Are there flat manual grinders?

Grinders are one of the keys to exceptional espresso. Discuss them here.
RedPanda

#1: Post by RedPanda »

A question for folks here.... for the most part 99% of the manual grinders I have seen are conical (of all sizes both table and hand) and ghost burr (seen one hand one table top)... but I have never seen a flat hand grinder..... do they even exist?

baldheadracing
Team HB

#2: Post by baldheadracing »

Yes, but not really, as recently discussed in another thread: Zerno grinder post #55
-"Good quality brings happiness as you use it" - Nobuho Miya, Kamasada

cactus_farmer

#3: Post by cactus_farmer » replying to baldheadracing »

I don't understand, the grinder in that thread is an electric flat burr grinder, not a manual flat burr grinder?

Or were you just linking evidence of the fact that this topic has been discussed by someone at some point before?

baldheadracing
Team HB

#4: Post by baldheadracing » replying to cactus_farmer »

The latter. The particular post linked to discussed manual flat burr grinders last week.
-"Good quality brings happiness as you use it" - Nobuho Miya, Kamasada

RedPanda (original poster)

#5: Post by RedPanda (original poster) »

I think he was referring to the discussion that flat grinders needs the rpm to jettson the grounds as it grinds.

But the design of having a vertical mount solves that problem... so *shrugs*

Pressino

#6: Post by Pressino »

I think there were some very early (i.e. "antique") table grinders operated with a crank that employed flat burrs. I'll look around to see if I can find a reference.

ira
Team HB

#7: Post by ira »

The Apex is a flat burr hand grinder

Pressino

#8: Post by Pressino »

I found this old thread from HB.com:

Titan Manual Grinder

The old Spong grinders are conical, but strike me as somewhere midway between conical and flat burr grinders. I'll look around for old grinders with flat burrs, but they may have been intended for grinding other stuff, like grain, but could have been used for coffee.

Pressino

#9: Post by Pressino »

ira wrote:The Apex is a flat burr hand grinder
Yes, it uses so-called "ghost" burrs, which I think were the type used in the antique grain/coffee grinders I referred to above.

The manual Titan grinder discussed in the old HB thread I cited uses "real" modern style flat burrs...which, unlike the Apex, are suitable for espresso and Turkish.

ira
Team HB

#10: Post by ira »

My Spong, while mostly flat, certainly feeds like a conical. If you think about conical burrs, they will in general happily feed beans at speeds approaching zero RPM while most flats won't. So far, all flat burrs seem to have been designed to be force fed, either by beans being thrown into the burrs by spinning fast, fed with an auger or both. In contrast, most conical burrs start with what might be considered a built in pre-breaker, making it easier to get the bean into the actual burrs. A flat burr designed to be more aggressive at grabbing beans or with the addition of a pre-breaker might work fine as burrs for a hand grinder, but the diameter might have to increase significantly. But you'd have to put up with a grinder with a much larger OD, no flat burr travel grinders.

In theory, any burr should be able to be made in any shape. Flat burrs can in theory be made on much less expensive equipment than a conical and are a lot easier to design, though modern design tools may make translating a design between the two much easier.

And as a positive sign for the future of small conical burrs, I'd guess from the number of seemingly different styles appearing recently, that someone is making them on a CNC mill and trying to improve on what we have today.