Hand screws are a form of clamp designed to be tightened by hand with a set of screws. They are most commonly used in woodworking, although people in other industries may have use for them as well. Woodworking suppliers and hardware stores often stock hand screws, usually in a variety of sizes so that people can assemble collections which offer several different options. This style of clamp can be very useful to have around the workshop.
The design of the hand screw includes two separate blocks of wood with drilled holes. Screws attached to knobs or handles for convenience are passed through the holes on either end of the block. To use the hand screws, people position the blocks around the object being clamped, and then hand tighten the screws to draw the blocks together and hold them in place. Once the desired level of tightness is obtained, the clamp will hold the object. Hand screws can be used for clamps to hold things while glue sets, and as as clamps to lock objects in place while people work on them.
One reason hand screws are popular among woodworkers is that they do not mar the surface of the objects they clamp. The blocks are broad, distributing pressure rather than concentrating it in a single place, and they are smooth, so they will not leave impressions in the material being clamped. There is also a very high level of control over pressure with hand screws which people can use to avoid common problems such as accidentally splitting wood by clamping it too firmly.
Using hand screws does require a little bit of skill. It is critical that the screws be advanced evenly, or the pressure will become uneven. Uneven pressure can cause the clamped object to slide or slip out of place. It is also important to start with the blocks parallel to each other, because if they are not, it will not be possible to create even pressure.
Like other tools, hand screws work best when people care for them. The wooden blocks are usually made from durable wood which should withstand years of use, but they should still be stored in a cool dry place to prevent warping and splitting. People may also find that it is a good idea to periodically soap and oil the block with products designed for cleaning and oiling wood. The screws are generally rust resistant, but they can still benefit from a light wipe down and oiling occasionally to keep them working smoothly.