The following is excerpted from Chapter 3 of Christopher Schwarz’s “Campaign Furniture.”
For almost 200 years, simple and sturdy pieces of campaign furniture were used by people all over the globe, yet this remarkable furniture style is now almost unknown to most woodworkers and furniture designers.
“Campaign Furniture” seeks to restore this style to its proper place by introducing woodworkers to the simple lines, robust joinery and ingenious hardware that characterize campaign pieces. With more than 400 photos and drawings to explain the foundations of the style, the book provides plans for nine pieces of classic campaign furniture, from the classic stackable chests of drawers to folding Roorkee chairs and collapsible bookcases.
Few things separate a piece of campaign furniture from ordinary furniture as much as the hardware.
In fact, antique dealers (and the clueless) will pretty much call anything that has brass corner guards a “campaign” piece. You see this especially with writing slopes, a common piece of furniture for a couple centuries that every literate citizen used – not just military officers and colonists.
I consider this a minor mistake and gladly overlook it. After all, most of these writing slopes (which some people call lap desks) were built as tough as a campaign piece, using nice woods, hardware and leather. So they were designed to be taken on “campaign,” even if that was just to the park.
What is less forgivable is when an unscrupulous dealer calls screwed-together plywood pieces “campaign furniture” because someone has tacked on some corner guards or rectangular brass pulls. The truth is that the campaign style has had some minor revivals over the years. So you can find “campaign chests” (and end tables, coffee tables and entertainment units) from the 1970s.
So while authentic campaign furniture is something that goes far beyond its hardware, the brasses are a critical part of evaluating a piece. And for a maker, the brasses are one of the major expenses when building a piece. When you shop for hardware, it’s tempting to buy pulls that look OK from 10′, but feel like tin foil in the hand.
This short chapter is designed to introduce you to the different kinds of hardware and the ways they are made – cast, extruded, bent, welded and die-cast. And to teach you a bit about the strategies for installing inset pulls, corner guards and the other inset plates common on campaign pieces.
How Hardware is Made
Like your tools, the brasses for your furniture can be made in many different ways. The process affects how the hardware looks, feels in the hand and costs.
A lot of campaign brasses I’ve studied have been cast. There are several ways to cast metal; the three most common methods for making hardware are sand casting, die-casting and investment casting (and their variants).
While all these casting processes are different in their details, they are the same in their basic idea: There is a mold made in the shape of the hardware and it is filled with molten metal. When the metal cools, the casting is finished and assembled.
All three types of casting have advantages and disadvantages for you, the furniture maker, and I’ll be covering them in some detail here. Most woodworkers are woefully uneducated about the way hardware is made and as a result make bad decisions. As you are about to see, a little education about metal casting can go a long way toward improving the quality of your projects. Let’s start with sand casting.
Many handplane bodies (and woodworking machines) are made using sand casting. It allows a maker to produce castings in an economical way. The downside to sand casting furniture hardware is that the surface finish is never nice enough to use as-is. The manufacturer usually needs to finish the visible surfaces and touch points. This can be labor- or time-intensive.
But what is more important for a furniture maker is that the finishing process can make the parts non-interchangeable, especially if the pieces are finished by hand. The upside is that hand-finished hardware with small variations can be beautiful.
Hardware made this way is called “sand cast” because a sand that is moistened with oil or chemicals is used in the casting process The casting begins with a “pattern,” which was traditionally wood, but is now typically aluminum for pieces of hardware. Then either the pattern or a matchplate or some other representation of the finished object is used to make depressions in two boxes of sand – one is called the cope and the other is called the drag. These two bits of sand are put together and the cavity is filled with molten metal via tubes called “sprues” in casting parlance. Gates are put into the matchplate or simply cut into the sand itself to allow the metal to flow completely through the part and out the other side. This helps the metal completely fill the cavity and helps prevent shrinkage (which is a cause of surface pitting).
After the metal hardens, the sand is removed (and reused) and the resulting metal shape is finished – by grinding, filing, polishing, machining or some combination of these processes. After grinding and/or filing, all cast parts are put into vibratory tumblers filled with a variety of different medias to get the surface finish smooth. The tumbling is the key process that turns a very rough casting into a smooth finished part. Machining typically takes place after tumbling.
Sand casting produces hardware that typically has a substantial feel. Its components are fairly thick. The unfinished faces of the hardware will typically be a bit coarse – like sand. (Proper tumbling eliminates this rough surface.)
These qualities are the nice things about sand-cast objects, but there are some downsides with sand-cast hardware. The level of detail isn’t as good as with other casting methods. So a sand-cast lion’s face will look a bit “blurrier” than one cast by other methods.
Also, the sand-casting process can result in some variance in dimensions. This is not a big deal at all if you install your hardware piece by piece. But if you want to have one router template for all your inset sand-cast pulls, you might want to closely examine the pulls first and see how close in size they are to one another.
Believe it or not, sand casting (the oldest form of casting, by far) can be done at home or even on the beach. Peter Follansbee once showed me ring pulls that he and other researchers at Plimoth Plantation made on the beach. And Thomas Lie-Nielsen fondly recalls how his father – a boatbuilder – would cast the keels of his boats on the beach.
Investment (Lost Wax) Casting
Investment casting is a more complex process than sand casting, but it is suited for small objects and short runs, and results in some fine details that might not require additional finishing.
The process is complex (and can be more expensive than sand casting), but it starts with a pattern that goes through several stages of production involving creating a wax mold of the object that is then covered in a ceramic material.
Investment-cast pieces of hardware have few downsides, other than the fact that they are typically more expensive than a similar sand-cast object. They allow much finer detail than a sand-cast piece, can have a much thinner cross-section and have the presence of a sand-cast piece.
Orion Henderson, the owner of Horton Brasses, says that investment casting can be pretty economical for very small parts. He says the downside to investment casting is that the metal suffers from greater “shrink” – when the metal cools it gets smaller, leaving pitting; the part gets so small that sometimes the part is not usable. The molds need to be oversized to account for this. Because of this shrinkage, Henderson says, investment casting is fine for small parts but not as suitable for big pieces – a bed wrench for tightening bed bolts, for example.
Die-cast objects get a bad rap. And that’s because die-casting has been used with lightweight raw materials to produce lightweight (sometimes featherweight) pieces of furniture hardware. They are inexpensive and look good from across the room. But once you grab the hardware, it can feel insubstantial.
Like all casting processes, die-casting has a mold – in this case a two-part metal mold called a die that is machined with hollow areas. Molten metal is injected under pressure to fill the hollow areas in the die. Then the two pieces of the die are mechanically separated and the finished part is ejected.
Die-casting produces parts that require little or no finishing. The parts are remarkably consistent. You can make many of them in a minute, and the individual units are inexpensive as a result. So why do some people dislike the process?
Like all technology, die-casting isn’t the problem. It’s how it is employed.
You can use copper (or even lead) in die-casting to make a nice and heavy piece of hardware. (In fact, die-casting was invented in the early 19th century to make movable lead type for printing presses.) But in many instances, the manufacturer will use lightweight metals, such as aluminum, tin, zinc or Zamak, an alloy of lightweight metals.
To be honest, these lightweight metals are fine for some pieces of hardware. A drawer knob, for example, can be just fine when it is die-cast. But when you get into pieces of hardware that have movable parts that you grab, such as a drawer pull, the whole thing can feel chintzy.
You can identify die-cast pieces of hardware easily, even if its catalog description doesn’t mention the process. The finished casting is pushed out of the die by ejector pins – movable rods inside the die. These pins leave telltale round marks on the hardware. Look for them on the back of the hardware, and you’ll start to see them everywhere.
When it comes to the corner guards that are prevalent in campaign furniture, many modern manufacturers will use thin brass plate that is bent and sometimes welded at the corners.
This might sound like a cheap shortcut. It indeed is a shortcut compared to cast-brass corner guards, but it can be a good shortcut.
The plate is more consistent in thickness than any piece of sand-cast hardware. So installing it is easier because you can use one depth setting on your router plane or electric router.
The downside to using brass plate is that the corners of the hardware – both the inside corners and outside corners – are rounded because of the bending process. The cast corner guards can have sharp inside and outside corners. It’s a subtle difference, but it is noticeable once you are sensitive to it.
If you do use hardware made from bent plate (and I do), look for welds at the corners when the hardware covers three surfaces, such as when you have a brass guard designed for the top corners of a chest. A quality guard will be bent then welded. Some of the less expensive guards are simply bent with no weld. This looks just weird and wrong to my eye.
Some of the hardware you’ll see in catalogs will indicate it is “extruded.” Extruding hardware parts is analogous to making macaroni or using the Fuzzy Pumper Barbershop with Play-Doh. Metal (cold or hot) is pushed through a die to make a finished shape that is then cut up to finished lengths.
Many quality hinges are made with extrusion. The leaf and barrel are extruded. Then they are cut to length and machined to accept screws. The only downside to extruded hardware is its price.
So why is all this talk about hardware manufacturing important? I think that hardware can make or break a piece of campaign furniture. A zinc die-cast drawer pull on a teak chest is like a nugget ring on a millionaire’s hand.
When I am shopping for hardware for a piece of campaign furniture, I like to purchase a sample pull, hinge or corner guard to inspect the quality before dropping hundreds of dollars on a suite for a chest or trunk.
The samples also help me ensure that the color and finish on the hardware will work. And the color of the brass is another can of worms we need to open.
If you buy your hardware from several sources for one piece of furniture, the chance of them matching in color is tiny. And the last thing I want to do after spending $700 on pulls is to open a chemistry set to strip the hardware pieces and color them.
If you like dabbling in solvents and other noxious fumes, you can easily find information on how to strip the lacquer from your hardware and color it with ammonia fumes. Me, I have enough volatile organic compounds in my life. I’d rather leave that to other people.
That’s why I take one of two strategies when buying hardware: Either I buy all the pieces from one maker to ensure they have a consistent color, or I ask (nicely) if the hardware seller can color the pieces. The better hardware merchants are happy to do this for you. In fact, some will even bring in hardware from other sources and color your entire suite so everything looks the same. It might cost a little more to go this route, but the results are worth it.
One last note about buying hardware and I’ll shut up: I think slotted screws are really the only kind of screw that looks good on a campaign piece. Phillips screws are a 1930s invention that were intended for assembling cars – not fine furniture.
Once you get your hardware in hand, you can build the piece and install the pulls, knobs and corner guards. There are several strategies for creating the recesses for the hardware, ranging from a chisel and a mallet all the way up to templates for the electric router and pattern-cutting bits.