Slight update here, but with the Giottos blower I'm getting a very clean grinder, but my dose in and out is now .5-.6 grams under on the out, which is very strange.

Did 3 shots and had 20 in and 19.4,. 19.5 and 19.4 out.

Nothing else changed, but using the blower at the end.

Strange stuff...

This was also my experience when trying to single dose an on demand grinder. Some coffee will have to build up and get stuck in places (mostly underneath the bottom burr) permanently before it stops randomly retaining some (I think, just saying that based on my experience).

Yes, I agree on the build up. Just shimmed up SSP HU burrs on my Ceado e37j and ground a shot to ballpark dial it in. Very first grind on a totally clean grinder was 1.5g off from what went in to what came out. No amount of brushing or pumping a home made blower got close to getting out what went in. Second grind: .2g off. Third grind: 0g retention.

And yes, 64mm SSP HU red burrs needed to be shimmed up to get them to touch on an e37j. A shim up of .9mm bottom and .9mm top got them up to a height were they now touch before the top carrier bottoms out with room to spare.

My modded SJ for single dose was fine but I didn't care for the work flow. I had to grind, bellows, brush, grind, and bellows again to get close to zero retention. Alignment was easy and it felt like it would out last me.

I jump around with different roasts and preferred single dosing before single dose grinders became popular so I guess I'm used to the extra work. It's another work around to play with in finding ways to be more efficient.

Thanks for all the tips and suggestions.

The anti popcorn device has been working really well. I take the cap off and pour the beans on a running grinder and all stay in.

After 20ish seconds, I do the air puffs and bellows and am done around 30 seconds total.

Just had a God shot on the grinder so I figured I'd share.

Coffee: Coffeebar Huellas. From Peru, washed process. Roasted on 5/22. When I picked it up, the bag was still warm

Dose: initial weight:15.3, after grinding 14.6 in the portafilter.

92 degrees Celsius, 32 seconds and 27g in the cup.

Damn it was good!
Tasted like POM (pomegranate juice) followed by dark chocolate aftertaste. Body was there but light and overall very "juicy".

I'm hoping I can replicate it and will report back.

Thanks for all the suggestions and tips and having a great forum. Really digging this right now.

About 8 shots in and the retention is zero or less than .2g now which is where I was before.

Consistency is still dead on as is the taste.

I have another SJ that I ll gwt back up to running with the Italmill burrs and see how they compare.

Slight update again.

Ground coffee for my in laws at a coarser setting and put the SJ back to my previous setting for espresso and still got the exact same shot for dose out and time.

Very happy with the set up and will try to post a comparison between Italmill burrs, cast v2 and Omega hand grinder.