How do you calculate sine bar?
Sine Bar Set-Up Calculation To calculate the gauge block’s height needed to set-up a sine bar to a specific angle all you have to do is take the SIN of the angle and multiply it by the sine bar length. The length of the sine bar is the distance between the centers of the sine bar gauge pins.
Why is sine bar limited to 45 degrees?
3. Why is a sine bar not suitable for measuring angle above 45? The sine bars become inaccurate as the angle exceeds 45° because the bar(product) is physically clumsy to hold at that position and even a slight error of the sine bar can cause large angular errors.
How the length of sine bar is specified?
The size of a sine bar is specified by its length. The length of the sine bar is the distance between the centres of the rollers. The commonly available sizes are 100 mm, 200 mm, 250 mm and 500 mm.
What is a machinist sine bar?
The sine bar or sine plate is used for accurately setting up work for machining or for inspection. Gage blocks are usually used for establishing the height. Rule for determining the height of the sine bar setting for a given angle: multiply the sine of the angle by the length of the sine bar.
How do you calibrate a sine bar?
This is typically achieved using gage blocks. It’s important to ensure the center to center distance between cylinders, the radius of each cylinder, and the parallelism of the flat surface to the radius centers are all known since the sine bar accuracy relies on the precise measurements of these objects.
Why there are holes in sine bar?
Sine bar consists of a precisely machined corrosion resistant chrome steel. It is essentially hardened and stabilized. The relief holes are drilled into the body of sine bar to reduce the weight, and to facilitate handling.
What angle sine bar gives maximum accurate reading?
between 15° to 45°
Sine bar is more accurate for angles between 15° to 45°, below and above to this limit, angles measured are not much more accurate.
Why rollers are used in sine bar?
Measure the angle of small components; the sine bar is set approximately at an angle to the surface plate by placing a roller of the sine bar on a combination of the appropriate gauge slip. Dial gauges are used to check whether the upper surface of the component is parallel to the surface plate.
What are the limitations of sine bar?
Following are the limitations of sine bar:
- Any unknown projections present in the component will cause errors in the measured angle to be induced.
- For the construction of slip gauges, there is no scientific approach available and it has to be built on trial and error basis and it is a time-consuming process.
For what purpose sine bar is used?
A sine bar is used in conjunction with slip gauge blocks for precise angular measurement. A sine bar is used either to measure an angle very accurately or face locate any work to a given angle offering a high degree of accuracy in measuring angles for milling, grinding and inspection applications.
What is the standard length of a sine bar?
Sine bars or sine plates usually have a length of 5 inches or 10 inches. These standard lengths are commonly used by the tool maker or inspector.
What is the formula for sine bar?
The distance between the two setting rollers of the Sine Bar is given by L. From this we can write θ = sin^-1 (h / L). This is the formula for sine bar for calculating the angle or setting the workpiece to the required angle. This device is called “Sine Bar”.
What is a sine bar used for?
A sine bar is a device used to measure angles in metals. It consists of a hardened ground body with two precision ground cylinders attached at the ends. The distance between the centres of the cylinders is accurately controlled, the top of the bar is parallel to a line through the centres of the two rollers.
What is the use of sine bar and Gage block?
The sine bar or sine plate is used for accurately setting up work for machining or for inspection. Gage blocks are usually used for establishing the height.