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500 Grinders

500 Grinders: What I learned about vintage European Hand Coffee Grinders

by taking them apart and putting them back together again.

By Doug Garrott

Autodidacticism (also autodidactism) is self-education or self-directed learning. An

autodidact is a mostly self-taught person, as opposed to learning in a school settingor from a full-time tutor or mentor.

Hand coffee grinders are small utilitarian objects manufactured for one

purpose.....grinding coffee beans. I have restored grinders over 100 years

old and grinders less than a year old and in some cases, like an old pocket

watch, took them apart just to see what makes them tick. Some grinders

were all hand made and as the evolution of the grinders progresses more and

more mass production methods were obviously used. Hand coffee grinders,

by their sheer numbers represented a large vibrant industry in the European

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manufacturing sector, logically so, for before the introduction of preground

coffee the coffee mill was the only way to process the bean to the brew.

Before getting in to specifics of grinder construction and design, a few

general observations:

a coffee mill will only grind beans for the type of brewing method available or

popular during a particular historic period.....if a culture predominantly used boilingmethods, as in the United States, then most coffee mills will grind an overall coarse

grind with little attention to the finer grinds. Examples are drip brewers in France

using a medium to coarse grind. Moka pots or Neopolitan coffee makers (theupside down drippers) which use a finer drip grind. Turkish coffee mills of course

producing a very fine grind. Each historic period of coffee grinders has a

brewing correlation in real life. As grinder technology evolved, the range of

grinding capability widened....manufacturers went from single grind designs(though nominally adjustable) to a more universal grinder, although most grinders

are best at one type of grinding over another, the marketable illusion of universality

seems important for all grinder makers. coffee mills were (and are) a competitive manufactured product which display all of

the self promotion and marketing that we see with any product. Some grinders

appear to be super fancy and likely were sold at a premium price, but themechanism and build is on par with less fancy models. Plain Jane grinders often

grind as well if not better than the fancy ones. The label or badge was an

important identifier and brand recognition was important. This is of course anotherexample of "the more things change the more they stay the same" and vintage

coffee grinders, though sometimes seen as quaint or coming from another age

("they don't make them like that anymore") their manufacture was subject to the

same pressures and considerations as any manufactured object. Ample evidence

appears of cost cutting measures, design changes to simplify production, theintroduction of side by side "economy" mills within one company, the copying or

borrowing design elements from another company, and the changes in grinderdesign to meet changing consumer tastes and preferences. All of these aspects of

manufacturing, and more are evident in coffee grinder design and manufacture over

the years. Many design innovations over time were indeed improvements whileothers actually cheapened the design to the detriment of the grind....like any other

product, some hand grinders were made to sell and others made to use, some were

made to last and others to last just long enough. And as we see with hand grinders

of modern manufacture, some will not even grind coffee to any reasonable level ofconsistency but are still sold, at fairly low prices, to the uninformed for gifting or

decorative purposes....so one can only assume that even grinders from "the goldenage" represent many of these same ideas that we can observe today. Just becausethey are old or hand made did not make them immune from shoddiness of

construction, unfortunate shortcuts of manufacture, or an imbalanced relationship

of form over function.

when attempting to trace grinder lineages, ages, or model groups by decade there

was a lot of transition of design through time. Some grinders with design elements

from the 1930's, for example were made in the 1950's and some design elements

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never were completely dropped by a grinder manufacturer and superseded by the

"new improved" design. It is often impossible to accurately date a grinder to a

specific decade, but only to a general period of manufacture, or even better ageneral style of grinder.

lastly, it is impossible to predict grinding ability of a coffee mill based on almost

any of the design factors to be discussed in this document......I would like verymuch to be able to state a positive correlation between "Zassenhaus post a ball

lower bearing" to espresso grinding, or " Dienes long handle exposed funnel "

designs to good french press grinding. Hand grinders are unpredictable and seemto refuse to cooperate in our desire for them to function in a predictable manner.

This is not a buying guide or consumer guide to hand grinders but an attempt to

record my general, and specific observations of hand grinders having seen so many

from the inside out and outside in.

The concentration of our grinder restorations have been with German hand

grinders: Robert Zassenhaus (Zass), Peter Dienes (PeDe), Kissing und

Mollman (KyM), C.A.Lehnartz, Armin Trosser (HT and AT as well asTrosser rebrands), Leinbrock's (Czech), Ahner of Austria, Italian mills such

a PB, DP, Fraber and Tre Spade, French grinders by Peugeot Freres, the

DeVe mills from Holland, and other obscure or simply less common brands.

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To begin by defining a few terms......

The coffee mill is composed generally of two parts, the box, and the grinding mechanism.The box is composed of the outer wood frame of the box, the top wood plate and thebottom wood plate. The grinding mechanism consists of a lower and upper bearing, inner

and outer grinding burr, a hopper/funnel system, and some adjustment mechanism for

loosening and tightening the grind setting. This adjustment is always made by forcing the

inner burr upwards into the outer burr either by pushing from below or pulling fromabove. The box components are assembled with nails and/or screws and the grinding

mechanism is installed with screws although sometimes the outer burr is fixed in place and

not removeable or adjustable. This drawing is of the more modern dropped hoppergrinder design.....the older design used an exposed funnel/hopper and independent top

bearing.

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These are two Zassenhaus grinders of about the same era.....the grinder on the left has anexposed top funnel and the one on the right has the bean funnel recessed into the top plate

of the box. This is an important design change for all hand grinders.....a great leapforward of sorts. The revolutionary change here is that on the old school grinder,

exposed funnel, the outer burr was affixed directly to the bottom of the thin wood top plateand the hopper was made of thin stamped brass, generally chrome plated, made in 3

parts: the funnel with screw holes to to wood plate and the top and door mechanism,

made in two parts which slide over each other, all thin brass made by a stamping process.These parts had to be hand fit and assembled. The top bearing is a heavy steel V shape

also attached to the wood plate, an upside down V.

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VS

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When thinking about this design change a few observations immediately spring to mind.

First, the old schoold design required an extremely long burr axle. This long axle affixed

to a turning handle creates a greater lateral force at the top bearing than does a shorter burraxle leading to greater potential for bearing wear. Also, the lower bearing which houses

the adjustment lever in this case is at the extreme top level of the box, making it a long

reach for finger adjustment made neccessarily through the drawer opening. This designshows a combination of difficult factors, first the thin brass hand assembled (and easily

damaged) exposed funnel and the long burr axle subject to increased lateral forces which

demand a much stronger top bearing for longevity. By applying the thick wood block

UNDER the top plate and forming the funnel IN the wood rather than of formed metal thedesign could be tweaked infinitely. The burr was now much lower in relation to the

drawer opening (and the drawer), and for the first time the upper bearing could be

incorporated into the hopper dome or into any structural top hopper element that the

designer could devise. The burr axles could be shortened thereby reducing lateral forceson the upper bearing and the entire mechanism could be for the first time reduced in size.

This structural change in top plate design of the box is likely the most critical developmentleading to the Golden Age of hand grinders.....at once improving the stability of the

grinding mechanism and allowing much greater flexibility of design of the entire box.

The inner burr block could be made of a cheap but tough non decorative wood and simplyglued to the decorative top wood plate....this design change was indeed the great leap

forward and all other design advances built on this simple rough wood block.

This design advancement had certain ramifications for both grinder design andmanufacture. In the old school design, the top bearing could be made heavy and strong,

as thick as need be to sustain the turning forces. The hopper/funnel is completely

independent of the upper burr and functioned only to contain the beans (the bottom collar isalso a spot for the accumulation of old beans and grounds, against the wood plate). The

new design allowed the use of a lighter and thinner top bearing since the turning forces

were lessened by use of a shorter burr axle. From an ergonomic point of view, the big topfunnel of the old school mills are very easy to hold at the small point of the funnel. The

boxes are larger in general to allow finger access to the burr adjustment and in many cases

can be described a "Lap Mills"....they are generally easy to turn and hold and in most cases

a quality mill of this era grinds a very even medium to coarse grind with little effort. Thelarge steel burr was long lasting and the burr itself was very understressed and usually had

a burr adjustment lower bearing that did not force the burr close together to grind against

itself and become overly dull. But from a manufacturing and design standpoint, loweringthe funnel into an added wood block made sense....shorter burr axle, more stability, the

ability to use a lighter duty top bearing and once again, consumer preference came into

play as the new look was just that, NEW! No longer did one think of Heidi and Grandpa,but of a whole new look and feel for the kitchen. MODERN! And for the manufacturer,

also cheaper to make, less materials, cheaper materials (the wood block could be lined or

unlined, varnished or not) and the top plate could be made of wood that was decorative and

light, the crude underblock doing all the work. This block also helps keep the top wood

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from splitting or warping, again adding stability to the entire design.

Of course, progress always comes with a cost, for with the new design ethic, we no longerwill see grinders such as this beauty from the Old School

The use of the dropped funnel allowed grinder design to really take off in many new and

interesting ways.....materials for the hopper top expanded greatly into bakelite

thermoplastics, chrome plated brass, painted steel, chrome steel straps with wood doors,and a wide array of hopper dome and door designs. The key element was that the top axle

bearing had to be incorporated into the top design in some manner. The most obvious was

the use of steel cross strap which held the upper bearing. This design could be painted orplated and often was accompanied by the use of wood "clamshell" doors, and either one or

both of these wood doors open by the use of a swivel screw at one end. Another common

early bearing was a steel pressed dome which contained the upper bearing press fit into theformed steel. This design was simplified by using a simple rounded dome with a press fit

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bearing....a very economical design and one of the most stable top dome/incorporated

bearing designs. Of course, chrome plated thin brass was continuous through all

production, again a consumer preference and these domes were rounded or flattened withpress fit bearings, with the door either a swivel around the central bearing or a spring

hinged door of almost any shape. Ova tops with spring door in the KyM models,

rectangular tops with small spring door in PeDe and Zass, as well as double doors in someZass models. From a functional standpoint, when the upper bearing is isolated either in a

strap or on a non revolving half of a dome there is more stability than on the revolving

central pivot dome doors. These are the designs that the revolving door rotates under thefixed half of the hopper top. Often this design has the press fit bearing attached to the

revolving part of the door and the press fit can loosen over time and the upper bearing

becomes wobbly. The goal here is stability and durability of the upper bearing and

anything that degrades the stability can lead to grind inconsistency and eventual grinderfailure.

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