid build quality, heft and durability, feels like the commercial equipment that it is
2. Has two presets, manufacturer intended for one for single and one double shot. These are set by time and are pretty convenient. I set one preset to finish grinding 12 grams and the other preset for 14-15g depending on basket used. There is a manual grind button on top that I use to finish the grinding after I sweep down the stray beans and fragments. Here's a web image for reference, where the panel is in setup mode and showing the grinding time set - 17.95 seconds.

3. Fairly easy to single dose and brush out for low retention

This is my grinding flow:
1. Weigh and split the shots
2. Drop shot of beans into the hopper neck and insert appropriately sized jar in the neck to weigh down the beans and stop popcorning - I use a spice jar with marbles inside
3. Fit a plastic cup or dosing cup on top of the portafilter fork and under the cone exit and it stays put
4. Push the button that corresponds with the weight of beans inserted
5. Lift up weighted jar, brush down fragments and finish grinding
6. Lift control lid, brush out the grind chute - my finger guard is removed to allow access to the chute

If you want a fairly low risk entry to see if you like the 64mm flat burr grind quality, I would suggest the SJ or SJE first. Either will give you the Mazzer standard of grinding and you should be able to get close to what you paid for it, plus or minus, if you decide to move to another grinder. Personally, I don't feel a need for another flat burr grinder.

So you have this big cone-orifice bucket, from the stock, no fancy mods, right?
I have seen that some of the mods effectively try to do something similar.

And with respect to brushing, do you only brush on entry? No retention after the burrs and in the bucket?

There is one attractive used option for the one like this here, I am thinking...

I think on an an experience level and regarding retention, the stock SJ and SJE are a long way from perfect, but modifications on somethging this robust are easy enough.

On grind quality however, compared against other 64mm burrs, you can achieve a competitive result. Obviously it cant be compared to any large flat burr like weber workshops or commercial Mahlkonigs but with the ssp or other high end burrs you're going get excellent espresso grinding..

@rocksteady If it's taking 17 secs to grind 14g...are you burrs sharp? My original burrs were a little bit blunt and took about 20 secs for a 19-20g dose. Now with the ssp 19-2-g grinds in 10-12 secs.

old_bear wrote:So you have this big cone-orifice bucket, from the stock, no fancy mods, right?
I have seen that some of the mods effectively try to do something similar.

My first experiments were using a similar shape. I found it's not really the best shape but mazzer probably didnt want to change the main body shape that holds the doser. Having something this large though does allow easy cleaning of grinds from the top of the chute.

old_bear wrote:And with respect to brushing, do you only brush on entry? No retention after the burrs and in the bucket?.

I'm finding I dont need brush the bean input at all except when I dissasemble the whole burr chamber every couple of weeks and clean out.
With my ground output mod I can still access the chute in the body that comes direct from the burrs without any dissassembly. I brush this with each use and recover about 0.1g of grounds

Ah. So you still have to brush the funnel? Does the grind stay on its surface, or get stuck in the entry/exit?

On output mostly just a very fine mist of the finest grounds can attract to the aluminium tube. I dont see any way to avoid this but its a tiny amount.

Normally the exit from the burrs (the tightest point of exit) is clean, but ocassionally beans have been oilier and a small bit has built up there, maybe 4mm-5mm in the corner, but never blocked or anything. The stock SJ was blocked here often. I use one of those fan makeup brushes and just spin it inside the tube from the top.

Overall retention shot for shot is very low, sometimes even nill and on average 0.1g

old_bear wrote:So you have this big cone-orifice bucket, from the stock, no fancy mods, right?
I have seen that some of the mods effectively try to do something similar.

And with respect to brushing, do you only brush on entry? No retention after the burrs and in the bucket?

There is one attractive used option for the one like this here, I am thinking...

Correct, big stainless cone with electronic controls on the cone lid, no other mods other than removing the finger guard and anti static screen to allow brushing out the chute.

For brushing: Quick brush down the hopper neck for stray beans and fragments, a few seconds of manual grind button, then open lid to brush out chute and clean up the cone. Cover the hopper neck with a blank filter basket and it's ready for the next time.

Maak wrote: @rocksteady If it's taking 17 secs to grind 14g...are you burrs sharp? My original burrs were a little bit blunt and took about 20 secs for a 19-20g dose. Now with the ssp 19-2-g grinds in 10-12 secs.

That was actually a web image I found online as I mentioned because I replied while I was far away from my grinder.

I just checked, I have set the single button to 10.90 seconds for 12 grams and the double button to 12.50 seconds for 14-15 grams. These times use to be longer before I started using the weighted jar on top of the beans to push them down during grinding. According to the shot count, I've put over 50 Kgs since I bought it with 1-2 Kgs run through it, but it's actually more than that since my "singles" increased to 12 grams somewhere along the way. I believe the burrs are rated for 400 or so kilos so they should be sharp enough. I'm still interested in SSP, though.