Based on the very helpful advice shared on these forums, I put together a Bunnzilla for pour over and drip brew. I found this site to have the most useful and detailed information and thoughtful explanations about the topic of high-performance grinders for these styles of coffee making, so thanks very much to the contributors on these forums.

Grinds with the original burrs seemed pretty consistent and fines were not excessive. But I had already bought the Ditting burrs, and when I opened up the Bunn, the burrs looked shot. The burr replacement seemed very straightforward. I bought the MillCityRoasters kit. I used the service manual and instructions from others here to replace burrs and calibrate them. I found it pretty easy; in fact, easier than calibrating my Vario with steel burrs.

I'm getting a fair amount of fines, though. I prefer using a gold filter over paper in the various brew methods I use. I enjoy the flavor of the oils and most of the antioxidant content in coffee is in the oils. Using these filters, I see fine sediment in the brews, and it affects the flavor marginally to significantly. Paper filter brews seem to ameliorate the issue for the most part.

Bottom line: Brews are good to very good, but both the Vario with steel burrs and the Lido 2 are producing better brews than the Bunnzilla. (I have not done side-by-side comparisons, but I have done same-days brews with the same beans on comparably dialed-in grind settings and same brew methods).

To fix the issue, I've started to put rice through the grinder. I have put two 25-pound bags through in the last couple of weeks. I think that I can see modest improvement, but not a lot.

My questions are:

(1) could burr misalignment be the issue? If so, how would I diagnose that?

(2) do I just need to run more beans/rice through the grinder and have some patience?

(2a) If beans and rice are the solution, is the recommended protocol what I have discerned from these forums and other sites: 100+ pounds of rice and beans, perhaps up to 300 lbs before the burrs are fully broken in. For rice, pour in slowly and use a course grind setting. Run some coffee through after the rice to get the rice fines out before using.

No idea about the rice but Ditting told me in 2010 that it would take around 300 lbs of roasted beans before the burrs hit their peak. I ran 15 lbs through mine & just started using it.

Could be both alignment and that the burrs aren't properly broken in yet. You could probably apply some of the lessons taken from folks aligning their Mythos grinders to the Bunnzilla and get a better alignment.

As for burr break-in, I've generally advocated doing the breaking in by grinding AT the grind setting you're intending to use it at most. I've recently heard contrary to this, Scott Rao suggests putting any grinder at it's finest setting for the burr seasoning process.

Thanks to both of you.

I'm going to troubleshoot alignment just to be sure I didn't do something stupid.

I'm now up to 100lbs rice and around 10lbs coffee. Today I did a side-by-side with the Lido 2. I eyeballed the grind setting, and since I only had a single Brazen available to me, had to sequentially brew the two grinds.

To me, the 2 were indistinguishable. Four work colleagues on a blind test all favored the Bunnzilla, although both were thought to be excellent. Interestingly, all four thought that the two had different taste notes, acidity, balance and the like.

I am not planning to run any more rice through Bunnzilla for now. I think the extra rice has moved the needle on the necessary break in. If it keeps improving with more volume through it, then all the better.

I have a bulk grinder, while not a bunzilla, it has ditting 89mm burrs. They look like very large kenia/Guatemala lab burrs. Anyhow, I've also noticed a lot of fines as I single dose and RDT. I think it's possibly just the fact that these are large flat burrs spinning at almost 2000rpm. I would imagine comparing to a Lido would exagerate the appearance. That all said, it's accepted that even the EK produces significant fines. It's also fairly documented that fines are not a detrimental taste of brewed coffee. However, they certainly would affect non paper filter methods from a sludge standpoint..

Hopefully I am totally wrong and it's just a matter of getting hundreds of lbs in.....

Any tips for checking the burr alignment on a bunzilla?

the Bunn service manual was helpful. cannot put my finger on a URL right now but it's not hard to find. Honestly, there's not much to mess up.

Maybe someone with an bunnzilla could use the Rafino to see what the spread looks like?

Considering buying an old bunn off a friend and one day make it a bunnzilla, but just use the burr s as are for now, so would be fun to do a comparison after aligning.

Someone actually did this... something along the lines of is something wrong with my bunzilla...post.

I Ro-taped my Bunn before alignment and after. I will try to find the pics.
Align burrs by drawing on sharp edges with dry erase marker. Turn grinder on and tighten until you start to hear a squeak.
Check burrs for where marker wore off. Shim opposite side with a piece of tin foil.
Repeat until you see even wear.