The sine plate is a tool that is used to take measurements of angles for parts. The use of a sine plate is very similar to that of a sine bar; yet the layout and function of these two tools are slightly different. Though a sine plate is used mostly as a precision measurement tool, it can sometimes be used as a clamping device to hold parts in place. Besides the sine bars and sine plates, the other measuring tools that apply the similar mechanism and principle are the sine block and the sine vise. These devices are all used to take the measurement of angles for parts that have particular presentations. There is also sine vise that is especially made to clamp a work piece while taking measurements.

Sine Plate

A sine plate is used to hold work pieces in place at a particular angle in order to guide accurate machining works at specific angles. Since the work pieces are placed and secured on the surface of the sine plate, the sine plate is also called a sine table. The sine plates have a surface plate, a top plate and a column in composition. When a sine plate works, the top plate is tilted with one end raised from the base. The component that raises the top plate is a gauge block or a slip gauge. The gauge is responsible for setting the height and angle of the plate. Once the plate is raised to the desired angle, it can be locked in place.

Sine Bar

A sine bar is comprised of a surface plate and the sine bar itself. There are two cylinders on the two ends of the bar. Just like how a sine plate works, the sine bar can also be raised and tilted by the precision cylinder on one end. The key difference between a sine bar and a sine plate is the way they secure the work piece in place. The work pieces are secured on the top plate of a sine plate while there are holes along the sine bar. The holes are threaded or machined so that stops or clamps can be attached on to the bar. A sine block is highly identical to a sine bar except that a sine block is wider than a sine bar.

Sine Vise

Sine vise is typically considered as a type of sine bar. On a sine vise, there are no holes for the stops or clamps to attach. Instead, the bar is replaced by a vise. The sine vise is essentially a twist of sine bars or sine plates that combines the same working principle with a clamping vise. With a sine vise, the work pieces are secured by the jaws. After the jaws clamp the work pieces in place, the vise will be tilted to the desired angle for the following operations. The use of sine vise is ideal when the work pieces cannot be effectively held by a sine plate or a sine bar.

Working Principle

The working principle of these precision measurement tools is based on the law of trigonometry. When the top plate of a sine plate is raised by the slip gauge, the surface plate, the top plate and the slip gauge together form a triangle. The top plate is the hypotenuse of the triangle, the perpendicular is the slip gauge, and the surface plate is the base. The height of slip gauge is H and the length of the top plate is L. The angle sine theta is H divided by L.

The triangle that is formed by the surface plate, top plate and slip gauge allows the sine equation to be applied to calculate a range of measurements. The length of the top plate or the sine bar is often five inches or ten inches because it makes the calculations more convenient. When the value of hypotenuse is fixed, the only changing factor to the calculation is the perpendicular. Since the working principle is simple, the use of these measurement tools is not only easy, but also efficient and accurate.

IMTS Exhibition includes manufacturers from around the world. Send us a message with your requirements and our IMTS Experts will happily help you with your questions.

Select Category

You can see all Sine Plate categories