Cabinet Hinge Specifications for butt hinges.
It is easy to guess the nature of man's first hinges. Leather, vegetable or fabric straps or bands are as effective now as they have ever been. If fact in recent times an updated version of this simple hinge has returned to common use, the plastic hinges found on video boxes and countless other cheap mass-produced items is simply the latest re-iteration of the oldest and simplest hinge.
This simple hinge has served basic hinging needs for millennia and highly durable plastics have given it a new lease on life. As a concept it does suffer two drawbacks. Firstly its ultimate strength is significantly limited and secondly it has no fixed center or pivot point. In order to make the action of these hinges more precise it is necessary to bring the attachment points as close to the desired pivot point as possible, taken to an extreme all the stress is focused on the smallest possible area which will obviously result in premature failure. In typical applications the strength issue is less problematic than the predictability of its swing. Precision joinery is rendered pointless if a door or lid closes differently every time. Still, in appropriate applications (such as the book) this hinge deserves our respect for its age and longevity.
Early Metal Hinges
The need for a stronger and more precise hinge combined with man's discovery of metals led quickly to the earliest metal linkage. Again simple effective ideas die-hard and the snipe hinge which consists of nothing more than two pieces of wire bent double and linked together still can be found doing duty as hinges in the less developed parts of the world today. Though these metal hinges are stronger and more accurate in their motion than their more primitive ancestors they still fall short of modern demands in both areas.
While the modern barrel hinge in which two interlocking leaves wrap around the same pivot pin was probably conceived by armorers and silversmiths it would have taken until the middle ages before this development would have had much impact in every day domestic life. For our purposes the barrel hinge appears early enough to all but monopolize this function from the 15th century onwards.
Even with their bewildering range of sizes and shapes barrel hinges have far more in common than otherwise. Those practical differences that do exist are largely confined to load bearing capacity and mounting variations plus a few special hinges developed for particular applications. It is in the areas of aesthetics and historical relevance that so much head scratching seems to take place. I hope we can address these concerns along with guidance on selection and usage of some special purpose hinges.
Hinges could of course be made of almost any metal but in the real world iron and brass have proven to be the best choices. The earliest hinges that have relevance to us were invariable forged from wrought iron. Wrought iron has many attributes that make it a particularly suitable. With primitive equipment and a good deal of skill this malleable material can be formed, cut and hammer welded into anything the heart desires with surprising speed. Once finished a wrought iron product will last and last, while its strength is common knowledge its resistance to corrosion is not. Wrought iron by virtue of its fibrous nature in which slags (molten mineral impurities) are included in the structure of the metal is far less prone to corrosion than modern steels.
Iron hinges were almost always surface mounted on the face of the door and casework. The simplest forms were the "H" hinge, shaped in the form of the letter H in order to provide for adequate mounting while avoiding the need to fold a long hinge joint and the "Butterfly" hinge where the leaves flare out from the joint for the same reason.
"T" shaped strap hinges in all shapes and sizes were common and added a degree of structural reinforcement to a door that might otherwise sag over time, more of an issue in architectural applications than furniture. Screws were not commonly available until the 18th century so hinges were fastened with nails, the more the better. These nails were clinched over to discourage their loosening.
The nature of wrought iron and the methods used to shape it do not encourage fine levels of precision or detail and because of this brass became the preferred material for use on finer furniture during the 17th century and beyond. Brass is an alloy of copper and zinc and has some particular attributes that suit it to hinge making and the other hardware needs of furniture.
Brass is easily cast, cut, filed and polished. It is neither the hardest nor the softest metal and in an application such as a hinge it is wear resistant. The hinges found on furniture up until the 20th century where cast brass and while somewhat prone to breakage seem generally to have held up well to the ravages of time. This century we find cast hinges have given way to those of pressed brass and extruded brass. The only virtue of pressed brass is cheapness. Extruded brass is another matter. An extruded brass hinge is machined from solid brass stock that has been forced through a die of the desired hinge section. This extruded brass is a hard alloy of great wear resistance. On no grounds aside from originality does an extruded brass hinge suffer in comparison its cast brass forebear. It is a stronger, more precise and longer wearing hinge that if finished correctly can only be distinguished from cast originals by its higher level of precision. With a few decorative exceptions all quality hinges these days are of extruded brass.
Hinges With a Difference
Aside from the modern European cabinet hinges generically known as 32mm hinges and Soss invisible hinges (neither of which we sell) we sell three types of hinge that differ from the conventional butt hinge.
The double acting screen hinge is a clever pair of interlocking butt hinges. Operating on the same principal as the Jacob's ladder these hinges can open both backwards and forwards (see photo).
The counter/card table hinge or the link joint hinge (see below). These hinges have a link connecting the two primary leaves. This additional link allows the hinge to fold back on itself without the usual upward projection of the hinge barrel, allowing for an uninterrupted working or playing surface. These hinges come in versions suited to surface mounting on the heavy folding countertops one might find in a British pub to discreet edge mounted versions used on elegant 18th card tables.
Knife hinges are popular with contemporary furniture makers because they downplay the role of hardware. When installed properly all that is seen is a small semi-circle of brass at the top and bottom of the door. With their substantial bearing surface and horizontal orientation they are capable of bearing reasonable weight, but bear in mind all the weight of the door is supported on one bearing in contrast to regular butt hinges in which the weight of the door is spread over four bearing surfaces.
Inset vs. Overlay
The doors in traditional furniture and cabinetry are almost always inset or flush, meaning the door is in the same plane as the surrounding cabinetry. This was and still is the most common application for a hinge and conveniently also the simplest from the traditional cabinetmaker's perspective. The introduction of mass-produced joinery and pressed hinges saw the adopting of the half overlay door by kitchen manufacturers and subsequently furniture makers. The half overlay concept eliminates the need for any kind of accuracy in joinery and thus has immense appeal. A door could now be off by a 1/4" and the overlay lip would cover the error. This overlay evolved into the 3/8" x 3/8" rabbet so a standardized hinge specification could be developed. Hinging a half overlay door was an unsatisfactory business until the pressed hinge with its thin leaf material allowed convoluted bends around the rabbet onto the door back and face-frame edge. Needless to say, these developments suited the industry much better than the customer and any self- respecting furniture maker should steer well clear of this style of construction.
Exceptions: The waist door of a tall case clocks was often of half overlay construction. To hinge this door with the hinge technology of the time required a little deception, the hinged edge of the door was left without a rabbet. Special hinges with one wide and one narrow leaf were available (see photo), these hinges allowed the door to project forward of the casework enough to accommodate the rabbet on the three other edges.
The French have used their "Fiche" hinges for centuries. These hinges are an excellent choice for half overlay construction but somewhat tricky to fit. Information and instructions for this type of hinge can be found elsewhere on our site.
270° Degree Opening
The demand for a hinge that will allow a door to open to 270° is constant and the substantial market for entertainment centers has only fueled this need.
We stock a high grade cranked hinge that allows for this degree of opening and our 270° instruction page describes these and another possible solutions.
Bright or Not?
Throughout most of the 18th and 19th centuries the typical butt hinge was meant to do its job without drawing attention to itself, functional items such as hinges and locks were not in competition with the designed elements for the viewers attention. Hinges were almost always mortised into the edge of the door and inside edge of the casework leaving only the front half of the barrel exposed to view. These days, perhaps because we are starved of contact with quality materials and objects we tend to fetishize those that we do come upon and polish up and display them inappropriately. This is not historically correct, rather they would have been finished along with the woodwork so as to blend in as much as possible. Typically plain butt hinges of an appropriate size were chosen.
Picking the right hinge for a particular application is very much a personal choice. So long as one stays within reason the choice you make will invariably function quite adequately. This is another of the multitude of small decisions the furniture maker must make that ultimately makes his work look unmistakably his and not someone else's. As a set of general rules one could say a typical cabinet door of between 24" and 36" will have two hinges, the 24" door might have 2" hinges, the 36" door perhaps 2 1/2" hinges. If the door is much taller than 36" it is worth considering a third hinge, more to keep the door straight than for any strength concerns. Taller doors on a wardrobe could warrant 3" hinges. That takes care of the length and number but what about the width issue. So long as the screw holes are fairly well centered in the wood thickness then the leaf width is not really a strength concern but it is a woodworking concern. Some people think it is easier to mount a hinge if the mortise is cut through the full thickness of the wood. There are problems with this thinking. Wood thickness' vary, perhaps the door is 13/16" and the frame around it is 7/8" or 3/4", one hinge leaf will either overhang the door or stop short of the mortise in the face frame etc. this is not elegant woodworking and it is not even convenient. Much better to establish the hinge width significantly less than the wood thickness and thus leave a stopped mortise against which the hinge can register for consistent placing. For 3/4" wood thickness a hinge that is 1 1/2" wide when open seems to have become a modern standard. When the weaker cast hinges were in general use a narrower hinge leaf that brought the screws closer to the hinge barrel and reduced the unsupported width of material was preferred. If a sense of historical accuracy is important then perhaps choose a 2" x 1 1/4" or 2 1/2" x 1 3/8" hinge. The last dimensional choice to be decided upon is the barrel diameter. This need not vary much in order to have a significant effect on the visual weight of the hinge. The three common diameters available today are 7/32", 1/4" and 5/16". The choice depends more on visual effect than strength considerations. Slender hinge barrels complement the elegant lines of period furniture. The heft of 19th and 20th century cabinetwork can suit hinges of greater visual strength.
This century we have seen the advent of loose pin hinges on furniture and cabinetwork. Originally conceived for house doors these removable hinge pins allow a door to be taken on and off its casework quickly and without tools. Perhaps this development serves both the cabinetmaker and the user equally well. The cabinetmaker gains a little time while the customer acquires decorative tips at top and bottom of his hinges. These hinges suit architectural cabinetwork particularly well as in effect they are smaller relatives of standard door hinges and allow a conceptual continuity throughout a house. Their applicability to furniture use is less historically justified and as they are built with clearance to allow the pin to be easily withdrawn they are not as precise as their fixed pin equivalents. The voting these days is clearly in favor of loose pin hinges but a user needs to be aware that a hinge without balls or urns is not lacking any vital part.
Swaged & Flatback Hinges
We carry both swaged and flatback hinges in all sizes for both cabinet and architectural applications. Here follows an explanation of these two outwardly similar hinge types.
The traditional English hinge is a flatback design while the traditional American hinge is a swaged style. For all practical purposes there is little to choose between them. The American swaged form is the result of a manufacturing tradition that extends back to the early part of this century. Then, as now, by far the bulk of American hinges were formed of sheet material .The practicalities of forming hinge sections from sheet material generally favored the use of thinner material than might otherwise be desired and in order to make a stronger more wear resistant product the barrel of the hinge was enlarged to create bigger bearing surfaces. Standards that eventually became defined by trade and government agencies naturally reflected the then current state of the technology. So all American hinges to this day, however they are manufactured, still bear the characteristics of an economical mass produced product. Our American made swaged hinges are milled from solid brass extrusions rather than folded from sheet material. This results in a hinge with a more precise fit, a much longer life and far better finish.
The design of our English flatback hinges is also the direct consequence of past manufacturing methods though in their case a century or more older. The first English brass butt hinges were hand fitted and finished sand castings. To compensate for the brittleness of this material the hinges were made as thick as possible within the limits of any particular hinge size. The flat back design allows the thickness of each hinge leaf to be close to half the diameter of the hinge barrel and even though hinges are no longer sand cast the profile of the modern English hinge remains the same as it was 200 years ago. A subtle detail found in our English butt hinges is the tapering of the leaf. Back when these hinges were still cast brass the greatest weakness was where the leaf section meets the hinge barrel. It is along this line that breakage almost invariably occurs. In contrast, the edges of the leaf are under no stress and could just as well be thinner so the hinge makers would taper the leaf away from the barrel.
For any given hinge size the leaf thickness of a flatback hinge will tend to be greater and the barrel diameter smaller than the equivalent swaged hinge. Your choice between these two hinge types should ultimately be based on taste and period. The flatback hinges with their slender elegant barrels should certainly be your choice if you are replicating the flavor of period furniture while the more imposing barrels of the swaged hinges suit heavier late 19th and 20th century styles.