Wood Clamps
Description of Woods ability to be worked with
Wood is a remarkable material. It’s widely available, handsome, and immensely diverse. Many of its varieties are easily shaped in a hundred different ways. Wood is fastened to metal, plastic, or other pieces of wood, using nails or screws. However, just as easily clamped and glued
The Strength of Wood and its Glueability
A properly prepared glue joint is as strong as the natural strength in the wood itself. I’ve seen many broken pieces of furniture that snapped and cracked not at a glue joint but as a result of flaws in the wood itself. Not every glue joint is perfect. However, perfect joints can endure for centuries.
Use of Clamps
The first key to a good joint is proper clamping. The clamp—most are devices with pairs of jaws that are drawn together with screw mechanisms—They are used for holding the glued pieces tight and flush until the glue sets. The other key is the glue, and using the right kind in the right way. But first let’s talk about the array of clamps that are available.
Types of Clamps
Clamps are invaluable tools in the workshop. Unlike the vice, another tool that can be used to hold work pieces together. Clamps are easily portable, which makes them most convenient problem solvers at the work-site. Here are a few clamps for which you may well find many applications.
C-Clamps
These multipurpose clamps get their name from their shape. Especially practical for gluing in tight spaces, these clamps have jaws in the shape of the letter C. They have metal shoes at their ends to hold work pieces tightly. They are driven by a screw drive and a T bar that forms a handle on the screw. In general, finger-tightening will provide adequate force. The shoe is mounted on a ball joint, allowing it to sit flush even to slightly angled stock.
C-damps are made of aluminum, iron, or steel, and are designed to clamp metalwork. When used with plastic or wood protective pads or scrap pieces of wood are generally used to protect the material. If don’t use scrap pieces your project will have marks left by the clamp shoes when tightened. Clamps come in a range of sizes, with jaws as small as one inch and as large as twelve inches. Some have deeper throats than others, to accommodate clamping some distance from the edge of the work piece.
Bar Clamps
The bar is the backbone of this clamp, a rectangular length of steel or aluminum. There is a jaw at one end of the bar, and a tail slide that moves up or down its length. The tail slide can be fixed in the desired position at one end of the workpiece that is to be clamped. Depending upon the design of the clamp, this is done using a peg that passes through the bar or by locating the slide at one of the notches in the bar. The adjustable jaw device, which uses a screwdrive, can then be tightened over the workpiece at the other end.
Bar clamps, which are also known as joiner’s clamps, are sold in two- to six-foot models. The steel clamps, in particular, can exert considerable force in clamping. Pipe clamps and bar clamps have strongjaws, and can be used in rough framing to pull a reluctant joist or header into place. More often, they’re used in cabinetwork or to repair doors or windows.
Pipe Clamps
At first glance, the pipe clamp resembles the bar clamp, save that the spine is in the form of a length of pipe. As with the bar clamp, the pipe clamp has a jaw that in most models is fixed on the pipe. A second sliding jaw is positioned anywhere on the length of the pipe. The moving jaw is locked in place with a cam operated by a lever mechanism. Therefore, longer projects are able to be clamped using the pipe clamp. For projects that are longer than the clamp the clamp fittings can be transferred to a longer pipe.
All-wood Hand-Screw Clamps
All-wood hand-screw clamps were used for generations. One great advantage of wooden hand-screw clamps is their ability to apply pressure evenly over a larger area than most clamps because they won’t leave a mar a work piece when tightened.
The wooden screws in the older models travel freely through one jaw and thread into the other. The front and rear screws are the reverse of one another. The newer, steel-screw models have threads at each of the points of connection with the jaws. The thread on each rod reverses at its midpoint, for ease of adjustment. Both wooden and wood-and-steel designs can be loosened or tightened by gripping them with both hands, a handle in each hand, and rotating the clamp. A clockwise rotation tightens the clamp.
For most uses, the clamp should be tightened to fit the workpiece with the jaws roughly parallel. When the mouth of the clamp is snug over the workpiece, turn the rear handle to fully tighten the clamp. When gluing, take care to avoid gluing the wooden jaws to the workpiece.
Over the years, these clamps have been manufactured in a great range of sizes, and today clamps can be purchased with jaws that open up to a maximum of twelve inches or more. Typically, the hardwood jaws are between eight and eighteen inches long and between one and a half and two inches square.
Spring Clamps
These clamps mimic the shape and function of the human hand when you are grasping something between your thumb and forefingers. This clamp enables the craftsman to do be able to work on the piece that would have to normally be held manually by a second person. The clamp’s jaws are usually made of steel so a layer of plastic applied to reduce scarring on soft materials, A spring holds the jaws tightly closed.To release the clamp by squeezing the handles together. Spring clamps are sold in various sizes that open one, two, three, or more inches.
The most common use for this clamp is for holding a cutting jig used to guide a circular saw when cutting large pieces of plywood
Strap Clamp
The Strap Clamp also called web or band clamps are clever devices. The clamp relies on a belt-like length of webbing to tighten joints in a structure. A mechanical device functions as a kind of elaborate buckle, with a ratchet that allows the one-and-a-half-inch-wide belt to be tightened.
Strap Clamps are especially useful in furniture work, tightening frames and cases (even round ones), The seemingly impossible clamping tasks are easily accomplished with the use of this clamp
When using a clamp, make sure you remove any extra glue from the clamp. Excess glue will glue the clamp to the work causing and unprofessional work.
