I'm putting together a sample/brew grinder by putting Ditting machined burrs into a Bunn G1 HD. The burrs have a 15000 lb duty cycle.

Asking myself, "How much coffee will it take to break them in?" raised a (familiar) specter of ignorance as well as a few threshold questions.

• What does it mean to "break in" burrs? Specifically,
• How is breaking in, different from seasoning? And,
• What happens to the burrs themselves -- particularly burrs with a near infinite life expectancy -- after 15lbs or even 50lbs, which doesn't happen after 2 or 3lbs?

Other, related insight is also welcome.

BDL

The Ditting machined burrs that I received had a fair amount of "flashing" on the machined edges. Right out of the box they produced a grind that wasn't much better then the Bunn burrs I'd replaced (lots of fines). I rounded up close to 15lbs of stale/cheap beans & ran them through the Bunn at a medium grind setting. This cleaned up the machined surface of the burrs & the drip range grind I typically use for syphon brewing was much improved. Ditting claims that the machined burrs won't reach perfection until you've run around 300lbs through them so they will be improving for quite some time.

You could probably reduce the break in period by grinding very light roast coffee, although I wouldn't get too carried away in that direction as green beans are somewhat like rocks.

This brings up the familiar notion of using minute or parboiled rice. On the one hand, such rice is believed to be faster than just using coffee to break in the burrs. On the other, there is some debate as to whether said rice is any harder than coffee to begin with, which leaves one wondering how it could then be any better than just using coffee. There is probably a satisfactory answer to this but I haven't encountered it yet. You may be just as well off with some lightly roasted coffee.

As to seasoning vs breaking the burrs in, if by seasoning you mean reducing the flashing/jaggedness of the machined burrs, I would think of these as the same thing. Perhaps others would have a more nuanced view of this.

..

happycat wrote:If flashing is the main issue, would it be totally crazy to just lay them face down on a 600-2000 grit sand paper and go around in circles in say 1-second intervals with checking in between? Automotive sand paper can be amazingly fine for feathering paint jobs.

Yes, please do this, then report back. Make sure you have several hundred dollars on standby for the replacement set of burrs.

The point to the minute rice is it's cheaper and faster than coffee. It's pretty hard to overdo it since it's quite soft relative to the burr's steel. But it creates sufficient friction to wear away the flashing and still leave a perfectly sharp burr edge.

TomC wrote:Yes, please do this, then report back. :roll: Make sure you have several hundred dollars on standby for the replacement set of burrs...

Reminds me of the car forums joke; sucking sand in the intake manifold to "port and polish" while the engine is running.

60% of the time, it works every time!

TomC wrote:Yes, please do this, then report back. Make sure you have several hundred dollars on standby for the replacement set of burrs.

The point to the minute rice is it's cheaper and faster than coffee. It's pretty hard to overdo it since it's quite soft relative to the burr's steel. But it creates sufficient friction to wear away the flashing and still leave a perfectly sharp burr edge.

Thanks for the sarcasm.

I was responding to an earlier claim that "Ditting claims it will take 300-400lbs before the burrs are at their peak" and the Uber Grinder people blasted similar burrs with glass pearls. But if the rice is empirically safer, great.

Yes, and you're correct (300 lbs before they're considered broken in), except it's not a claim, it's straight from Ditting USA, Nancy seems to always take these inquiries and it came straight from her.